US20070154336A1

US20070154336A1 - Fluid transportation device

Info

Publication number: US20070154336A1
Application number: US11/598,077
Authority: US
Inventors: Hajime Miyazaki; Mamoru Miyasaka; Kazuo Kawasumi; Eiji Mochizuki; Susumu Kobayashi; Toshio Mori; Nao Hashimoto
Original assignee: Seiko Epson Corp; Misuzu Industries Corp
Current assignee: Seiko Epson Corp; Misuzu Industries Corp
Priority date: 2005-11-17
Filing date: 2006-11-13
Publication date: 2007-07-05
Also published as: JP2007275548A; JP4355722B2

Abstract

A fluid transportation device includes: an outer case having a sealed space; a tube having elasticity; a fluid transport mechanism having fingers that occlude the tube and a cam that successively presses the plurality of fingers; a driving force transmission mechanism disposed so as to be overlapped with the fluid transport mechanism, and transmitting a driving force to the fluid transport mechanism; a reservoir disposed at a position so as not to overlap the fluid transport mechanism and the driving force transmission mechanism; a port through which the fluid is injected into the reservoir; and an electric power supply supplying electric power to the driving force transmission mechanism. In this fluid transportation device, at least the fluid transport mechanism, the driving force transmission mechanism, and the electric power supply are housed in the sealed space of the outer case.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No. 2005-332450, filed on Nov. 17, 2005, Japanese Patent Application No. 2006-030580, filed on Feb. 8, 2006, Japanese Patent Application No. 2006-070685, filed on Mar. 15, 2006, and Japanese Patent Application No. 2006-304456, filed on Nov. 9, 2006, the contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field
The present invention relates to a fluid transportation device, in which a tube is pressed to make a fluid flow.
Specifically, this invention relates to a structure of a fluid transportation device, in which a driving force transmission mechanism for watch movement is used as a fluid transport mechanism, the fluid transport mechanism and the driving force transmission mechanism are overlapped, these mechanisms and a reservoir are positioned in a planarly shifted configuration, and the mechanisms are sealingly housed inside a casing.
The present invention also relates to a structure of a fluid transportation device that is implanted under the skin of an experimental animal, etc., and feeds a drug solution into the body of the experimental animal, etc.
2. Related Art
Compact fluid transportation devices (pumps) that can be carried close to the human body have been known since before.
Japanese Patent No. 3177742 discloses a fluid transportation device that includes a pump module, having a coupling element, and a motor module.
With this fluid transportation device, the motor module has an output gear mechanism, provided with a power takeoff unit coupled to the coupling element, a step motor that drives the output gear mechanism, a control circuit, and a battery.
The pump module and the motor module can be assembled and disassembled to and from each other.
The coupling element is constituted from a gear, and the power takeoff unit is constituted from a pinion.
Previously, efficacies of drug solutions have been tested and verified using mice, guinea pigs, and other small animals, and various drug solution feeders (fluid transportation devices) that feed a drug solution to a small animal have been proposed for this purpose.
Among these, a drug solution feeder of a type in which a harness is fitted onto a mouse as an experimental animal, a catheter, supported by the harness, is inserted though the skin of the experimental animal, and a drug solution is then fed continuously, has been proposed as disclosed in Japanese Unexamined Utility Model Application, First Publication No. H5-74511.
Meanwhile, a drug solution feeder (fluid transportation device) of a type that is implanted inside a body of an experimental animal has been proposed as described in an animal experiment equipment catalog of Bio Research Center Co., Ltd. (subcutaneously implanted access port for small animals).
With this type of drug solution feeder, a specialized needle is inserted from the exterior of the experimental animal into the drug solution feeder inside the body of the experimental animal, and upon injecting a drug solution via the needle, the drug solution is injected into the body of the experimental animal via a catheter.
In addition to the above, an artificial pancreas device that is implanted inside a human body to supply insulin to a patient is known as has been proposed in Japanese Unexamined Patent Application, First Publication No. 2001-286555.
As disclosed in FIG. 1 of this Patent Application, this artificial pancreas device includes a rechargeable battery as an electric power supply, an insulin reservoir that stores insulin, a micropump that delivers the insulin into an abdominal cavity, etc., and is implanted in a patient.
With this artificial pancreas device, for example, insulin in an amount for one month is supplied to the reservoir via transcutaneous puncture once every month.
Japanese Patent No. 3177742 provides a structure that enables coupling and decoupling of a pump module and a motor module, and this coupling and decoupling operation can be performed by a physician or a nurse.
However, with a structure that enables such operation, it is difficult to ensure waterproofness between the pump module and the motor module, and thus implantation inside a living body is not satisfactory.
The motor module and the pump module are coupled together by engaging the pinion, provided at the motor module side, with the gear, provided at the pump module side.
In assembling by engaging the pinion and the gear in this manner, because the pinion and the gear are normally not matched in phase, the workability is significantly poor.
It is also predicted that the pinion and the gear become flawed easily, and this may obstruct driving in the case of low torque driving using a step motor for a watch.
Also, a reservoir, which contains a drug solution, and a main pump unit are disposed separately and connected by a tube, and when, for example, the main pump unit is implanted inside a living body, the interior and exterior of the living body communicate via the tube, and infection, etc., may occur readily at this communicating portion.
Furthermore, to perform driving upon addition of the drug solution, the reservoir must be exchanged, and this may cause interruption of continuous injection of the drug solution.
With the drug solution feeder of Japanese Unexamined Utility Model Application, First Publication No. H5-74511, because a drug solution feeding unit is disposed at the exterior of the experimental animal, the drug solution feeding unit tends to move away from the experimental animal when the experimental animal moves around and there is thus the danger that the catheter will become removed from the experimental animal.
Also, because the catheter is inserted into the experimental animal, there is a high possibility of the occurrence of inflammation of the skin at the inserted portion, etc.
With the above-described drug solution feeder for the subcutaneously implanted access port for small animals, because a micropump that feeds a drug solution from the drug solution feeder into a body of an experimental animal is not provided, feeding of a drug solution into a body of an experimental animal is basically dependent on the ability to feed the drug solution from the specialized needle at the exterior.
A drug solution therefore cannot be fed continuously and quantitatively to an experimental animal.
With the above-described artificial pancreas device of Japanese Unexamined Patent Application, First Publication No. 2001-286555, the device that feeds insulin is implanted in a body of a patient, and because the catheter is remains inside the abdominal cavity, it can be assumed that the artificial pancreas itself is implanted near the abdominal cavity.
Because this device is thus not required to be as compact and thin as a device of a type that is implanted subcutaneously, it is considered that the device is a comparatively large or thick artificial pancreas.
Also, no specific disclosure is made in relation to how the rechargeable battery, insulin reservoir, micropump, catheter, etc., are positioned inside the artificial pancreas.
Also, the above documents do not provide any considerations in regard to the external shape for reducing, as much as possible, discomfort to an animal when subcutaneously implanting a device into the animal.

SUMMARY

An advantage of some aspects of the invention is to provide a fluid transportation device, in which compactness and thinness are realized and which enables additional injection of a fluid into a reservoir at an arbitrary timing, enables microscopic amounts of the fluid to be made to flow continuously and sustainedly, and is highly safe.
An advantage of some aspects of the invention is to provide a fluid transportation device, which, in use upon subcutaneous implantation in an animal, etc., enables a drug solution (fluid) to be fed continuously and with stability.
An advantage of some aspects of the invention is to provide a fluid transportation device, with which a drug solution (fluid) can be supplied from the exterior to a reservoir reliably.
An advantage of some aspects of the invention is to provide a fluid transportation device having an external shape that reduces, as much as possible, discomfort to an animal, etc., in a process of subcutaneously implanting (and after implanting) the device into the animal, etc.
A first aspect of the invention provides a fluid transportation device, including: an outer case constituted of an upper cover and a lower cover, having a sealed space; a tube having elasticity; a fluid transport mechanism, having a plurality of fingers that occlude the tube and a cam that successively presses the plurality of fingers from an inlet portion to an outlet portion, making a fluid flow continuously by squeezing the tube; a driving force transmission mechanism disposed so as to be overlapped with the fluid transport mechanism, and transmitting a driving force to the fluid transport mechanism; a reservoir disposed at a position so as not to overlap the fluid transport mechanism and the driving force transmission mechanism, being in communication with the inlet portion of the tube, and containing the fluid; a port thought which the fluid is injected into the reservoir; and an electric power supply supplying electric power to the driving force transmission mechanism. In this fluid transportation device, at least the fluid transport mechanism, the driving force transmission mechanism, and the electric power supply are housed in the sealed space of the outer case.
Here, for example, a button-type compact battery, used in a watch, etc., may be employed as the electric power supply.
With this invention, because all components of at least the fluid transport mechanism, the driving force transmission mechanism, the battery, the port, etc., are sealingly housed inside the outer case, water, dust, etc., do not enter inside the outer case and use in a living body, in a fluid, or in an environment with much dust is enabled.
Because the fluid transportation device of the first aspect of the invention does not have a tube or other component that protrudes to the exterior of a living body, when, for example, the device is implanted inside a living body, the device does not cause infection at a portion connecting the interior of the living body to the exterior and can thus be used safely.
Because the fluid transportation device has the port through which a fluid can be injected into the reservoir, even when the device is being driven, additional injection of the fluid at an arbitrary timing is enabled and continuous flow of the fluid can be sustained without having to stop driving to perform additional injection of the fluid.
By positioning the fluid transport mechanism, the driving force transmission mechanism, the battery, the reservoir, and the port in the above-described manner, compactness and thinness can be realized.
It is preferable that, in the fluid transportation device of the first aspect of the invention, the reservoir be housed in the sealed space of the outer case.
With this invention, because the reservoir is also sealingly housed inside the outer case, water, dust, etc., do not enter inside the outer case and components, including the reservoir, can be protected from the external environment.
It is preferable that, in the fluid transportation device of the first aspect of the invention, the reservoir be held at an outer side of the outer case and incline with respect to a surface of the outer case.
With this invention, because the reservoir is mounted onto the outer side of the outer case, even when condensation occurs on a surface of the reservoir, influences on the driving force transmission mechanism and the battery can be avoided, rust formation and circuit problems can be suppressed, and durability can be improved.
Furthermore, because the reservoir is held incliningly on the surface of the outer case, when, for example, the fluid transportation device is implanted under the skin, stretching of the skin by an end portion of the reservoir can be avoided and discomfort after implantation can be alleviated.
It is preferable that the fluid transportation device of the first aspect of the invention, further include: a reservoir frame disposed on the outer side of the outer case. In this fluid transportation device, the reservoir is detachably mounted via the reservoir frame.
With this invention, because the reservoir is detachably mounted via the reservoir frame, the reservoir can be held reliably at a predetermined position of the outer case and workability during exchange, etc., can be improved.
Furthermore, when the fluid transportation device is implanted subcutaneously, a lower side of the reservoir is protected from the living body by the hard reservoir frame, and an upper side of the reservoir, by being made open, is enabled to be deformed readily.
It is preferable that, in the fluid transportation device of the first aspect of the invention, the driving force transmission mechanism include: a step motor; and a watch movement, which in turn includes a wheel train having an hour wheel that protrudes in the direction of the fluid transport mechanism, and the cam be insertingly attached to an axial portion of the hour wheel.
Here, a plurality of gears that transmit the rotation of the step motor to the cam is referred to collectively as the “wheel train.”
Because the driving force transmission mechanism is constituted from a watch movement, the driving force transmission mechanism is made compact and thin, and the fluid transportation device can thereby be made compact and thin.
Employment of a mass-produced watch movement that includes the hour wheel, to which the cam is insertingly attached, contributes to cost reduction.
It is preferable that, in the fluid transportation device of the first aspect of the invention, the port be disposed so as to penetrate through the upper cover.
With this arrangement, because there are no members above the port that obstruct an injection operation of injecting a fluid into the reservoir from the port, the injection operation can be performed readily.
It is preferable that the fluid transportation device of the first aspect of the invention, further include: a fluid flow inlet provided at the reservoir and being in communication with the tube; and a fluid injection inlet, being in communication with the port. In this fluid transportation device, the fluid flow inlet and the fluid injection inlet are disposed at separated positions so that the fluid flows in the interior of the reservoir.
The fluid in the reservoir flows from the fluid injection inlet, in communication with the port, to the fluid flow inlet, in communication with the tube.
Thus, by separatingly disposing the fluid injection inlet at an upstream side and the fluid flow inlet at a downstream side, the occurrence of vortex flow and pulsating flow of the fluid can be suppressed and a stable, continuous flow at a predetermined flow rate can be maintained.
It is preferable that, in the fluid transportation device of the first aspect of the invention, the reservoir be formed of a deformable pouch.
Because the reservoir is housed in the sealed space of the outer case, which is constituted from the upper cover and the lower cover, when the fluid is made to flow and is discharged by the fluid transport mechanism, the pressure inside the reservoir drops.
Thus, by forming the reservoir of a deformable pouch so that the volume of the reservoir decreases in accompaniment with the lowering of the internal pressure, the pressure inside the reservoir can be kept substantially constant.
When the tube is occluded by the fmgers and thereafter released, the fluid flows into the released tube, and stable flow of the fluid can be maintained.
It is preferable that the fluid transportation device of the first aspect of the invention, further include: the planar shape of the outer case, constituted from the upper cover and the lower cover, is elliptical and the outer periphery of the outer case is formed in a smooth, streamlined shape.
By making the fluid transportation device have such an outer shape, the biocompatibility of the outer case to living tissue is improved, and thus, when the fluid transportation device is implanted inside a living body, injury to living tissue by the outer case and discomfort due to implantation can be suppressed.
It is preferable that, in the fluid transportation device of the first aspect of the invention, a fluid outlet end of the tube be extended along the outer peripheral shape of the upper cover.
Though details shall be described below by way of embodiments, the fluid outlet end of the tube is protruded to the exterior of the outer case, and by the outlet end of the tube being extended along the outer periphery that is formed in the smooth, streamlined shape, the biocompatibility of the tube to living tissue is improved, and injury to living tissue by the tube and discomfort due to implantation can be suppressed.
It is preferable that the fluid transportation device of the first aspect of the invention, further include: a fluid injection plug provided on the port and being formed of a material with elasticity. In this fluid transportation device, when a syringe-needle-like injection needle is inserted into the fluid injection plug to inject a fluid into the interior of the reservoir and the injection needle is thereafter extracted, the portion at which the injection needle was inserted becomes sealed by the elasticity of the fluid injection plug itself.
Thus, when the injection needle is inserted into the fluid injection plug and the injection needle is extracted after injection of the fluid into the fluid container, the portion at which the injection needle was inserted is closed by the elastic force of the fluid injection plug itself to prevent outflow of fluid from the port.
Such a port can be realized by a simple structure without a valve, etc., and enables the fluid injection operation to be performed repeatedly.
A second aspect of the invention provides a fluid transportation device used for implantation under skin, the fluid transportation device includes: an outer case having a skin side surface and a rear surface, the skin side surface facing the skin when the fluid transportation device is implanted under the skin; a port disposed at the skin side surface, having an injection opening which is exposed to the exterior of the outer case and enables injection of a fluid from the exterior; a reservoir storing the fluid injected from the port; a fluid conducting portion communicated with the reservoir, to allow the fluid to be conducted; a micropump feeding the fluid to the exterior via the fluid conducting portion; and a battery supplying power to the micropump.
With the above-described arrangement, the fluid transportation device of the second aspect of the invention includes the outer case, the port, the reservoir, the fluid conducting portion, the micropump, and the battery as described above, thereby enabling the realization of a fluid transport system that is complete as a so-called self-contained system.
The fluid transportation device can thus be implanted as it is in a body of an experimental animal, etc., (including a human body, and being used in the same meaning elsewhere in this Specification) and does not require a portion connecting to the exterior of the animal as in the fluid transportation device disclosed in Japanese Patent No. 3177742.
The fluid transportation device of the second aspect of the invention thus does not cause inflammation in an experimental animal, etc.
In addition, because the fluid transportation device of the second aspect of the invention is of a so-called self-contained type, a drug solution or other fluid can be fed by just the fluid transportation device itself, and feeding conditions of the drug solution, etc., can be controlled readily as appropriate by controlling the operation of the micropump, etc.
Moreover, the fluid transportation device of the second aspect of the invention is used for implantation under the skin of an experimental animal, etc., and because the port is disposed to face the skin side of the animal, etc., upon implantation of the fluid transportation device under the skin, injection of a drug solution, etc., into the port is facilitated.
That is, when a need to supply the drug solution, etc., arises, because the port is disposed to face the skin side of the animal, etc., the location of the port can be found readily and the drug solution, etc., can be injected readily into the port.
Cases, in which the abovementioned need to supply the drug solution, etc., arises, include cases where the drug solution, etc., is to be supplied immediately after implantation under the skin of the experimental animal, cases where the drug solution, etc., decreases with the progress of an experiment, etc.
“Drug solution” refers to a drug solution for development of a new medical drug, a nutrient solution for supplying nutrition to a small animal, etc., or other liquid that provides a medical effect.
It is preferable that, in the fluid transportation device of the second aspect of the invention, the reservoir and the micropump be separately disposed each other in plan view, and the port be disposed between the reservoir and the micropump in plan view.
The above arrangement provides the above-described actions and effects.
Furthermore, with this invention, because the reservoir and the micropump are disposed away from each other in plan view and practically do not overlap mutually in plan view, the device as a whole is made thin.
The reservoir is required to store as much drug solution or other fluid as possible, and the micropump is required to feed the drug solution, etc., efficiently and powerfully.
Thus, within the fluid transportation device, these two components are comparatively large in capacity/volume.
Thus, if the reservoir and the micropump are not in a separated positional relationship but overlap with each other in plan view (as viewed from a planar direction), the fluid transportation device as a whole becomes thick in cross-sectional view (in a direction perpendicular to the plan view, that is, in the thickness direction).
When such a fluid transportation device is implanted under a skin of an experimental animal, the skin is pulled unnecessarily or the device applies pressure and inflicts discomfort or injury.
In contrast, with this invention, because the device as a whole is made thin, the device does not readily inflict such discomfort.
Thus, even upon implantation under the skin of an experimental animal, etc., unnecessary pulling of the skin, application of pressure or other form of discomfort to the experimental animal, etc., and inflicting of injury are lessened.
The device can thus be used in a state that is substantially close to being normal for the experimental animal, etc.
Also, because the reservoir and the micropump, in each of which securing of a comparatively large volume/capacity is desired, practically do not overlap in plan view, the respective dimensions in the cross-sectional view direction (thickness dimensions) do not interfere mutually and the greatest possible thickness dimensions can be secured.
The reservoir can thus be made to contain a large amount of a drug solution, etc., and the micropump can be made to feed the drug solution, etc., efficiently and powerfully.
Moreover, because the port is disposed between the reservoir and the micropump in the abovementioned plan view, the thinness of the device as a whole is not compromised.
Furthermore, as described above, the port is arranged to be inserted from the exterior by a syringe-needle-like liquid injector for supplying a drug solution, etc., and thus, an external force is applied in the inserting process, an external force in the opposite direction is applied in a process of extracting the liquid injector, and pressure is thus applied to the fluid transportation device as a whole in each of these processes.
With this invention, because the port is disposed between the reservoir and the micropump, which have large surface areas, the location of the liquid injection port is substantially near the center of the fluid transportation device as a whole in plan view.
Thus, even when the pressure in the process of inserting the syringe-needle-like liquid injector into the port or the pressure in the extraction process is applied, the pressure is received by the fluid transportation device as a whole and the likelihood of the fluid transportation device becoming tilted as a whole is reduced.
The operation of inserting in the liquid injector, the operation of extracting the liquid injector, and the liquid injecting operation can thus be performed smoothly.
Also, because the device as a whole does not become tilted, a localized pressure is not applied to an experimental animal, etc., and thus a localized pain is not inflicted.
The burden on the experimental animal, etc., can thus be alleviated, and an experiment, etc., can be continued satisfactorily.
It is preferable that, in the fluid transportation device of the second aspect of the invention, the port have a protrusion formed to protrude from the outer case, and the injection opening be formed in the protrusion.
The above arrangement provides the above-described actions and effects.
Furthermore, with this invention, because the port has the protrusion, which is formed to protrude from the outer case, the following unique actions and effects are provided.
That is, even when the fluid transportation device is implanted under the skin of an experimental animal, etc., the location of the port can be recognized readily from the exterior.
That is, with this invention, because the port is provided with the protrusion as described above and this protrusion protrudes from the outer case, the epidermis of the experimental animal, etc., bulges locally.
In other words, because the fluid transportation device is implanted in the unique location of under the skin of the experimental animal, that is, because the skin (epidermis) is comparatively thin and the device is implanted underneath it, the epidermis readily bulges due to the protrusion.
An experimenter, etc., (including any party attempting to inject a drug solution or other fluid and being used in the same meaning elsewhere in this Specification) can thus readily recognize the location of the port.
The experimenter, etc., can thus readily insert a liquid injector into the center of the bulged portion of the epidermis and supply a drug solution, etc., into the reservoir.
It is preferable that, in the fluid transportation device of the second aspect of the invention, the battery be disposed so as to be overlapped with the reservoir in plan view and be disposed opposite the port across the reservoir in cross-sectional view. With the above arrangement, the battery is disposed so as to overlap with the reservoir in plan view and is disposed opposite the port across the reservoir in cross-sectional view.
Thus, in comparison to a case where the reservoir and the battery, each of which requires a large area in plan view, are disposed away from each other in plan view, the area in plan view is made small and a compact drug solution feeder is provided.
Also, because the port is disposed close to the reservoir in the cross-sectional view direction (thickness direction), a flow path, by which a drug solution, etc., is fed from the port to the reservoir, is shortened and the drug solution, etc., is fed to the reservoir more reliably.
Also, because the flow path is shortened as described above, saving of space can be realized in the fluid transportation device.
It is preferable that, in the fluid transportation device of the second aspect of the invention, the port be disposed at a position so as not to overlap the battery in plan view.
With the above arrangement, because the port is disposed at a position so as not to overlap the battery in plan view, a bottom portion of the port can be formed without the port being obstructed by the comparatively thick battery in the cross-sectional view direction.
A conducting path from the port to the reservoir can thus be disposed at an optimum height.
Also, because a deep guiding opening can be secured for the inserting of a liquid injector into the port from the exterior, the liquid injector that is inserted in is supported by the guiding opening and the operation of supplying a drug solution, etc., is stabilized.
In addition, the thickness dimension in the cross-sectional view direction of the battery can be made large and thus a battery with a large capacity as mentioned above can be employed.
It is preferable that the fluid transportation device of the second aspect of the invention further include: an IC controlling operations of the micropump; a circuit substrate on which the IC is packaged; and a signal supplying port disposed so as to be exposed from the outer case to enable a control program for controlling the operations of the micropump to be supplied to the IC.
With the above arrangement, firstly, control of the operation of the micropump by the IC is realized.
This IC may be configured as a logic circuit or as a microcomputer.
Appropriate control, especially of operations of a rotation drive unit of the micropump is thus enabled.
Setting of a drive starting time and a drive ending time of the fluid transportation device is thus facilitated, and because appropriate control of a feeding amount of a drug solution, etc., during an animal experiment, etc., is enabled, and the animal experiment, etc., can be carried out effectively.
Furthermore, with the above arrangement, because the signal supplying port is provided and is disposed so as to be exposed from the outer case, drive conditions of the micropump can be set at any time after completion of assembly of the fluid transportation device.
The driving program can thus be stored before implanting the fluid transportation device in an experimental animal, etc.
Also, even during an animal experiment, etc., the program can be changed and input according to experimental conditions, etc., via a signal line connected to the signal supplying port and led outside the body of the experimental animal, etc.
It is preferable that the fluid transportation device of the second aspect of the invention further include: an attachment portion formed on the outer case in order to attach to a subject.
With the above arrangement, by passing a thread through the attachment portion, entwining the thread by winding, etc., and sewing the thread onto the animal, etc., the fluid transportation device can be attached to the animal, etc., readily.
Because the attachment portion is disposed at a height such as that illustrated (disposed away from a rear surface of the outer case and toward a skin side surface), in fixing the fluid transportation device onto the experimental animal, etc., by sewing with thread, the sewn portion of the experimental animal, etc., can be brought close to the plan view position of the attachment portion, thereby enabling the fluid transportation device to be attached upon drawing it close to the portion immediately below it and thus be attached in a non-suspended manner.
A third aspect of the invention provides a drug solution feeder (fluid transportation device) to be implanted under the skin of an animal, etc., the drug solution feeder includes: an outer case; a liquid injection port (port), having an injection opening, which is exposed to the exterior of the outer case and enables injection of a drug solution (fluid) from the exterior; a reservoir, storing the drug solution injected from the liquid injection port; a drug solution conducting portion, being in communication with the reservoir and conducting the drug solution; a micropump, feeding the drug solution to the exterior via the drug solution conducting portion; and a battery, supplying electrical power to the micropump, wherein the liquid injection port is disposed so as to face the skin side of the animal when the drug solution feeder is implanted under the skin, and the reservoir, the micropump, and the battery are disposed at mutually separated positions in plan view.
The above arrangement provides the above-described actions and effects.
Furthermore, with this invention, because the reservoir, the micropump, and the battery are disposed at mutually separated positions in plan view and practically do not overlap mutually in plan view, the device as a whole is made thin.
Because the reservoir is required to store as much drug solution as possible, the micropump is required to feed the drug solution efficiently and powerfully, and a large battery capacity is required to be secured at the battery to drive the micropump powerfully or sustain a long drive time, each of these components takes up a comparatively large capacity/volume in the drug solution feeder.
Thus, if at least any combination of the reservoir, micropump, and battery is an overlapping combination in plan view, the drug solution feeder becomes thick as a whole.
When such a fluid transportation device is implanted under the skin of an experimental animal, the device pulls the skin unnecessarily, applies pressure, or inflicts injury.
In contrast, with this invention, because the device as a whole is made thin, the device does not pull the skin unnecessarily, apply pressure, or inflict injury, is unlikely to inflict discomfort on the experimental animal, etc., and can thus be used in a state that is substantially close to being normal for the experimental animal, etc.
In addition, because the reservoir, the micropump, and the battery, in each of which a comparatively large capacity is desirably secured, practically do not overlap in plan view, the respective dimensions in the cross-sectional view direction (thickness dimensions) do not interfere mutually and the greatest possible thickness dimensions can thus be secured respectively.
The reservoir can thus be made to contain a large amount of a drug solution, the micropump can be made to feed the drug solution efficiently and powerfully, and the battery can be made to drive the micropump powerfully or sustain a long driving time.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the liquid injection port (port) be disposed at substantially the center in a narrow width direction in which the drug solution feeder is narrow in plan view.
With this arrangement, because the liquid injection port is disposed at substantially the center in the narrow width direction in which the drug solution feeder is narrow in plan view, the drug solution feeder is prevented from tilting in the narrow width direction when a liquid injector is inserted into the liquid injection port from the exterior or when the liquid injector is extracted.
Thus, as mentioned above, even when the pressure in the process of inserting the liquid injector into the liquid injection port or the pressure in the process of extracting the liquid injector is applied, the drug solution feeder receives the pressure as a whole and the drug solution feeder is thus less likely to become tilted as a whole.
The liquid injector can thus be inserted and extracted satisfactorily and a smooth liquid injection operation can be performed.
Also, because the device as a whole does not become tilted, a localized pressure is not applied to an experimental animal, etc., and thus a localized pain is not inflicted.
The burden on the experimental animal, etc., can thus be alleviated, and the experiment can be continued satisfactorily.
When the liquid injection port is disposed so as to satisfy both the condition of being disposed at substantially the center in the narrow width direction in which the drug solution feeder is narrow in plan view and the condition of being disposed between the reservoir and the micropump in plan view as in the above-described invention, the above-described actions and effects are amplified further.
The narrow width direction in which the drug solution feeder is narrow in plan view refers to the direction of the smaller, that is, the narrower width dimension of the drug solution feeder in plan view.
From another perspective, the narrow width direction refers to the direction that is substantially orthogonal in plan view to a straight line joining a central portion or the center of gravity of the reservoir and a central portion or the center of gravity of the micropump.
Thus, when the plan view shape of the drug solution feeder is a planar shape, in which a width dimension in a wide width direction (longitudinal direction) and a width dimension in a narrow width direction (lateral direction) exist, for example, a substantially rectangular shape, an oval shape, or an elliptical shape, etc., the direction of the straight line joining the central portion or the center of gravity of the reservoir and the central portion or the center of gravity of the micropump in plan view is generally the longitudinal direction.
The direction that is substantially orthogonal to this longitudinal direction is the narrow width direction (lateral direction).
In a case where the plan view shape of the drug solution feeder is substantially circular or is an irregular shape, with which the longitudinal direction and the narrow width direction (lateral direction) cannot be discerned, the abovementioned narrow width direction refers to the direction that is substantially orthogonal in plan view to a straight line joining the central portion or the center of gravity of the reservoir and the central portion or the center of gravity of the micropump as mentioned above.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the liquid injection port (port) have a liquid injector insertable member, disposed at an inner side of the injection opening and formed of an elastic material through which the liquid injector can be inserted, and a drug solution feeding portion, from which the drug solution injected from the liquid injector inserted through the liquid injector insertable member is fed to the reservoir.
With the above arrangement, because the liquid injection port has the liquid injector insertable member, which is disposed at the inner side of the injection opening and is formed of an elastic material through which the liquid injector can be inserted, and the liquid injector insertable member serves as a plug in a state in which the drug solution feeder is implanted under the skin of an experimental animal, body fluids of the animal and other liquids and gases are prevented from entering into the interior of the drug solution feeder.
Contamination of the drug solution by body fluid, gases, etc., can thus be prevented.
Also, because the liquid injector insertable member is formed of an elastic material, the liquid injector can be inserted into the liquid injector insertable member from the exterior for liquid injection.
The drug solution is thereby supplied from the liquid injection port to the reservoir.
As described above, by the liquid injector insertable member being formed of an elastic material, contamination of the drug solution is prevented, and since inserting through of the liquid injector is enabled, replenishment of the drug solution is enabled.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the reservoir have a drug solution injection portion, in communication with the liquid injection port (port), at a side wall at one end, a drug solution discharge portion, in communication with the drug solution conducting portion (fluid conducting portion), at a side wall at the other end, and a drug solution storage portion, formed intermediate to the drug solution injection portion and the drug solution discharge portion.
With the above arrangement, because the reservoir has the drug solution injection portion and the drug solution discharge portion disposed at respective ends of its side wall (a wall in a transverse direction that is not an upper wall or a lower wall in an up/down direction) and not in a thickness direction (cross-sectional view direction, height direction), the reservoir is not made as thick as when the drug solution injection portion and the drug solution discharge portion are provided so as to protrude in the thickness direction.
The drug solution feeder is thus made thin.
Also, in the reservoir, the drug solution is injected from the drug solution injection portion, disposed at the one end and in communication with the liquid injection port, and the drug solution is discharged from the drug solution discharge portion, disposed at the other end and in communication with the drug solution conducting portion.
Because the drug solution injected from the drug solution injection portion is stored in the intermediate drug solution storage portion and then discharged from the drug solution discharge portion, the flow of the drug solution is made continuous, air inside the reservoir is vented readily, and the drug solution flows smoothly without stagnating.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the drug solution conducting portion (fluid conducting portion) be constituted from a tube with elasticity.
With the above arrangement, because the drug solution conducting portion is constituted from a tube with elasticity, the drug solution flow path subsequent to the reservoir can be moved in position and deformed to some degree in shape.
Also, even when there are some dimensional errors in the respective members inside the drug solution feeder, because the elastic tube has elasticity, the position and shape thereof can be corrected readily.
Thus, even if there is variation in dimensions in related members, a good drug solution flow path can be secured.
Furthermore, because the flow path is a tube, the cross-section of the flow path can be made circular, and because a cross-section of high efficiency is obtained in this case, a large amount of the drug solution can be efficiently fed.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the micropump have a rotation drive unit, a cam unit, which is rotated by the rotation drive unit, and a plurality of pressing pins, which are made to press the tube successively in radial directions by the cam unit, and the drug solution is discharged to the exterior by the pressing pins pressing the tube successively.
With the above arrangement, in the micropump, the pressing pins are made to press the tube successively by the cam unit that is rotated by the rotation drive unit.
The tube can thus be pressed by a mechanical driving force of the rotation drive unit, the cam unit, and the pressing pins.
The operation is thus reliable and because a comparatively strong force can be obtained, the drug solution inside the tube can be fed out reliably and powerfully.
Also, because the pressing pins press the tube in radial directions with respect to the center of rotation of the cam unit, the operation of the pressing pins is stable and the tube can be pressed with stability.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the tube have a reservoir connecting portion, in communication with the reservoir, at one end, a drug solution discharge portion, from which the drug solution is discharged to the exterior, at the other end, and an arcuate tube portion, formed intermediate to the reservoir connecting portion and the drug solution discharge portion and disposed at an outer peripheral side with respect to the cam unit and the pressing pins in plan view.
With the above arrangement, because the tube is formed as an arcuate tube portion intermediate to the reservoir connecting portion and the drug solution discharge portion, and this arcuate tube portion constitutes a portion of the micropump, the tube serves both the role of the drug solution conducting portion and the micropump, thereby improving the efficiency.
Moreover, because the tube is formed to be arcuate at this portion, a required length of the arcuate tube portion is secured and a required plurality of pressing pins are disposed.
Moreover, because the cam unit and the pressing pins are disposed at the center side of the arc of the arcuate tube portion, the arc center region can be used effectively and saving of space can be realized with the micropump.
Also, even when the pressing pins protrude and press the tube, the tube can return the pressing pins to the original positions by its elasticity, and in this case, a returning spring member is made unnecessary and the number of parts can be reduced.
When the pressing pins return, the tube returns to its original cross-sectional shape due to its elasticity, thus providing the effect of securing of the flow path diameter.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the battery be overlapped with the rotation drive unit of the micropump in plan view and be disposed opposite the tube across the rotation driving unit in cross-sectional view.
With the above arrangement, the battery has no direct, mechanical relationship with the tube.
Though the battery is disposed near the rotation drive unit of the micropump in plan view, because it is positioned opposite the tube in cross-sectional view, the battery does not obstruct the micropump arrangement constituted of the tube and the rotation drive unit.
The structure of the tube and the rotation drive unit can thus be configured optimally.
It is preferable that, in the drug solution feeder of the third aspect of the invention, the upper cover of the outer case be formed of a transparent material, and at least the reservoir, the micropump, and the tube can be visually recognized from the upper cover.
With the above arrangement, because the upper cover is formed of a transparent material and at least the reservoir, the micropump, and the tube can be visually recognized from the upper cover, an assembly or operation anomaly of the reservoir, the micropump, or the tube can be discovered from the exterior even after assembly of the drug solution feeder.
When an abovementioned anomaly is found, a remedy can be implemented before implantation in an animal, etc.
It is preferable that, in the fluid transportation device of these aspects of the invention, the outer case have inclined surfaces at least at a portion of outer walls extending from the skin side surface to the rear surface.
With the above arrangement, by inclined surfaces being formed on outer walls of the outer case, the biocompatibility of the outer case with respect to living tissue is improved at the portions at which the inclined surfaces are formed, thus enabling injury to the living tissue and discomfort due to implantation to be suppressed when the fluid transportation device is implanted in a living body.
It is preferable that, in the fluid transportation device of these aspects of the invention, the outer case have vertical hold surfaces on outer walls extending from the skin side surface to the rear surface.
With this arrangement, by holding the vertical hold surfaces via the skin after implantation of the fluid transportation device under the skin, the fluid transportation device can be fixed readily, and workability in a case where the device needs to be fixed during injection of a fluid, etc., can be improved.
It is preferable that, in the fluid transportation device of these aspects of the invention, the outer case include: a first-narrow-side outer wall formed along a narrow-width direction at a first end of a wide-width direction; and a second-narrow-side outer wall formed along the narrow-width direction at a second end of the wide-width direction, and the inclined surfaces be formed incliningly so that the first-narrow-side outer wall and the second-narrow-side outer wall converge from the rear surface toward the skin side surface of the outer case.
With the above arrangement, when, in a case where the inclined surfaces are formed, the drug solution feeder is implanted under the skin of an animal, the skin of the animal is pulled according to the volume and height of the drug solution feeder, and in the worst case, the skin is injured.
Because by forming the inclined surfaces in a manner such that the pull is lessened as much as possible and a localized shear force is not applied to the skin, the width of the side closer to the skin is formed narrowly in particular, and the above-described infliction of injury on the skin can be prevented as much as possible.
The angles of inclination of the inclined surfaces are in a range of 5 degrees to 60 degrees and preferably in a range of 15 degrees to 30 degrees.
The angles of inclination of the inclined surfaces may be the same or may differ respectively.
It is preferable that, in the fluid transportation device of these aspects of the invention, the outer case include: a first-wide-side outer wall formed along a wide-width direction at a first end of a narrow-width direction; and a second-wide-side outer wall formed along the wide-width direction at a second end of the narrow-width direction, and the inclined surfaces be formed incliningly so that the first-wide-side outer wall and the second-wide-side outer wall converge from the rear surface toward the skin side surface of the outer case.
With the above arrangement, by the inclined surfaces being formed in the above-described manner on the outer case, when the fluid transportation device is implanted in a body of an animal, etc., the pulling of the skin of the animal, etc., according to the volume and the height of the fluid transportation device is lessened as much as possible in the narrow width direction as well, and because the width of the side closer to the skin is formed narrowly in particular, the above-described infliction of injury on the skin can be prevented as much as possible.
It is preferable that, in the fluid transportation device of these aspects of the invention, the outer case have at least one of either the skin side surface being formed on a protruding surface along the wide width direction or the rear surface of the skin side surface being formed on a recessed surface along the wide width direction.
With the above arrangement, by the skin side surface being formed on the protruding shape or the rear surface being formed on the recessed shape, the outer case is formed to have an upper surface shape or a lower surface shape that becomes substantially aligned with a subcutaneous shape of an animal, etc., when the fluid transportation device is implanted inside a body of the animal, etc., and thus compatibility to the skin, etc., is improved and inflicting of an excessive pull or injury on the animal, etc., can be prevented.
Here, if the skin side surface is formed in the protruding shape and the rear surface is formed in the recessed shape at the same time, the device is aligned readily along a shape of an inner surface of the skin, the subcutaneous shape, etc., of the animal, etc., that contact each skin side surface or each rear surface of the fluid transportation device, and the above-described actions and effects can thus be exhibited more effectively.
It is preferable that, in the fluid transportation device of these aspects of the invention, the outer case have at least one of either the skin side surface being formed on a protruding surface along the narrow width direction or the rear surface of the skin side surface being formed on a recessed surface along the narrow width direction.
With above arrangement, by the outer case being formed to have the protruding surface or the recessed surface or both the protruding surface and the recessed surface as described above, the outer case is formed to have the skin side surface shape or the rear surface shape that becomes substantially aligned with the subcutaneous shape of the animal, etc., even in the narrow width direction when the fluid transportation device is implanted into a body of the animal, etc., as described above and thus compatibility to the skin, etc., is improved and inflicting of an excessive pull or injury on the animal, etc., can be prevented.
As described above, by this invention, a fluid transportation device that can supply a drug solution or other fluid with stability and alleviate the burden placed on an animal, etc., can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a basic arrangement of a fluid transportation device according to a first embodiment of this invention.
FIG. 2 is a plan view of the basic arrangement of the fluid transportation device according to the first embodiment of this invention.
FIG. 3 is a plan view of a watch movement that is employed as a driving force transmission mechanism in the first embodiment of this invention.
FIG. 4 is a cross-sectional view of sectional structures of a wheel train of the driving force transmission mechanism and a fluid transport mechanism in the first embodiment of this invention.
FIG. 5 is a cross-sectional view of a structure related to injection and outflow of a fluid in the first embodiment of this invention.
FIG. 6 is a plan view illustrating actions of the fluid transportation device according to the first embodiment of this invention.
FIG. 7 is a plan view of an arrangement of a fluid transportation device according to a second embodiment of this invention.
FIGS. 8A and 8B are side views of the fluid transportation device according to the second embodiment of this invention, with FIG. 8A being a narrow width side view as viewed from a narrow width side and FIG. 8B being a wide width side view as viewed from a wide width side.
FIGS. 9A to 9C show a reservoir frane in the second embodiment of this invention, with FIG. 9A being a plan view, FIG. 9B being a front view, and FIG. 9C being a side view.
FIGS. 10A to 10D are external views of an outer appearance of a drug solution feeder according to a third embodiment of this invention, with FIG. 10A being a lower side view as viewed from a lower side surface of the drug solution feeder, FIG. 10B being an upper side view as viewed from an upper side surface of the same, FIG. 10C being a right side view as viewed from the right side in FIG. 10A, and FIG. 10D being a left side view as viewed from the left side in FIG. 10A.
FIG. 11 is an enlarged view of a right side portion in FIG. 10A of the drug solution feeder according to the third embodiment of this invention.
FIG. 12 is a plan view of the drug solution feeder according to the third embodiment of this invention as viewed from the upper side of the paper surface of FIG. 10A.
FIG. 13 is a cross-sectional view of principal portions of the drug solution feeder according to the third embodiment of this invention taken along positions A1-A1 in FIG. 12.
FIG. 14 is a cross-sectional view of principal portions of the drug solution feeder according to the third embodiment of this invention taken along positions B-B in FIG. 12.
FIG. 15 is a cross-sectional view of principal portions of a micropump unit of the drug solution feeder according to the third embodiment of this invention shown in FIG. 12.
FIG. 16 is an enlarged cross-sectional view of a liquid injection port of the drug solution feeder according to the third embodiment of this invention.
FIG. 17 is a plan view of a drug solution feeder according to a fourth embodiment of this invention.
FIG. 18 is a cross-sectional view of principal portions of the drug solution feeder according to the fourth embodiment of this invention taken along positions C-C in FIG. 17.
FIG. 19 is a plan view of principal portions of a drug solution feeder according to a fifth embodiment of this invention.
FIGS. 20A to 20D are external views of an outer appearance of a drug solution feeder according to a sixth embodiment of this invention, with FIG. 20A being a lower side view as viewed from a lower side surface of the drug solution feeder, FIG. 20B being an upper side view as viewed from an upper side surface of the same, FIG. 20C being a right side view as viewed from the right side in FIG. 20A, and FIG. 20D being a left side view as viewed from the left side in FIG. 20A.
FIG. 21 is an enlarged view of a right side portion in FIG. 20A of the drug solution feeder according to the sixth embodiment of this invention.
FIG. 22 is a plan view of the drug solution feeder according to the sixth embodiment of this invention as viewed from the upper side of the paper surface of FIG. 20A.
FIG. 23 is a cross-sectional view of principal portions of the drug solution feeder according to the sixth embodiment of this invention taken along positions A2-A2 in FIG. 22.
FIG. 24 is a cross-sectional view of principal portions of the drug solution feeder according to the sixth embodiment of this invention taken along positions B1-B1 in FIG. 22.
FIG. 25 is a cross-sectional view of principal portions of a micropump unit of the drug solution feeder according to the sixth embodiment of this invention shown in FIG. 22.
FIG. 26 is an enlarged cross-sectional view of a liquid injection port of the drug solution feeder according to the sixth embodiment of this invention.
FIG. 27 is a plan view of a drug solution feeder according to a seventh embodiment of this invention.
FIG. 28 is a principal cross-sectional view of the drug solution feeder according to the seventh embodiment of this invention taken along positions C1-C1 of FIG. 27.
FIG. 29 is a plan view of principal portions of a drug solution feeder according to an eighth embodiment of this invention.
FIG. 30 is a cross-sectional view of principal portions of a drug solution feeder according to a ninth embodiment of this invention.
FIG. 31 is a cross-sectional view of principal portions of a drug solution feeder according to a tenth embodiment of this invention.
FIGS. 32A to 32D are external views of an outer appearance of a drug solution feeder according to an eleventh embodiment of this invention, with FIG. 32A being a lower side view as viewed from a lower side surface of the drug solution feeder, FIG. 32B being an upper side view as viewed from an upper side surface of the same, FIG. 32C being a right side view as viewed from the right side in FIG. 32A, and FIG. 32D being a left side view as viewed from the left side in FIG. 32A.
FIG. 33 is a cross-sectional view of principal portions of a Modification Example 1 of a liquid injection port unit in this invention.
FIG. 34 is a cross-sectional view of principal portions of a Modification Example 2 of a liquid injection port unit in this invention.
FIG. 35 is a cross-sectional view of principal portions of a Modification Example 3 of a liquid injection port unit in this invention.
FIG. 36 is a cross-sectional view of principal portions of a Modification Example 7 of a vicinity of a reservoir unit in this invention.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Embodiments of this invention shall now be described based on the drawings.

First Embodiment

FIGS. 1 to 6 show a fluid transportation device according to a first embodiment of this invention.
FIG. 1 shows an arrangement in a thickness direction, FIG. 2 shows the arrangement in a plan view direction, FIG. 3 is a plan view of a watch movement that is employed as a driving force transmission mechanism, FIG. 4 is a cross-sectional view of portions of the driving force transmission mechanism and a fluid transport mechanism, FIG. 5 is a cross-sectional view of a structure related to injection and outflow of a fluid, and FIG. 6 is a plan view of the fluid transport mechanism.
With the present embodiment, a fluid transportation device that is implanted in a living body of a human being, animal, etc., and uses a drug solution as a fluid shall be described as an example.
Gel-like fluids and gases are included in the definition of “fluid.”
FIGS. 1 and 2 are respectively a cross-sectional view and a plan view of the basic arrangement of a fluid transportation device 1 according to the first embodiment of this invention.
As shown in FIGS. 1 and 2, the fluid transportation device 1 according to this embodiment includes a driving force transmission mechanism 3, a fluid transport mechanism 2, a reservoir 60, and a bulb 80 (referred to hereinafter as the “bulb” in regard to the first embodiment).
Here, the fluid transport mechanism 2 is disposed on an upper surface of the driving force transmission mechanism 3.
The reservoir 60 is disposed at a position at which it does not overlap in plan view with the driving force transmission mechanism 3 and the fluid transport mechanism 2.
The bulb 80 that functions as a port is disposed in a planar space between the driving force transmission mechanism 3 and the reservoir 60.
Furthermore, at a rear surface side (surface at the side opposite the fluid transport mechanism 2) of the driving force transmission mechanism 3 is disposed a circuit substrate 5, on which an unillustrated control circuit for drive control of the driving force transmission mechanism 3 is mounted.
A battery 4, which serves as a power supply, is disposed under the reservoir 60.
With the exception of an outlet portion 53 of a tube 50, the fluid transport mechanism 2, the driving force transmission mechanism 3, the reservoir 60, the bulb 80, the battery 4, and the circuit substrate 5 are housed inside a sealed space of an outer case formed by an upper cover 13 and a lower cover 16.
The driving force transmission mechanism 3 employs a watch movement and makes use ofjust a step motor and a wheel train of a compact movement with a barrel-like outer planar shape.
A detailed structure of the driving force transmission mechanism 3 shall be provided later with reference to FIGS. 3 and 4.
An hour wheel at a final stage of the wheel train, disposed at the center of the driving force transmission mechanism 3, is a cam drive wheel 76.
A cylindrical axial portion 76 a of the cam drive wheel 76 is protruded in the direction of the fluid transport mechanism 2.
Cams are fitted onto this axial portion 76 a (see FIG. 2).
The cams are a first cam 20, which is axially fixed to the axial portion 76 a, and a second cam 30, which is axially supported by the axial portion 76 a.
In regard to the second cam 30, by the rotation of the first cam 20, the first cam 20 and the second cam 30 function as if these were a single cam.
The fluid transport mechanism 2 includes the first cam 20, the second cam 30, the tube 50, and seven fingers 40 to 46.
The fingers 40 to 46 are interposed between the tube 50 and the first cam 20 and between the tube 50 and the second cam 30.
The tube 50 has elasticity and, in the present embodiment, is formed of a silicone-based rubber with biocompatibility.
The tube 50 is fitted in a tube guide groove 121 of a tube frame 12, which is a frame of the fluid transport mechanism 2.
The tube guide groove 121 has tube guide walls 122 disposed concentrically about a rotation center P of the cam drive wheel 76.
The fingers 40 to 46 extend radially from the rotation center P at equal intervals and are interposed between the tube 50 and the first cam 20 and the second cam 30.
Each of the fingers 40 to 46 is fitted in a finger guide groove 126 (see FIG. 4), formed in the tube frame 12.
The fingers 40 to 46 are fitted in a manner enabling movement in axial directions inside the finger guide grooves 126 and are pressed by the first cam 20 and the second cam 30 to occlude the tube 50.
Actions of the fluid transport mechanism 2 shall be described later with reference to FIG. 4 and 6.
One end of the tube 50 is the outlet portion 53, from which the drug solution flows out and which extends to the exterior of the fluid transportation device 1.
The other end of the tube 50 is a fluid inlet portion 52, which is in communication with the reservoir 60, and communicates with the reservoir 60 via a connecting pipe 55.
The reservoir 60 is formed of a thin pouch that can swell when filled with the drug solution and become reduced in volume when the drug solution flows out.
The reservoir 60 has a substantially semicircular planar shape, and one end of a portion corresponding to a chord of the substantially semicircular shape is a fluid discharge outlet 63, which is connected to the connecting pipe 55.
The other end is a fluid injection inlet 62, which is connected to an injection pipe 83 that is protruded from the bulb 80.
A drug solution flow path is thus formed of the bulb 80, the reservoir 60, and the tube 50.
The above-described driving force transmission mechanism 3 is held by a movement frame 15.
The fluid transport mechanism 2 is held by the tube frame 12.
The reservoir 60 is held in a space formed by the tube frame 12 and the movement frame 15.
The tube frame 12 and the movement frame 15 are clamped by the upper cover 13 and the lower cover 16.
Fixed shafts 95 are fixed to the movement frame 15.
Opposite ends of the fixed shafts 95 penetrate through the tube frame 12, the upper cover 13, and the lower cover 16.
Fixing screws 90 and 91 are screwed onto the opposite ends of the fixed shafts 95 to fix the tube frame 12, the movement frame 15, the upper cover 13, and the lower cover 16 in close contact.
A planar configuration of the fixing screws 90 (95) is shown in FIG. 2.
The outlet portion 53 is fixed by an adhesive, etc., to a location near an outer periphery of the tube frame 12.
The connecting pipe 55 is also fixed by an adhesive, etc., to the tube frame 12.
The outlet portion 53 and the connecting pipe 55 form a hermetically sealed structure between the tube frame 12 and the upper cover 13 that prevents the entry of body fluids, etc., into the interior from opposite ends of the tube 50.
On the circuit substrate 5 are packaged a crystal oscillator (not shown) that serves as a timing element, an IC 6 that serves as a control circuit, and a lead substrate (not shown) that supplies electrical power from the battery 4 to the IC 6.
A wiring pattern that transmits a drive signal to the step motor of the driving force transmission mechanism 3 is also formed on the circuit substrate 5.
The wiring pattern is connected to terminals 101 a and 101 b (see FIG. 3) of the step motor.
A button type compact battery for a watch is employed as the battery 4, which is disposed at a position where it overlaps with a portion of the reservoir 60 and supplies electrical power to the IC 6 via the lead substrate.
The driving force transmission mechanism 3 and the circuit substrate 5 are fixed by screwing onto the movement frame 15 by means of a fixed shaft 96, fixed to the movement frame 15, a fixing screw 91, and a fixed shaft 92.
The upper cover 13 and the lower cover 16 are both elliptical in planar shape with the cross-sectional shapes of the respective outer peripheral portions being rounded gradually and take on a substantially streamlined form when assembled.
Improvement of biocompatibility to living tissue when the fluid transportation device 1 is implanted inside a living body is taken into consideration in this shape.
Each of the upper cover 13, the lower cover 16, the tube frame 12, and the movement frame 15 have excellent biocompatibility and have a rigidity that is required for a normal state of use.
The arrangement of the driving force transmission mechanism 3 shall now be described in detail with reference to FIGS. 3 and 4.
FIG. 3 is a plan view of the watch movement that is employed as the driving force transmission mechanism 3, and FIG. 4 shows the sectional structure of the wheel train of the watch movement and the fluid transport mechanism 2.
In FIG. 3, the driving force transmission mechanism 3 has the wheel train axially supported between a first frame 11 (corresponding to a main plate in a watch) and a second frame 14 (corresponding to a train wheel bridge in a watch).
The step motor, constituted from a coil block 101, stator 102, and a step rotor 70, is also provided.
Because the arrangement of the step motor is well known, description thereof shall be omitted.
The structure of the wheel train shall now be described.
In FIGS. 3 and 4, the step rotor 70 of the step motor has a permanent magnet 70 a and is rotated by attractive and repulsive forces of the stator 102.
The rotation of the step rotor 70 is transmitted to the cam driving wheel 76 via successive engagement of a first transmission wheel 71, a second transmission wheel 72, a third transmission wheel 73, and a fourth transmission wheel 74.
Here, the second transmission wheel 72 corresponds to being a second wheel that is fitted with a second hand of a watch, the fourth transmission wheel 74 corresponds to being a minute wheel that is fitted with a minute hand of a watch, and the cam drive wheel 76 corresponds to being an hour wheel that is fitted with an hour hand of a watch.
The transmission wheels from the first transmission wheel 71 to the cam drive wheel 76 are referred to collectively as the wheel train.
The step rotor 70, the first transmission wheel 71, the third transmission wheel 73, and the fourth transmission wheel 74 are rotatably supported axially by the first frame (main plate) 11 and the second frame (train wheel bridge) 14.
A transmission wheel shaft 75 is fixed to the first frame 11, and a cylindrical portion of this shaft protrudes upward (in the direction in which the first cam 20 and the second cam 30 are disposed).
A cylindrical portion of the fourth transmission wheel 74 is inserted in a penetrating hole opened in the transmission wheel shaft 75, and an axial portion of the second transmission wheel 72 is inserted through a penetrating hole opened in the fourth transmission wheel 74.
Thus, normally, the cam drive wheel 76 makes one turn in 12 hours, and in the present embodiment, the step rotor 70 is accelerated by 45 times.
The second transmission wheel 72 has one supporting axis axially supported by the second frame 14 and has the other axis portion axially supported by the penetrating hole opened in the fourth transmission wheel 74.
The rotation of the fourth transmission wheel 74 is transmitted to the cam drive wheel 76 via a fifth transmission wheel 79 (see FIG. 3).
The cam drive wheel 76 is axially supported by an outer periphery of a cylindrical portion of the transmission wheel shaft 75 being inserted through a penetrating hole opened in the center of the cam drive wheel 76.
The axial portion 76 a of the cam drive wheel 76 protrudes in the direction in which the first cam 20 and the second cam 30 are disposed.
An upper portion of the axial portion of the cam drive wheel 76 is axially supported by a cam drive wheel supporting bearing 78 that is fixed to the upper cover 13.
A hole that axially supports the cam drive wheel supporting bearing 78 is formed in the upper cover 13, and this hole does not penetrate through the upper cover 13 and an end of the cam drive wheel supporting bearing 78 is sealed by the upper cover 13.
The cam drive wheel 76 is rotated at a predetermined rotation speed by the transmission wheels that transmit the rotation of the step rotor 70.
Because the cam drive wheel 76 is axially supported by the transmission wheel shaft 75 and the cam drive wheel supporting bearing 78, the distance between the supporting portions is made long, the tilting amount of the cam drive wheel 76 is suppressed, and a side pressure that is applied to the axial portion of the cam drive wheel 76 as a result of load torques of the first cam 20 and the second cam 30, to be described below, is lessened.
A cross-sectional structure of the fluid transport mechanism 2 shall now be described with reference to FIG. 4.
The fluid transport mechanism 2 is disposed on an upper surface of the first frame 11 so as to be overlapped with the driving force transmission mechanism 3.
The second cam 30 and the first cam 20 are fitted in that order from the lower side onto the protruding axial portion 76 a of the cam drive wheel 76.
Here, the second cam 30 is axially supported in a loosely fitted manner by the cam drive wheel 76, and the first cam 20 is axially fixed so as to rotate integrally with the cam drive wheel 76.
The tube frame 12 is disposed at the periphery of the first cam 20 and the second cam 30.
The tube frame 12 is clamped between the upper cover 13 and the first frame 11.
The upper cover 13, the tube frame 12, and the first frame 11 are screwed overlappingly together by unillustrated fixing screws and the respective connecting surfaces are put in close contact.
A structure near the bulb 80, the reservoir 60, and the outlet portion 53 of the tube 50 shall now be described with reference to the drawings.
FIG. 5 is a cross-sectional view of the structure related to fluid injection and outflow portions.
In FIG. 5, the bulb 80 has a bulb body 81, having an L-shaped flow portion, and a fluid injection plug 82, having elasticity and being press-fitted in the bulb body 81.
The injection pipe 83 is protruded from the bulb body 81 and is connected to the reservoir 60.
The fluid injection plug 82 is provided with a slit 82 b (see also FIG. 2).
A method of injecting the drug solution into the reservoir 60 shall now be described.
Injection of the drug solution into the reservoir 60 is performed by inserting an unillustrated, syringe-needle-like injection needle into the slit 82 b of the fluid injection plug 82 and injecting the drug solution into the reservoir 60.
By the slit 82 b being provided, the injection needle can be inserted readily.
When the injection needle is extracted after injection of the drug solution, the fluid injection plug 82 is closed by the elastic force of the fluid injection plug 82 itself and outflow of fluid from the bulb 80 can thereby be prevented.
Such a bulb 80 enables realization of a simple structure that does not use a valve, etc., and enables the drug solution injection operation to be performed repeatedly.
As shown in FIG. 2, when the drug solution is injected from the bulb 80, it moves in the direction of arrow F1 and then towards the fluid discharge outlet 63.
Here, because the fluid discharge outlet 63 and the fluid injection inlet 62 are separated, the occurrence of vortex flow and pulsating flow of the drug solution inside the reservoir 60 can be suppressed.
The drug solution then moves smoothly in the direction indicated by arrow F2 and into a fluid flowing portion 51 of the tube 50 from the connecting pipe 55.
An injection needle guiding portion 82 a is opened in an upper surface of the fluid injection plug 82 in consideration of guiding the inserting of the injection needle and enabling a substantially central portion of the slit 82 b to be pierced.
Close to the outlet portion 53, the tube 50 curves downward toward a center in the thickness direction of the fluid transportation device 1 and along the outer peripheral shape of the upper cover 13.
The shape of this downwardly curved portion is formed by a tube lead-out portion 132 of the upper cover 13 and a tube lead-out portion 152 of the movement frame 15.
The outlet portion 53 of the tube 50 is formed in this manner in consideration that if the fluid transportation device 1 according to this invention implanted in a living body with the tube 50 remaining in a shape that extends outward beyond the outer shape of the device, the compatibility of the tube 50 with living tissue may be compromised.
Actions of the fluid transportation device 1 according to the embodiment shall now be described with reference to the drawings.
FIG. 6 is an explanatory diagram illustrating the actions of the fluid transportation device 1.
FIG. 4 shall also be referred to the description.
First, the shapes and functions of the first cam 20 and the second cam 30 shall be described with reference to FIG. 6.
Protruding finger pressing portions 21 a to 21 c are formed at three locations of the outer periphery of the first cam 20, and a protruding finger pressing portion 32 is formed at one location of the second cam 30.
These tube pressing portions are respectively formed at equal intervals along concentric circles of equal distance from the rotation center P.
The finger pressing portions 21 a to 21 c and 32 are set to dimensions enabling the fingers 40 to 46 to occlude the tube 50.
Inclined surface portions 22 and 31 are formed in continuation to these finger pressing portions, and these inclined surface portions are provided to gradually press the fingers 40 to 46 from a state of releasing the tube 50 to a state of occluding the tube 50.
Connecting portions 23 and 36 are formed at positions at which the fingers 40 to 46 release the tube 50 and are respectively formed on concentric circles of equal distance from the rotation center P.
Furthermore, the ends of the finger pressing portions 21 a, 21 b, 21 c, and 32 are connected to the connecting portions 23 and 36 by straight lines directed toward a rotation center P (expressed by reference symbols 24 and 35 in FIG. 6).
Though the second cam 30 is axially supported in a loosely fitted relationship by the cam drive wheel 76, it is rotated by the first cam 20, which is axially fixed to the cam drive wheel 76, in the same direction (direction of arrow R).
That is, in the state in which a first cam engaging portion 38 is engaged with a second cam engaging portion 26 of the first cam 20, the rotation force of the first cam 20 is transmitted from the second cam engaging portion 26 to the first cam engaging portion 38, and the second cam 30 thus rotates along with the first cam 20.
The shapes of the fingers 40 to 46 shall now be described with reference to FIG. 4.
Because the fingers 40 to 46 have the same shape, the finger 44 shall be described as a representative example.
FIG. 4 is a cross-sectional view of the fluid transport mechanism 2 taken along positions A-A of FIG. 6.
The finger 44 has one end 44 b of an axial portion 44 rounded to a semicircular shape, and has a collar portion 44 c formed at the other end.
The end 44 b is the portion in contact with the first cam 20 and the second cam 30 and the collar portion 44 c is the tube pressing portion.
The fingers 40 to 46 are fitted in a manner enabling reciprocating movement in axial directions inside the finger guiding grooves 126 formed in the tube frame 12.
A fluid flowing action of the fluid transportation device 1 shall now be described with reference to FIG. 6.
FIG. 6 shows one state of the fluid transportation device 1.
In this state, the finger pressing portion 32 of the second cam 30 is pressing the finger 44, and the finger 44 is occluding the tube 50 (see also FIG. 4).
The fingers 45 and 46 contact the inclined surface portion 31, with the finger 45 being in a state of a slightly less tube pressing amount than the finger 44 and the finger 46 being in a state of an even less pressing amount.
The fingers 41 to 43 are in a region of the connecting portion 36 of the second cam 30 and release the tube 50.
The finger 40 is at a position at which it is beginning to contact the inclined surface portion 22 of the first cam 20 and is in a state of beginning to press the tube 50.
In this state, the drug solution from the reservoir 60 enters into the fluid flowing portion 51 of the tube 50 in the region of the fingers 40 to 43.
When the first cam 20 and the second cam 30 are rotated further in the direction of the arrow R, the finger pressing portion 32 of the second cam successively presses the fingers 45 and 46.
The finger pressing portion 21 c of the first cam 20 successively presses the fingers from the finger 40 to the finger 46.
The finger that is released from the finger pressing portion 32 or the finger pressing portion 21 c releases the tube 50.
The fingers 40 to 46 thus repeat occlusion and release according to a peristaltic movement of the fluid from the upstream side to the downstream side, and the drug solution is thereby made to flow from the reservoir 60 towards the outlet portion 53.
In the present specification, the structure that generates such a fluid flowing action is referred to as a “micropump.”
The tube 50 is held by the tube guide groove 121, formed in the tube frame 12, and a tube guide groove of the upper cover 13.
In the ranges in which the fingers 40 to 46 are disposed, recessed portions 125 and 131, which enable movement of the collar portions of the fingers, are formed respectively.
The space required for occluding and deforming the tube 50 is thereby formed.
In FIG. 4, a state in which the tube 50 is occluded is indicated by solid lines, and a released state is indicated by alternate long and two short dashed lines.
Because the respective finger pressing portions of the first cam 20 and the second cam 30 are the same in pitch and shape and the respective fingers are disposed at equal intervals, that is, because the shapes of the finger pressing portions and the inclined surface portions are set to be substantially fixed, the load torque that is applied to the cam driving wheel 76 (the load torque during one turn of the cam driving wheel 76 (the first cam 20 and the second cam 30)) is low in fluctuation.
As a specific example of the fluid transportation device 10 according to this invention, when the outer diameter of the tube 50 is 1.1 mm, the diameter of the fluid flowing portion 51 is 0.6 mm, and the rotation speed of the first cam 20 and the second cam 30 is 4 turns/hour, a continuous microscopic flow of the drug solution of 15 μl /hour is realized.
As the size of the fluid transportation device 1, a compact size of 18 mm width, 32 mm length, and 8.5 mm thickness is realized.
Thus, with the above-described first embodiment, because the components, such as the fluid transport mechanism 2, the driving force transmission mechanism 3, the battery 4, the bulb 80, the reservoir 60, etc., are sealingly housed in the casing (outer case), constituted from the upper cover 13 and the lower cover 16, when the fluid transportation device 1 is implanted in a living body, body fluids, blood, etc., do not enter inside the casing and affect the fluid transport mechanism 2 and the driving force transmission mechanism 3 and stable driving inside the living body can be sustained.
Also, by appropriately positioning the fluid transport mechanism 2, the driving force transmission mechanism 3, the battery 4, the reservoir 60, and the bulb 80 as described above, the fluid transportation device 1 can be made compact and thin and can be implanted inside a living body.
Because the fluid transportation device 1, including the tube 50, does not have components that protrude outside a living body, infection does not occur at a portion connecting the interior of the living body with the exterior and safe use is thus enabled.
Because the bulb 80 for injecting a fluid into the reservoir 60 is provided, and additional injection of the drug solution at an arbitrary timing is enabled even while the fluid transportation device 1 is being driven, continuous flow of the drug solution can be sustained without stopping driving in order to perform additional injection of the drug solution.
Also, because the driving force transmission mechanism 3 is constituted from a watch movement, compact size and thinness are realized and making the fluid transportation device 1 thin and compact can thereby be realized.
Because the watch movement, which is mass produced and includes the cam drive wheel 76, fitted with the first cam 20 and the second cam 30, is employed, a contribution to cost reduction is also made.
Because the bulb 80 is disposed so as to penetrate through the upper cover 13 in the planar space formed between the driving force transmission mechanism 3 and the fluid transport mechanism 2 and there are no members above the bulb 80 that obstruct injection operation, the injection operation of injecting the drug solution from the bulb 80 into the reservoir 60 can be performed readily.
Furthermore, in the state in which the fluid transportation device 1 is implanted inside a living body, the drug solution can be injected into the reservoir 60 from above the skin and because the fluid transportation device thus does not have to be taken out for additional injection of the drug solution, the burden on the living body can be lessened.
The drug solution inside the reservoir 60 flows from the fluid injection inlet 62, in communication with the bulb 80, toward the fluid inlet portion 52, in communication with the tube 50.
By thus disposing the fluid injection outlet 62 and the fluid inlet portion 52 separately at the upstream side and the downstream side, respectively, the occurrence of vortex flow and pulsating flow of the drug solution inside the reservoir 60 can be suppressed and a stable, continuous flow of a predetermined flow rate can be maintained.
Furthermore, because the reservoir 60 is formed of a deformable pouch and the reservoir 60 thus deforms so as to decrease in volume in accompaniment with the lowering of the internal pressure due to flow of the drug solution, the pressure inside the reservoir 60 can be kept substantially constant.
Thus, when the tube 50 is occluded by the fingers 40 to 46 and thereafter released, the drug solution is filled into the fluid flowing portion 51 in the released region and a stable flow of fluid can thus be maintained.
Because the planar shape of the casing (outer case), constituted from the upper cover 13 and the lower cover 16, is elliptical, because the outer periphery is formed to a gradual, streamlined shape, and because, even though the fluid outlet end of the tube 50 is protruded outside the casing, the fluid outlet end is extended along the outer peripheral shape of the casing, the biocompatibility of the casing and the tube 50 to living tissue is improved and injury to living tissue due to the casing and discomfort due to implantation can be suppressed when the fluid transportation device 1 is implanted in a living body.
Furthermore, an injection needle can readily be inserted into the slit 82 b of the fluid injection plug 82 that is press-fitted in the bulb 80.
When the injection needle is extracted after injection of the fluid into the reservoir 60, the slit is closed by the elastic force of the fluid injection plug 82 itself, and the outflow of fluid from the bulb can be prevented.
Such a bulb can be realized from a simple structure that does not use a valve, etc., and also provides the effect of enabling the fluid injection operation to be performed repeatedly.

Second Embodiment

FIGS. 7 to 9 show a fluid transportation device according to a second embodiment of this invention.
FIG. 7 shows an arrangement in a planar direction.
FIGS. 8A and 8B are diagrams of arrangements in a thickness direction, with FIG. 8A being a diagram as viewed from a narrow width side and FIG. 8B being a diagram as viewed from a wide width side.
FIGS. 9A to 9C are diagrams of a reservoir frame, with FIG. 9A being a plan view, FIG. 9B being a front view, and FIG. 9C being a side view.
The present embodiment is the same as the first embodiment in that a fluid transportation device, which is implanted in a living body of a human being, animal, etc., and uses a drug solution as a fluid, is described as an example, although gel-like fluids as well as gases are also included in the meaning of “fluid.”
The main points of difference of a fluid transportation device 160 according to the second embodiment shown in FIGS. 7 and 8 with respect to the fluid transportation device 1 according to the first embodiment are that a reservoir 170 is mounted onto an outer side of an outer case 161, the reservoir 170 is mounted incliningly onto the outer case, and the reservoir 170 is mounted onto the outer case via a reservoir frame 180.
In addition to this, a first cam 163, a second cam 164, a tube 165, a fluid transport mechanism (micropump) 162, constituted from seven fingers 166, and a liquid injection port (port) 167, having a fluid injection plug 168, are the same as those of the first embodiment and descriptions thereof shall be omitted.
Furthermore, a driving force transmission mechanism, circuit board,-battery, etc., which are unillustrated, are also the same as those of the first embodiment and descriptions thereof shall be omitted.
The outer case 161 has attachment portions 192 for attachment onto a subject under the skin, etc.
These attachment portions 192 are used, for example, for sewing onto the subject by a thread, etc., and are used in the same manner as in embodiments to be described later.
As illustrated, the reservoir 170 is formed of a thin pouch that swells when filled with the drug solution and can be reduced in volume when the drug solution flows out.
As the reservoir 170, one having a circular shape in plan view, being large in thickness at a central portion, and becoming lessened in thickness toward a peripheral edge is used.
However, the shape of the reservoir 170 is not limited to that illustrated and, for example, a shape that is flat at a lower surface, etc., may be used instead.
The reservoir 170 is held by the outer case 161 via the reservoir frame 180 and has a fluid injection inlet 171, which is connected to a liquid injection port 167, and a fluid discharge outlet 172, which is connected to the tube 165.
The reservoir 170, outside the outer case 161, and the tube 165, inside the outer case 161, are connected via a connecting member 173, and the outer case 161 and the connecting member 173 are sealed together to secure sealing of the interior of the outer case 161.
As shown in FIG. 8B, with the outer case 161, the position at which the reservoir 170 is mounted is set lower than the position of the liquid injection port 167 by a step 161 a, provided at a position substantially coincident to the liquid injection port 167 as viewed in a wide width direction.
Also, an inclined portion 169, which becomes lower in height toward an end at an angle X, is formed in continuation to the step 161 a.
Though the illustrated angle X is set to 17 degrees, this angle is not restricted thereto and can be set as suited.
In this inclined portion 169 is formed an opening 190, to be described below.
The reservoir 170 is held via the reservoir frame 180 so as to be set along the inclination of the inclined portion 169, and as shown in FIGS. 8A and 8A, the reservoir 170 itself is also in a state of being inclined at the angle X.
By thus inclining the reservoir 170, the end portion of the fluid transportation device 160 can, upon implantation under the skin of an animal, etc., be prevented from pulling the skin.
It is thus sufficient that the inclination angle of the reservoir 170, that is, the angle X of the inclined portion, be an angle that can suppress the pulling of the skin and this angle can be set to an angle in a range, for example, from 10 degrees to 30 degrees that is favorable according to the implantation circumstances.
Also, the inclination is not limited to an inclination in a straight line as illustrated and may be curved instead.
As shown in FIGS. 9A to 9C, the reservoir frame 180 has a substantially cylindrical shape with a curved bottom portion 180 a and has a notch 180 b and a notch 180 c formed by notching of portions of a wall portion.
As shown in FIG. 7, the notch 180 b is used for passing through the tubular fluid injection inlet 171, extending from the reservoir 170, and the notch 180 c is likewise used to pass through the tubular fluid discharge outlet 172, extending from the reservoir 170.
Though the reservoir frame 180 is formed of resin, a metal, or other hard material, it is not limited thereto in particular.
The reservoir 170 and the reservoir frame 180 are integrated by a lower surface 170 a and the bottom portion 180 a being fixed by an adhesive, etc.
The means for fixing is not limited to an adhesive.
Also, the reservoir 170 and the reservoir frame 180 do not have to be arranged as separate components and then integrated as illustrated.
For example, if, by the same material, a lower surface side can be formed to be hard and an upper surface side can be formed to be soft, an integral structure may be formed.
In this case, the hard portion at the lower surface side corresponds to being the reservoir frame 180, and the soft portion at the upper surface side corresponds to being the reservoir 170.
The bottom portion 180 a of the reservoir frame 180 is formed according to the shape of the lower surface 170 a of the reservoir 170 and is formed, for example, to be of the same curvature as the lower surface 170 a.
The bottom portion 180 a of the reservoir frame 180 is formed with the center of the bottom portion 180 a being shifted so that when the reservoir 170 is fixed, the reservoir 170 inclines at an angle X1.
Though this angle X1 is set according to the above-described inclined portion X of the outer case 160, it is not limited thereto.
Because the bottom portion 180 a is formed according to the shape of the lower surface 170 a of the reservoir 170, when, for example, the lower surface 170 a is flat, the bottom portion 180 a is also formed to be flat.
The reservoir frame 180 is also provided with a pair of hooks 181 at opposite positions of the outer peripheral surface as shown in FIGS. 9A to 9C.
Each hook 181 is formed so as to protrude outward from an upper end of the reservoir frame 180 and be curved downward.
Each hook 181 has, at its lower end portion, a hook portion 183, which is protruded substantially horizontally outward, and a guide surface 182, which extends downward and inclines inward from an outer tip of the hook portion 183.
A lower end portion (including the hook portion 183 and the guide surface 182) of each hook 181 is thus held across a gap from the outer peripheral surface of the reservoir frame 181.
Each hook 181 is also formed integrally to the reservoir frame 180 and is provided with elasticity so that the lower end portion, including the hook portion 183, can be bent toward the inner side.
Meanwhile, the outer case 161 is provided with an opening 190 for fitting the reservoir 180 onto the inclined portion 169 as shown in FIGS. 7 and 8.
The opening 190 is formed to have an inner diameter that enables fitting in of the reservoir frame 180.
At lower portions of an inner wall of the opening 190 are formed a pair of steps 191 for latching the hook portions 183 of the hooks 181 when the reservoir frame 180 is fitted.
The outer case 161 is formed so that its height decreases gradually at the opening 190 portion.
With the fluid transportation device 160 arranged as described above, the operations of discharging a fluid, contained in the reservoir 170, to the exterior and the procedure of replenishing the fluid in the reservoir 170 are the same as those of the fluid transportation device 1 of the first embodiment.
A method of assembling, especially in the vicinity of the reservoir 170 shall now be described for the second embodiment.
First, the reservoir 170, which is integrated to the reservoir frame 180, is prepared.
The fluid injection inlet 171 of the reservoir 170 is then connected to the liquid injection port 167 and the liquid discharge outlet 172 of the reservoir 170 is connected to the tube 165 (connecting member 173).
In accompaniment with this connection operation, the reservoir frame 180 is fitted into the opening 190.
In this process, the hooks 181 are put into a state in which the lower end portions thereof are bent inward by the guide surfaces 182 being guided inward by the upper end of the opening 190.
The hooks 181 protrude downward with the lower end portions being kept bent inward, and when each hook portion 183 reaches the corresponding step 191, the hook portion returns to the original state due to its own elasticity.
A state in which the hook portions 183 are latched onto the steps is thus attained and the reservoir 170 is thus held by the outer case 161 via the reservoir frame 180.
To remove the reservoir 170 for exchange, etc., the above-described procedure is carried out in reverse.
After assembly, a silicone coat is applied to the surface of the reservoir 170 and the surface of the product as a whole (the fluid transportation device 160 as a whole) to further secure innocuousness.
Thus, with the second embodiment, because the reservoir 170 is mounted on the outer side of the outer case 161, even when condensation occurs on a surface of the reservoir 170, effects on the driving force transmission mechanism and the battery can be avoided, rust formation and circuit problems can be suppressed, and durability can be improved.
Furthermore, because the reservoir 170 is held incliningly on the surface of the outer case 161, when, for example the fluid transportation device 160 is implanted under the skin, stretching of the skin by an end portion of the reservoir 170 can be avoided and discomfort after implantation can be alleviated.
Also, because the reservoir 170 is mounted in a detachable state via the reservoir frame 180, the reservoir 170 can be held reliably at a predetermined position of the outer case 161 and the operability for exchange, etc., can be improved.
Furthermore, in the case where the fluid transportation device 160 is implanted under the skin, the lower side of the reservoir 170 is protected by the hard reservoir frame 180, and by the upper side being open, the reservoir 170 can be deformed readily.
The second embodiment illustrates an example in which the reservoir 170 is held at the outer side of the outer case 161, and this invention is not limited to the embodiment shown in FIGS. 7 to 9.
For example, an embodiment is also possible in which the reservoir 170 is directly mounted onto an outer surface of the outer case 161 without using the reservoir frame 180.
In this case, the reservoir 170 is fixed onto the surface of the outer case 161 by an adhesive, etc.
The invention is also not limited to inclining the reservoir 170 as shown in FIGS. 8A and 8A.
That is, the upper surface of the outer case 161 may be made flat and not provided with the inclined portion 169, and the reservoir 170 may be held in a state of being set along the flat surface.
Also, in place of providing the liquid injection port 167 on the outer case 161, the liquid injection port 167 may be formed on a portion of the reservoir frame 180 or may be provided at a portion of the upper surface of the reservoir 170, that is for example, a central portion of the upper surface of the reservoir 170 or a portion separated from the fluid discharge outlet 172, etc.
Also, the means for detachably attaching the reservoir frame 180 to the outer case 161 is not limited to the use of hooks 181 and steps 191 and, for example, screwing means, etc., may be used to fix the reservoir frame 180 onto the outer case 161.

Third Embodiment

As the third embodiment of this invention, a drug solution feeder (fluid transportation device) for implantation under the skin of an experimental animal shall be described.
Here, a drug solution is used as the fluid, and the implantation subject is an experimental animal.
“Experimental animal” refers to a small animal, such as a mouse, rat, guinea pig, etc., on which an animal experiment concerning the drug solution can be performed.
“Drug solution” refers, for example, to a medical liquid or nutrient liquid or to any liquid for performing an animal experiment for development of such liquids or performing a medical treatment on an animal.
FIGS. 10A to 10D are external views of the drug solution feeder for implantation under the skin of an experimental animal.
FIG. 10A is a lower side view as viewed from a lower side of the drug solution feeder and is a side view as viewed from the nearer side of the paper surface of FIG. 12, FIG. 10B is an upper side view as viewed from an upper side of the drug solution feeder and is a side view as viewed from the back side of the paper surface of FIG. 12, FIG. 10C is a right side view as viewed from the right side of the drug solution feeder, and FIG. 10D is a left side view as viewed from the left side of the drug solution feeder.
FIG. 11 is an enlarged view of a right side portion in FIG. 10A of the drug solution feeder according to this invention, and is a side view of a thread retainer, by which the drug solution feeder is sewn by thread onto an experimental animal upon implantation in the experimental animal.
FIG. 12 is a plan view of the drug solution feeder and is a plan view as viewed from the upper side of the paper surface of FIG. 10A.
FIG. 13 is a cross-sectional view of principal portions taken along positions A1-A1 in FIG. 12.
FIG. 14 is a cross-sectional view of principal portions taken along positions B-B in FIG. 12.
FIG. 15 is a cross-sectional view of principal portions of a micropump unit shown in FIG. 12.
FIG. 16 is an enlarged cross-sectional view of a liquid injection port.
First, the outer appearance of the drug solution feeder 201 shall be described.
As shown in FIGS. 10A to 10D, the drug solution feeder 201 for implantation under the skin of an experimental animal has a substantially box-like outer appearance.
The breadth dimension in the longitudinal direction is approximately 34 mm, the depth dimension in the narrow width direction (lateral direction) is approximately 18 mm, and the height dimension is approximately 8.5 mm.
As an outer case of the drug solution feeder, an upper cover 202, a lower cover 203, an upper base frame (corresponding to the tube frame 12 of the first embodiment) 204, and a lower base frame (corresponding to the movement frame 15 of the first embodiment) 205 are fixed to each other.
The surface of the upper cover 202 is a skin side surface that faces the skin side when the drug solution feeder is implanted under the skin (the skin side surface that corresponds to the skin side), and the surface of the lower cover 203 is a rear surface of the skin side surface.
The materials of the upper cover 202, the lower cover 203, the upper base frame 204, the lower base frame 205, and other members that contact an experimental animal must be innocuous to the experimental animal.
Because these members are also functional members, high strength and high hardness are also required.
The materials of the upper cover 202, the lower cover 203, the upper base frame 204, the lower base frame 205, etc., of the outer case are thus, for example, synthetic resins, such as polypropylene, polystyrene, polycarbonate, etc., which are innocuous to an experimental animal, yet are high in strength and hardness, and are preferably lightweight.
After assembly, a silicone coating process is preferably applied to further secure the innocuousness.
The abovementioned materials may also be selected from the standpoint of securing biocompatibility.
The upper cover 202 is formed of a transparent material to readily enable discernment of whether the internal structure, the assembly state of parts, and the operation state are normal or abnormal.
The other outer case members of the lower cover 203, the upper base frame 204, and the lower base frame 205 are formed of a non-transparent, colored resin.
The upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 have functions of housing and holding internalized members and are members that hold a reservoir 209 that expands and contracts, for example, upon supplying or discharging of a drug solution.
Because the reservoir 209 expands and contracts as described above, it slides, for example, to some degree with respect to the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205.
As shall be described below, an arcuate tube portion 211 a of a tube 211 is successively pressed by a plurality of pressing pins 218.
This pressing force thus acts on the upper cover 202 and the upper base frame 204 that hold the pressed arcuate tube portion 211 a at the side walls.
Also, in accompaniment with the expansion and contraction of the arcuate tube portion 211 a, the arcuate tube portion 211 a slides to some degree with respect to these side walls.
The members provided with the flnctions of housing and holding the internalized members, that is for example, the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 are thus required to be high in strength and low in frictional coefficient.
The upper cover 202, the lower cover 203, the upper base frame 204, the lower base frame 205, and other members having the functions of housing and holding the internalized members may thus be filled with a filler that contributes to lowering friction.
As shall be described later, in FIG. 15, an arcuate tube portion supporting wall 224 a constitutes a tube housing portion 224 that houses the arcuate tube portion 211 a of the micropump 212.
The arcuate tube portion supporting wall 224 a is formed by the upper cover 202 and the upper base frame 204.
Here, the pressing pins 218 successively press the arcuate tube portion 21 la and this pressing force is received by the arcuate tube portion supporting wall 224 a.
The upper cover 202 and the upper base frame 204 that constitute the arcuate tube portion supporting wall 224 a may thus be filled with a filler that contributes to high strength and low friction.
The arcuate tube portion supporting wall 224 a is thereby prevented from deforming even when the arcuate tube portion 211 a is pressed by the pressing pins 218, and a stable drug solution feeding micropump that does not deteriorate with time can be provided.
The outer shape of the drug solution feeder 201 is as follows.
As shown in FIG. 10A, both left and right side faces in the longitudinal direction of the drug solution feeder 201 are inclined surfaces, by which the longitudinal direction dimension of the drug solution feeder 201 becomes narrow towards the upper side.
In FIG. 10A, the left and right side faces are respectively constituted from a longitudinal left side inclined surface 201 d at the left end and a longitudinal right side inclined surface 201 e at the right end.
When the drug solution feeder 201 is implanted under the skin of an experimental animal, the skin of the experimental animal becomes pulled according to the volume and height of the drug solution feeder 201 at both the left and right side faces of the drug solution feeder 201 and in the worst case, the skin becomes injured.
Thus, with the present embodiment, the inclined surfaces 201 d and 201 e are formed so that the above-described pull is lessened as much as possible and so that a localized shear force is not applied to the skin.
Inclination angles □1 and □2 of the inclined surfaces 201 d and 201 e are preferably in the range of 5 degrees to 60 degrees and more preferably in the range of 15 degrees to 30 degrees.
The inclination angles □1 and □2 of the inclined surfaces 201 d and 201 e may be the same or may differ.
Though inclined surfaces such as those described above do not have to be provided at side surfaces in the narrow width direction of the drug solution feeder 201 shown in FIGS. 10C and 10D, the side surfaces may be arranged as inclined surfaces by which the width is narrowed toward the upper side.
For example, a lateral left inclined surface 201 f at the left end of the narrow width direction and a lateral right inclined surface 201 g at the right end of the narrow width direction may be formed as shown in FIG. 10C.
Respective inclination angles □1 and □2 of the inclined surfaces 201 f and 201 g are preferably in the range of 5 degrees to 45 degrees and more preferably in the range of 10 degrees to 30 degrees.
The inclination angles □1 and □2 may be the same or may differ.
Though from the standpoint of reducing the pulling of the skin of an experimental animal, these inclination angles are more preferably the larger the angles, from the standpoint of internal space in the drug solution feeder 201, efficient positioning of the internalized members, and ease of holding of the drug solution feeder 201 by a hand during initial drug solution injection(the smaller angles being more preferable), and thus these angles should be determined upon comprehensive judgment from both standpoints.
In a side view (in a state of viewing from a side surface direction), upper, lower, left, and right comer portions are formed in arcuate forms in consideration of preventing injury to subcutaneous portions of an experimental animal.
As shown in FIG. 10A, left and right comer portions in the longitudinal direction of the lower cover 203 are formed as arcs of large radii, and as shown in FIG. 10C, left and right comer portions in the narrow width direction of the lower cover 203 are formed as arcs of large radii.
Likewise, as shown in FIG. 10A, left and right comer portions in the longitudinal direction of the upper cover 202 are formed as arcs of large radii, and as shown in FIG. 10C, left and right comer portions in the narrow width direction of the upper cover 202 are formed as arcs of large radii.
The arcuate portions in the longitudinal direction are formed as arcuate forms of larger radii than the arcuate portions in the narrow width direction, and the arcuate portions of the lower cover 203 are respectively formed as arcuate forms of larger radii than the arcuate portions of the upper cover 202.
The magnitudes of these radii may be in an opposite relationship from the above, or the arcuate forms may all be substantially the same in radius.
As shown in FIGS. 8, 10C, and 10D, thread retainers 207, which are attachment portions for passing thread through to fix the drug solution feeder 201 by sewing of the thread onto an experimental animal (implantation subject) under the skin of the experimental animal, are formed protrudingly at a plurality of locations.
Each thread retainer 207 has a hole 207 a for passing the thread through.
The thread retainers 207 are formed protrudingly on side surfaces of the lower cover 203 and a lower surface of each thread retainer 207 is positioned at a predetermined height h1 from the bottom surface of the lower cover 203.
This predetermined height h1 is positioned preferably at 1/10 to ½ and more preferably at ⅕ to ⅓ of the thickness of the drug solution feeder 201, that is, the thickness H from the upper/front surface of the upper cover 202 to the lower surface of the lower cover 203.
By the thread retainers 207 being at the height h1, in fixing the drug solution feeder 201 by sewing onto an experimental animal, the sewn portion of the experimental animal can be brought to a plan view position close to the thread retainers 207 and the drug solution feeder 201 can thus be drawn close to a portion immediately below it so that it is attached in a less suspended manner.
The thread retainers 207 may be formed so as to protrude from side surfaces of the lower base frame 205 instead.
In this case, the thread retainers 207 may be positioned at positions at which the predetermined height hl is secured or may be formed to protrude in plan view directions from the lower surface of the lower cover 203, that is, the bottom surface of the drug solution feeder 201.
The plan view positions at which the thread retainers 207 are formed are left and right side surface locations of the drug solution feeder 201 as shown in FIG. 12.
That is, the thread retainers 207 are formed at a total of three locations, i.e. the two locations at the right side surface of a location near the portion at which a tube 211 protrudes to the exterior and a location at the upper side of this location, and one location near the center of the left side surface.
If the formation locations at the right side surface of the thread retainers 207 are positions at opposite sides across the position of protrusion of the tube 211, the protruding portion of the tube 211 that protrudes from the side surface of the drug solution feeder 201 can be fixed and made less likely to move, and the drug solution can be supplied continuously and with stability to an experimental animal without having to move a catheter for drug solution supply to the experimental animal.
The formation locations in plan view of the thread retainers 207 are preferably at inner sides of a quadrilateral circumscribing the outermost ends of the outer case as shown in FIG. 12.
The quadrilateral circumscribing the outer case is designated as follows in FIG. 12.
That is, the quadrilateral is drawn by an upper end longitudinal direction tangent el that constitutes the maximum width of the outer case in the longitudinal direction of the drug solution feeder 201, a lower end longitudinal direction tangent e2 that constitutes the maximum width of the outer case in the same longitudinal direction, a right end narrow width direction tangent e3 that constitutes the maximum width of the outer case in the narrow width direction orthogonal to the longitudinal direction, and a left end narrow width direction tangent e4 that constitutes the maximum width of the outer case in the same narrow width direction (lateral direction).
The thread retainers 207 are positioned inside the quadrilateral surrounded by the tangents el, e2, e3, and e4 in plan view.
By the thread retainers 207 thus being positioned within the above-described quadrilateral in plan view, the thread retainers 207 are prevented from protruding outward from the side surfaces of the outer case unnecessarily and the thread retainers 207 are prevented from being pressed against an experimental animal unnecessarily and inflicting injury or discomfort on the experimental animal.
In particular, because the thread retainers 207 tend to be formed as protrusions that tend to press against the experimental animal locally and thereby inflict injury readily, keeping the thread retainers 207 within the above-described quadrilateral is an effective means for preventing such problems.
Also, as shown in FIG. 10A, a tube 211 b protrudes to the exterior from a side surface.
Though the thread retainers 207 are provided as the attachment portions in the present embodiment, this invention is not limited thereto.
For example, in place of sewing by thread onto an implantation subject, fixing by staples or an adhesive may be performed, and in such a case, the attachment portions are formed in shapes suitable for fixing by the staples or the adhesive.
FIG. 12 is a plan diagram in plan view of the drug solution feeder 201 (a view of the drug solution feeder 201 as viewed from the upper side of the paper surface of FIG. 10A).
The planar layout shall be described in outline, mainly using this plan diagram.
That is, the overall layout of the drug solution feeder 201 shall be described.
As shown in FIG. 12, the drug solution feeder 201 has, in its interior portion, a liquid injection port 208 (referred to hereinafter as the “liquid injection port” in regard to the present embodiment), a reservoir 209, a battery 210 (silver oxide battery), a tube 211 (drug solution conducting portion), the micropump 212, an integrated circuit (IC) 225 (see FIG. 13), and a circuit substrate 226 (see FIG. 13).
The liquid injection port 208 is positioned at an upper portion of substantially the center of the drug solution feeder 201 and is a portion at which the drug solution is injected into the drug solution injector 201 from the exterior.
The reservoir 209 is positioned adjacently to the left of the liquid injection port 208, is in communication with the liquid injection port 208, and stores the drug solution in its interior.
The battery 210 is partially overlapped in plan view with the reservoir 209, is positioned at the lower right of the reservoir 209, and has a flat, circular shape.
The tube 211 is positioned at substantially the right side of the drug solution injector as a whole, is in communication with the reservoir 209, and has elasticity for conducting the drug solution.
The micropump 212 is arranged substantially near the center of the tube 211.
The integrated circuit 225 has a drive circuit for the micropump 212 and a drive control circuit that controls this drive circuit.
The circuit substrate 226 has packaged thereon the integrated circuit 225 and other electronic elements as necessary and the respective electronic parts are made so as to be conductive to each other.
The liquid injection port 208 is positioned at substantially the center in the longitudinal direction (left/right direction in FIG. 12) of the drug solution injector 201.
The liquid injection port 208 is also positioned at an upper position in the narrow width direction (lateral direction) (up/down direction that is orthogonal to the longitudinal direction in FIG. 12).
The liquid injection port 208 is positioned between the reservoir 209 and the micropump 212 and at a position at which it does not overlap in plan view with the battery 210.
The micropump 212 has a rotation drive unit 214, a cam unit 217, the plurality of pressing pins 218, and the arcuate tube portion 211 a.
The cam unit 217 has a first cam 215 and a second cam 216 that are rotated by the rotation drive unit 214.
The plurality of pressing pins 218 are positioned radially at outer sides of the cam unit 217 and are moved to protrude outward successively by the cam unit 217.
The tube portion 211 a is formed in an arcuate form at a substantially central portion of the tube 211.
Though the rotation drive unit 214 of the micropump 212 is partially overlapped with the battery 210 at the left side, it is not overlapped with the reservoir 209.
The cam unit 217 and the pressing pins 218 of the micropump 212 do not overlap in plan view with the liquid injection port 208, the reservoir 209, the battery 210, and the tube 211.
The right end portion of the tube 211 is the exposed tube portion 211 b that protrudes to the exterior of the drug solution feeder 201.
A catheter (not shown) is attached to the tip of the right end portion of the tube 211 and the drug solution is injected into a body of an experimental animal via the catheter.
The above-described internalized components are supported in the planar direction and the sectional direction by the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205, which constitute the outer case, being fixed by a plurality of outer case fixing screws 213.
The outer case fixing screws 213 are screwed in from both above the upper cover 202 and below the lower cover 203 and toward guiding fittings 219 at four locations along the outer periphery of the drug solution feeder 201 as shown in FIG. 12.
The positions in planar directions of the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 are set by guide holes of these components being inserted in the guiding fittings 219.
The upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 are positioned and fixed in the sectional direction (thickness direction) by the fastening of the upper and lower outer case fixing screws 213.
The overall layout in summary is as described above.
The general cross-sectional structure of the drug solution feeder 201 and detailed structures and materials of principal portions shall now be described based on FIGS. 11 to 16.
First, as mentioned above, the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 are positioned and fixed in the sectional direction by the screwing in of the outer case fixing screws 213 from both the upper and lower sides in the cross-sectional direction.
The outer case may be constituted from just the upper cover 202 and the lower cover 203.
In this case, the upper base frame 204 and the lower base frame 205 are not exposed to outer peripheral side surfaces but are positioned at inner sides of side surface walls formed by the upper cover 202 and the lower cover 203.
The liquid injection port 208 is arranged as follows.
The liquid injection port 208 is positioned on the upper surface side of the upper cover 202.
The liquid injection port 208 is also positioned to face the skin side of the experimental animal when the drug solution feeder 201 is implanted under the skin.
A cylindrical liquid injection port protrusion 208 a of substantially circular form is protrudingly formed on the upper surface of the upper cover 202 and is provided at the inner side with an injection opening 208 b that guides a liquid injector inserted from the exterior.
The liquid injector is a syringe-needle-like injector and supplies the drug solution to the reservoir 209.
The liquid injection port protrusion 208 a is formed integrally to the upper cover 202 and is made of the same material as the upper cover 202.
The liquid injection port protrusion 208 a has the following dimensions.
In FIG. 16, an outer diameter d1 of the tip (upper end) of the liquid injection port protrusion 208 a is approximately 6.0 mm, and a height h2, from the upper surface of the upper cover 202 to the tip of the liquid injection port protrusion 208 a, is approximately 1.5 mm.
From the tip of the liquid injection port 208 a to the upper surface of the upper cover 202, a tapered inclined surface 208 c is formed so as to broaden toward a base portion.
The inclined surface 208 c has an inclination angle □ of approximately 30 degrees and its tip corner portion is curved so as not to inflict injury on the experimental animal.
An inner diameter d2 of the injection opening 208 b formed at the inner side of the inclined surface 208 c is approximately 4.0 mm.
An outer diameter d3 of a liquid injection port packing 221 disposed below is 3.0 mm.
A diameter d4 of a space 220 a disposed further below is 2.3 mm.
By the liquid injection port protrusion 208 a of the liquid injection port 208 protruding from the upper surface of the upper cover 202, the location of the liquid injection port 208 is made readily recognizable from the exterior upon implantation under the skin of the experimental animal.
That is, when after the drug solution feeder 201 is implanted under the skin of the experimental animal, the drug solution is gradually fed into the body of the experimental animal by the operation of the micropump 212 and the remaining amount of the drug solution stored in the reservoir 209 eventually becomes low, and an experimenter of the animal experiment replenishes the drug solution in the reservoir 209 by inserting the liquid injector into the liquid injection port packing 221 of the liquid injection port 208 from the exterior of the animal.
In this process, the experimenter must accurately recognize the location of the injection opening 208 b of the liquid injection port 208 from the exterior of the experimental animal.
Because with the liquid injection port 208 of the present embodiment, the liquid injection port protrusion 208 a protrudes from the upper surface of the upper cover 202 as described above and the epidermis of the experimental animal is thereby bulged locally, the experimenter can readily recognize the location of the liquid injection port 208.
The experimenter can thus insert the liquid injector into the liquid injection port packing 221 by inserting the liquid injector into the center of the bulging epidermis portion and thereby replenish the drug solution into the reservoir 208.
In the case where the epidermis of the experimental animal is bulged locally by the protruding of the liquid injection port protrusion 208 a from the upper surface of the upper cover 202 as described above, the respective dimensions of the liquid injection port protrusion 208 a are preferably set in the following ranges to enable the experimenter to recognize the location of the liquid injection port 208.
That is, the outer diameter dl of the tip (upper end) of the liquid injection port protrusion 208 a in FIG. 16 is preferably 4.0 mm to 8.0 mm and more preferably 5.0 mm to 7.0 mm.
The height h2 from the upper surface of the upper cover 202 to the tip of the liquid injection port protrusion 208 a is preferably 0.5 mm to 2.5 mm and more preferably 1.0 mm to 2.0 mm.
The inclination angle □ is preferably 5 degrees to 60 degrees and more preferably 15 degrees to 45 degrees.
The inner diameter d2 of the injection opening 208 b, formed at the inner side, is preferably 2.0 mm to 6.0 mm and more preferably 3.0 mm to 5.0 mm.
At a lower portion of the injection opening 208 b is positioned a liquid injection port frame 220, which, from the standpoint of strength and chemical resistance against the drug solution, is formed of polypropylene, ABS resin, or other synthetic resin.
A central portion of the liquid injection port frame 220 is opened, and in this opening, the liquid injection port packing 221, which is formed of silicone or other synthetic rubber having elasticity, is held by being joined to a surface of contact with the liquid injection port frame 220 by an adhesive that enables a waterproof property to be secured.
The liquid injection port packing 221 must have elasticity to enable the liquid injector that is inserted from the exterior to be inserted in readily and extracted readily.
The liquid injection port packing 221 must also have elasticity to enable the hole after extraction to become closed to reliably prevent leakage of the drug solution and entry of body fluids of the experimental animal into the interior of the feeder.
Thus, with the liquid injection port packing 221, the diameter dimension and the thickness dimension must be selected carefully along with the appropriate elasticity described above.
From the standpoint of innocuousness and biocompatibility to the experimental animal and chemical resistance against the drug solution, silicone is favorable as the material of the liquid injection port packing 221.
In the drug injection port frame 220, the space 220 a is formed at an inner portion below the liquid injection port packing 221, and in continuation to this is formed a pipe-like connecting cylinder portion 220 b that protrudes towards a side wall of the reservoir 209.
At a central portion of the connecting cylinder portion 220 b is formed a communicating path 220 c that is in communication with the space 220 a.
The reservoir 209 is arranged as a pouch that can store the drug solution in its interior and is formed of a thin, deformable synthetic resin of a thickness of approximately 0.2 mm.
When the drug solution is discharged by the micropump 212 and the drug solution is discharged from the interior of the reservoir 209, the reservoir 209 contracts, and when the drug solution is injected from the liquid injection port 208, the reservoir 209 expands.
The plan view shape and side view shape of the reservoir 209 in its maximum, expanded state are as illustrated in the respective drawings.
As the material of the reservoir 209, a material having chemical resistance against the drug solution, elasticity, high strength, and excellent gas barrier property (property of not being permeable to gases) is preferable, and among such materials, a synthetic resin is preferable.
A material having excellent gas barrier property is required to prevent entry of air and other gases from the exterior into the drug solution in the reservoir 209 and thereby prevent the mixing of hazardous substances into the drug solution as well as to prevent the lowering of the pump function of the micropump 212 due to presence of gas bubbles resulting from the entry of gas from the exterior.
Chemical resistance, elasticity, high strength, excellent gas barrier property, and a hardness of approximately 25 degrees to 40 degrees in rubber hardness are required, and as a synthetic resin that meets these requirements, an olefin-based, vinyl chloride-based, or silicone-based synthetic resin is preferable.
As shown in FIG. 12, the shape of the reservoir 209 in plan view is generally a semicircular shape.
However, as shown in FIGS. 10 and 11, a lower portion corresponding to a region that overlaps in plan view with the battery 210 is formed to be thin in thickness in cross-sectional view to avoid contact with the battery 210.
In FIG. 12, a liquid injection port connecting portion 209 a is formed at a right side of an upper portion of the reservoir 209.
The liquid injection port connecting portion 209 a has a shape that protrudes toward the liquid injection port 208 side and is joined to the connecting pipe portion 220 b of the liquid injection port 208.
A connecting pipe connecting portion 209 b is formed at a right side of a lower portion of the reservoir 209.
The connecting pipe connecting portion 209 b protrudes to the right for connection to a connecting pipe 222 that is connected to the tube 211.
A drug solution storage portion 209 c is disposed intermediate to the liquid injection port connecting portion 209 a and the connecting pipe connecting portion 209 b.
As a structure for joining the liquid injection port connecting portion 209 a and the connecting cylinder portion 220 b of the liquid injection port frame 220, ajoining structure using an adhesive or a heat sealing joining structure, with which joining is accomplished by performing heating after press fitting, is employed.
Likewise, for joining of the connecting pipe connecting portion 209 b and the connecting pipe 222, ajoining structure using an adhesive or ajoining structure, with which heat sealing is performed after press fitting, is employed.
As the material of the connecting pipe 222, a metal, such as stainless steel, etc., or a synthetic resin, such as polypropylene, vinyl chloride, etc., is favorably employed from the standpoint of having chemical resistance against the drug solution, high strength, and gas barrier property.
With the connecting pipe 222, steps of slightly large outer diameter are formed at the end at the reservoir 209 side and the other end at the tube 211 side to facilitate joining to the connecting pipe connecting portion 209 b and a connecting pipe attachment portion 211 c of the tube 211.
A drug solution conducting path, through which the drug solution can pass, is formed at a central portion of the connecting pipe 222.
As the material of the tube 211, a material having chemical resistance against the drug solution, elasticity, high strength, and excellent gas barrier property (property of not being permeable to gases) is preferable, and among such materials, a synthetic resin is preferable.
A material having excellent gas barrier property is required to prevent entry of air and other gases from the exterior into the drug solution in the tube and thereby prevent the mixing of hazardous substances into the drug solution as well as to prevent the lowering of the pump function of the micropump 212 due to presence of gas bubbles resulting from the entry of gas from the exterior.
The tube 211 is also a component member of the micropump 212.
To prevent the breakage of the tube 211 even when it is pressed by the pressing pins 218 as shall be described later, a rubber hardness (Shore A) of approximately 25 degrees to 40 degrees is necessary as the hardness of the tube 211.
As a synthetic resin having chemical resistance, elasticity, high strength, excellent gas barrier property, and an appropriate hardness, an olefin-based, vinyl chloride-based, or silicone-based synthetic resin is preferable.
Thus, the same material as that of the reservoir 209 may be selected as the material of the tube 211.
The tube 211, the material of which has been selected from such materials, is formed to have an outer diameter of 1.1 mm and an inner diameter of 0.6 mm.
The thickness of the tube 211 is thus approximately 0.25 mm.
The outer diameter, inner diameter, and thickness of the tube 211 may be changed as appropriate according to the circumstances of use.
As shown in FIG. 12, the shape of the tube 211 in plan view is a substantially semicircular arc, and at a substantially central portion thereof is formed the arcuate tube portion 211 a, and the exposed tube portion 211 b is formed at the right side.
At the left side of the tube 211 towards the reservoir 209 is formed the connecting pipe attachment portion 211 c that is connected to the connecting pipe 222.
In cross-sectional view, the tube 211 is disposed above the rotation drive unit 214 of the micropump 212 and at substantially the same height as the cam unit 217 and the pressing pins 218 as shown in FIGS. 13 and 14.
Furthermore, on the upper cover 202 and the upper base frame 204, an arcuate tube housing portion 224, of substantially the same radius as the outer shape of the arcuate tube portion 211 a of the tube 211, is formed at a portion to the outer side of the arcuate tube portion 211 a in plan view.
The outer wall of the tube housing portion 224 is arranged as the arcuate tube portion supporting wall 224 a that supports the outer wall of the arcuate tube portion 21 la.
As shown in FIG. 15, the arcuate tube portion supporting wall 224 a is arranged as a straight wall in the up/down direction.
Thus, when the arcuate tube portion 211 a is pushed outward (toward the arcuate tube portion supporting wall 224 a) by the pressing pins 218, because the arcuate tube portion supporting wall 224 a prevents the outward movement of the arcuate tube portion 211 a, the drug solution conducting path in the interior of the arcuate tube portion 211 a can be sealed substantially.
Because the pressing pins 218 are thus made by the cam unit 217 to successively press the arcuate tube portion 211 a as shown in FIG. 12, the drug solution in the tube 211 is discharged toward the exposed tube portion 211 b side.
The tube housing portion 224 may be formed on just one of either the upper cover 202 or the upper base frame 204.
In this case, the arcuate tube portion supporting wall 224 a is also formed by just one of either the upper cover 202 or the upper base frame 204.
Because a step is thus not formed at ajoint portion of the arcuate tube portion supporting wall 224 a, the arcuate tube portion 211 a can be pressed more sealingly by the pressing force of the pressing pins 218.
The exposed tube portion 211 b at the right end of the tube 211 protrudes to the exterior from a tube exposing opening 223 provided in right side walls of the upper cover 202 and the upper base frame 204.
A catheter that injects the drug solution into a blood vessel or a predetermined portion in the body of the experimental animal is attached to a tip of the tube exposing opening 223 that protrudes to the exterior.
The portion exposed to the exterior from the tube exposing opening 223 does not have to be a tube.
In this case, for example, an end portion of the tube 211 and a catheter (not shown) are connected in the interior of the tube exposing opening 223 and the tip of the catheter is protruded to the exterior from the tube exposing opening 223.
The drug solution is thereby supplied to the blood vessel of the experimental animal at the tip side of the catheter.
The connecting pipe attachment portion 211 c is fitted onto an outer portion of the connecting pipe 222 and fixed by adhesion or heat crimping.
The arcuate tube portion 211 a is formed in an arcuate shape in plan view and is disposed so as to surround the plurality of pressing pins 218 and the cam portion 217 that are disposed at a central portion of the arc in plan view.
The micropump 212 shall now be described.
The micropump 212 has the arcuate tube portion 211 a, the plurality of pressing pins 218, the cam unit 217, and the rotation drive unit 214 that rotatingly drives the cam unit 217.
The pressing pins 218 are formed of a metal or a hard synthetic resin.
The pressing pins 218 are disposed on a pressing pin guiding member (not shown).
The pressing pins 218 are thereby enabled to undergo a rectilinear motion of protruding in radial directions from a rotation center O of the cam unit 217 and returning to the original positions at the rotation center O side.
The pressing pins 218 are pushed and protruded outward in the radial directions by the cam unit 217 and are thereby made to press the arcuate tube portion 211 a against the outer wall of the tube housing portion 224.
The cam unit 217 has the first cam 215 and the second cam 216, and the first cam 215 and the second cam 216 can rotate in one direction (clockwise in FIG. 12) about the rotation center O.
The first cam 215 and the second cam 216 are formed of a polyacetal resin or other engineering plastic of high mechanical strength or a metal with excellent strength and wear resistance.
Especially in the case where a synthetic resin is used, the abovementioned filler is preferably mixed in.
As mentioned above, with a synthetic resin in which the filler is mixed, a high hardness is provided, the strength is increased, a low frictional coefficient is exhibited, and wear is less likely to occur.
The first cam 215 and the second cam 216 receive a large reaction force because the respective cam surfaces contact and press the pressing pins 218 in the radial directions to squeeze the arcuate tube portion 211 a.
Because high hardness, high strength, and low frictional coefficient are thus required of the first cam 215 and the second cam 216, the use of synthetic resin with filler mixed in is preferable.
Each of the first cam 215 and the second cam 216 has protrusions and recesses at two locations in plan view, and the protrusions at the two locations are formed at planar positions rotated by approximately 180 degrees with respect to each other.
A gradual slope portion is formed from each protrusion to a corresponding recess.
As shown in FIG. 12, in plan view, the first cam 215 and the second cam 216 have the four protrusions disposed so as to be positioned at equal intervals along the entire circumference.
That is, the protrusions of the first cam 215 and the second cam 216 are disposed at positions that are rotated by substantially 90 degrees from each other during driving of the micropump 212, that is, in the driving state of the micropump 212, which is the normal usage state after the drug solution feeder 201 has been implanted under the skin of an experimental animal.
In FIG. 12, the protrusion of the first cam 215 is pressing two pressing pins 218 outward and wide portions at the tips of the pressing pins 218 are thereby made to press the arcuate tube portion 211 a.
A central end surface of the (single) pressing pin 218, positioned adjacent to the right of the abovementioned two pressing pins 218, is contacting the slope portion of the first cam 215.
The three pressing pins 218, positioned adjacent to the left of the abovementioned two pressing pins 218, is contacting the recess of the first cam 215.
The single pressing pin 218 at the leftmost side is contacting an abovementioned slope portion of the second cam 216.
This and the three pressing pins 218 positioned adjacent to the left are hardly pressing the arcuate tube portion 211 a.
The respective pressing pins 218 are pressed back in the direction of the rotation center O by the elastic force of the arcuate tube portion 211 a.
During assembly of the drug solution feeder 201, the micropump 212 is stopped, and the first cam 215 is assembled at a position rotated by approximately 50 degrees in the clockwise direction (right direction) from the position of the first cam 215 shown in FIG. 12.
The second cam 216 is assembled at a position rotated slightly in the counterclockwise direction (left direction) from the position of the second cam 216 in FIG. 2.
Because the two protrusions of the cam 215 and the two protrusions of the cam 216 are set at positions at which the protrusions are closer to each other than when the protrusions are at the positions of FIG. 12 and the recesses of the respective cams 215 and 216 are set at positions at which the recesses face the pressing pins 218, neither of the cams press any of the pressing pins 218.
Because the drug solution feeder 201 is shipped in this state, until the drug solution feeder 201 is implanted in an experimental animal and the micropump 212 begins the rotation drive, none of the pressing pins 218 apply a pressing force to the arcuate tube portion 211 a.
Setting and deformation of the arcuate tube portion 211 a due to continuous pressing is thereby prevented to enable the elastic force to be secured over a long term.
When the drug solution feeder 201 is thereafter implanted in an experimental animal and the micropump 212 begins the rotation drive, the rotation drive axes of the rotation drive unit 214 that are engaged with the first cam 215 and the second cam 216 rotate and rotatingly drive the first cam 215 and the second cam 216.
Here, when the first cam 215 rotates and contacts the pressing pin 218 at the left end of FIG. 12, the first cam 215 slips with respect to its rotation drive axis and stays at this position until a protrusion of the second cam 216 rotates to this position.
Then, when the second cam 216 rotates, the protrusion of the second cam 216 contacts the left end of the first cam 215.
By this contact, the first cam 215 is pressed by the second cam 216 and rotates together in the clockwise direction.
The positions of the cams 215 and 216 in the respective rotation directions are thus put in the state shown in FIG. 12, and the respective protrusions of the first cam 215 and the second cam 216 are set at positions of equal intervals of substantially 90 degrees each.
Thereafter, the cams are driven rotatingly in this planar positional relationship and the respective protrusions and slope portions press the pressing pins 218 outward in the radial directions as described above.
The pressing pins 218 thus successively press the arcuate tube portion 211 a of the tube 211 outward.
The drug solution inside the tube 211 is thereby discharged to the exterior (right side in the plan view of FIG. 12).
The height positions in cross-sectional view of the first cam 215 and the second cam 216 are set to substantially the same height as the pressing pins 218 as shown in FIG. 15.
Here, in a single rotation of the first cam 215 and the second cam 216, when the respective recesses face the pressing pins 218, the first cam 215 and the second cam 216 do not press the pressing pins 218.
Setting and deformation of the arcuate tube portion 211 a due to continuous pressing is thereby prevented to enable the elastic force to be secured over a long term.
The elastic force of the arcuate tube portion 211 a does not have to be used as the elastic force that pushes the pressing pins 218 back toward the rotation center O side, and spring members may be used instead to apply this elastic force.
For example, coil springs or plate springs may be disposed between the pressing pins 218 and pressing pin guiding members (not shown).
The members that rotatingly drive the first cam 215 and the second cam 216 are the respective rotation drive axes that protrude from the rotation drive unit 214.
These rotation drive axes are engagingly mounted respectively to central holes of the first cam 215 and the second cam 216.
The respective rotation drive axes rotate about the same rotation center O and one of the rotation drive axes is inserted at the outer side of the other rotation drive axis.
As shown in FIG. 15, the respective rotation drive axes protrude upward from the rotation drive unit 214 toward the side of the first cam 215 and the second cam 216 above.
Each rotation drive axis is driven to rotate by a wheel train having various gears and pinion gear trains.
The rotation drive source of these wheel trains is a stepping motor, with which a rotor, having a bipolar permanent magnet mounted to a rotation axis, rotates at an angle of 180 degrees per step inside an opening of a stator.
In the rotation drive unit 214, the structures, used in a watch, of a step motor, a wheel train, a center wheel shaft at a terminal end of the wheel train, a cannon pinion frictionally engaged with the center wheel shaft, and an hour wheel that rotates couplingly with the cannon pinion can be employed substantially as they are.
The step motor is driven by a DC voltage of approximately 1.5 V.
Reference symbol 225 in FIGS. 13, 14, and 15 indicate an IC.
Reference symbol 226 indicates a circuit substrate.
The IC 225 is packaged on the circuit substrate 226, and a wiring pattern for electrical connection of respective electronic parts and electronic elements is formed on the surface of the circuit substrate 226.
As shown in FIG. 14, this circuit substrate 226 is packaged by being screwed onto the lower base frame 205 by means of circuit substrate fixing screws 227.
As shown in FIG. 15, external signal input ports 228 are provided at two locations on the lower surface of the lower cover 203.
As preferable locations in plan view, the external signal input ports 228 may be positioned at any locations at which there is some space from the inner surface of the lower cover 203 in cross-sectional view and which overlap in plan view with the circuit substrate 226.
More preferable positioning locations are locations in the region in plan view in which the liquid injection ports 208 and the rotation drive unit 214 are disposed and in regions peripheral to this region.
On the other hand, locations in the region in plan view in which the reservoir 209 and the battery 210 are disposed and in regions peripheral to this region are not preferable as the positioning locations.
The reason is because the reservoir 209 and the battery 210 are formed near the lower surface of the lower cover 203 in cross-sectional view.
The external signal input ports 228 are formed at inner sides of depressions formed in the lower cover 203.
Input pins 229, formed of electrically conducting material, are fixed to the lower cover 203.
When an external input terminal is pressed against an input pin 229, because the vicinity of the depressed portion of the lower cover at which the input pin 229 is fixed deforms elastically, the input pin 229 contacts the wiring pattern formed on the lower surface of the circuit substrate 226.
Program data and control signals are thereby input from the external input terminal via the input pins 229 and the wiring pattern of the circuit substrate 226 into the IC.
By the use of these input pins 229, drive characteristics and drive programs of the micropump 212 are input into the built-in IC in advance.
The input data include, for example, the time of start of discharge of the drug solution, the time of end of discharge of the same, the discharge speed of the same, the discharge amount per unit time, etc.
Though these data are preferably input before the animal experiment, the abovementioned drive characteristics may also be changed during the animal experiment.
To perform such an input change, connection cables, connected to the input pins 229, must be protruded out to the exterior of the experimental animal.
Sterilization processes to be performed during assembly shall now be described.
First, a sterilization process is applied to members that form the path through which the drug solution passes.
Here, the drug solution passage path forming members may refer, in one case, to a liquid injection unit that is formed by assembling the members together or may refer, in another case, to the respective, individual members.
In terms of workability, the sterilization process is preferably applied after assembling the members together to form the liquid injection unit.
First, the case of applying the sterilization process after assembling the members together to form the liquid injection unit shall be described.
The liquid injection unit is a unit that is formed by assembling together the liquid injection port frame 220 and the liquid injection port packing 221 of the liquid injection port 208, the reservoir 209, the connecting pipe 222, and the tube 211.
This liquid injection unit is sterilized by the application of a gas sterilization process using ethylene oxide gas.
The gas sterilization process using ethylene oxide gas shall now be described.
First, an ethylene oxide gas injector (or ethylene oxide gas feeder) is inserted into the liquid injection port packing 221 that is the entrance of the liquid injection unit.
An ethylene oxide gas injector (or ethylene oxide gas feeder) is also inserted into (connected to) the tip of the exposed tube portion 211 b of the tube 211, which is the exit of the liquid injection unit.
By both the ethylene oxide gas injector inserted into the liquid injection port packing 221 and the ethylene oxide gas injector connected to the tip of the exposed tube portion 211 b, ethylene oxide gas is injected from both the liquid injection port packing 221 side and the exposed tube portion 211 b tip side.
The drug solution passage path inside the liquid injection unit is thereby filled with ethylene oxide gas.
The interior of the liquid injection unit is thereby sterilized.
After the elapse of a predetermined time after filling with the ethylene oxide gas as described above or after the elapse of a predetermined time after injection of the ethylene oxide gas, the ethylene oxide gas is discharged out of the liquid injection unit.
This discharge may be performed from one of either the liquid injection port packing 221 side or the exposed tube portion 211 b tip side or from both sides.
The discharge of the gas may be performed by means of a suction pump or the gas may be naturally discharged.
After confirming the discharge of the gas, the tip of the exposed tube portion 211 b is sealed by heat crimping.
The sterilization process of the drug solution passage path of the liquid injection unit is thereby ended.
The heat-crimped tip of the exposed tube portion 211 b is opened at an appropriate timing close to implantation into an experimental animal and is connected to a catheter.
The ethylene oxide gas injection and discharge procedure is not limited to the above-described procedure.
For example, ethylene oxide gas may be injected by inserting the ethylene oxide gas injector into the liquid injection port packing 221, the ethylene oxide gas may be discharged as described above from the tip of the exposed tube portion 211 b, and after confirmation of the discharge, the tip of the exposed tube portion 211 b may be sealed by heat crimping.
A sterilization process is then applied to the drug solution feeder 201 as a whole, and this sterilization process shall now be described.
First, the liquid injection unit and the internalized members are assembled onto the upper cover 202, the upper base frame 204, and the lower base frame 205.
By then fastening all of the outer case fixing screws 213, the interior is sealed, and the drug solution feeder 201 is completed.
Gas sterilization by ethylene oxide gas is then applied to the entire drug solution feeder 201 in this state.
The internalized members are, for example, the battery 210, the IC 225, the circuit substrate 226, the micropump 212 (the rotation drive unit 214, the pressing pins 218, etc.), etc.
Sterilization is thus performed twice.
That is, the above-described gas sterilization process is applied upon assembly to the liquid injection unit and the above-described gas sterilization process is applied upon completion of the drug solution feeder 201.
Here, the drug solution passage path is constituted from a narrow passage and a small pouch and is thus difficult to sterilize.
Thus, for the first sterilization process, an optimal process method (gas type, gas pressure, gas injection time, etc.) is selected to enable sterilization to be performed satisfactorily even under circumstances in which sterilization is difficult.
Meanwhile, by applying the sterilization process after completion of the drug solution feeder 201, sterilization can be applied in a gas environment in which the materials of the outer case members and the internalized members will not be damaged.
As the first sterilization process applied to the liquid injection unit, a method besides the above-described gas sterilization process may be applied and, for example, a high-pressure steam sterilization process or a radiation sterilization process may be applied.
The high-pressure steam sterilization process is performed by passing high-pressure steam of approximately 130° C. through the drug solution passage path of the liquid injection unit.
That is, as in the method described above, a high-pressure steam injector (or high-pressure steam feeder) is inserted into the liquid injection port packing 221 that is the entrance of the liquid injection unit, a high-pressure steam injector (or high-pressure steam feeder) is also inserted into (connected to) the tip of the exposed tube portion 211 b of the tube 211, which is the exit of the liquid injection unit, the high-pressure steam is fed from both the liquid injection port packing 221 side and the exposed tube portion 211 b tip side, and as with the above-described discharge of the ethylene oxide gas, the high-pressure steam is discharged from the liquid injection unit.
As with the above-described discharge of the ethylene oxide gas, any of various methods may be used to discharge the high-pressure steam.
After confirming the discharge of the high-pressure steam, the tip of the exposed tube portion 211 b is sealed by heat crimping.
The sterilization process of the drug solution passage path of the liquid injection unit is thereby ended.
The heat-crimped tip of the exposed tube portion 211 b is opened at an appropriate timing close to implantation into an experimental animal and is connected to a catheter.
The high-pressure steam injection and discharge procedure is not limited to the above-described procedure.
For example, high-pressure steam may be injected by inserting the high-pressure steam injector into the liquid injection port packing 221 and be discharged as described above from the tip of the exposed tube portion 211 b, and after confirmation of the discharge, the tip of the exposed tube portion 211 b may be sealed by heat crimping.
The steam temperature is not limited to the abovementioned 130° C. and is preferably 120° C. to 150° C.
Even when it is difficult to fill or extract ethylene oxide gas due to the drug solution passage path being constituted from a narrow passage and a small pouch, steam of high pressure and high temperature can be passed through readily in the above-described high-pressure sterilization process performed on the liquid injection port frame 220 and the liquid injection port packing 221 of the liquid injection unit 208, the reservoir 209, the tube 211, the connecting pipe 222, etc.
The high-pressure steam sterilization process is not applied to the other internalized members, the cover members, and the base frame members.
This is because plastic materials are used as the materials of these internalized members, cover members, and base frame members, and these plastic materials cannot withstand the high temperature and high pressure.
Likewise, damage to the battery, which is a functional part, and the IC and other electronic parts and internalized members by application of high temperature and high pressure is prevented.
The second sterilization process applied to the entire drug solution feeder 201 after the high-pressure steam sterilization process is the same gas sterilization process described above.
The first sterilization process may be applied to the respective members prior to assembly to the liquid injection unit in a fully automatic manner without intervention of human hands in an aseptic room under aseptic conditions and the liquid injection unit may thereafter be assembled under aseptic conditions.
In this assembly process, waterproofing is preferably applied to the interior of the drug solution feeder 201 to prevent entry of body fluids of an experimental animal.
Thus, members having portions that are exposed to the exterior are bonded to each other by application of an adhesive with a waterproof function.
The adhesive, which, for example, is an ultraviolet curing adhesive, is coated onto outer peripheral contacting surfaces of the upper cover 202 and the upper base frame 204, outer peripheral contacting surfaces of the upper base frame 204 and the lower base frame 205, the contacting surfaces of the lower base frame 205 and the lower cover 203, the inner wall surface of the injection opening 208 b of the liquid injection port 208 and the upper outer peripheral wall surface of the liquid injection port frame 220, the inner wall surface of the liquid injection port frame 220 and the outer peripheral wall surface of the liquid injection port packing 221, the outer peripheral surface of the exposed tube portion 211 b at the right end of the tube 211, and the inner peripheral wall surface of the tube exposing opening 223 formed in the right walls of the upper cover 202 and the upper base frame 204.
These are fastened by screwing by the outer case fixing screws 213.
When the entire surface of the drug solution feeder 201 is illuminated by ultraviolet rays immediately thereafter, the ultraviolet curing adhesive becomes cured and a waterproof property is secured.
The waterproof property is improved by forming a silicone coat (thin film) on the outer, exposed surfaces of the outer case members (the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 in the above case) of the drug solution feeder 201.
The silicone coat may be formed on exposed outer surfaces of the assembled, completed product of the drug solution feeder.
Or the silicone coat may be formed on the respective parts of the outer case members (the upper cover 202, the lower cover 203, the upper base frame 204, and the lower base frame 205 in the above case) and the drug solution feeder may be assembled thereafter.
A method of use of the drug solution feeder 201 shall now be described.
After assembly of the feeder 201, the drive control program (for control of the drive method, drive conditions, etc., corresponding to the driving timing of the first cam 215 and the second cam 216, the drive speeds of the cams, the driving forces, etc.) of the rotation drive unit 214 of the micropump 212 is supplied to the IC via the input pins 229 of the external signal input ports 228.
Specifically, the drive control program is a program that corresponds to the drive signals of the drive start timing, drive pulse width, drive pulse output cycle, drive voltage, etc., that are provided to the driver of the stepping motor (not shown) incorporated in the rotation drive unit 214.
The drive control program may instead be stored in the IC in advance.
An injector is then inserted into the liquid injection port packing 221 of the liquid injection port 208 and initial feeding of the drug solution into the reservoir 209 is performed.
The feeder is thereafter implanted under the skin of an experimental animal.
The drug solution feeder 201 is attached by cutting open the skin of the experimental animal that has been anesthetized in advance, setting the drug solution feeder 201 under the skin with the lower cover 203 faced downward, and sewing the threads passed through the holes 207 a of the thread retainers 207 onto the experimental animal.
Because the holes 207 a of the thread retainer 207 are provided at plural locations along the periphery, the drug solution feeder 201 can be attached with stability.
The drug solution feeder 201 is then set so that the drug solution can be fed into the body, that is for example, a blood vessel of the experimental animal via a catheter attached to the tip of the tube 211 that protrudes from a side wall of the drug solution feeder 201.
Upon completion of the above preparations, the skin portion of the experimental animal is sewn together and the animal experiment is started.
The amount of drug solution fed (amount discharged into the experimental animal) by the micropump 212 is approximately 0.1 to 15 microliters per hour, and this can be set as suited in advance.
The IC may also be programmed in advance so as to vary the discharge amount according to the time elapsed during the animal experiment.
As the experimental animal moves around and some days elapse, the amount of drug solution stored in the reservoir 209 decreases.
When this decrease is recognized from the elapse of a priorly set number of days or by detection of the remaining drug solution amount in the reservoir 209 by a detecting means, an experimenter inserts a liquid injector into the liquid injection port packing 221 of the liquid injection port 208 and performs additional feeding of the drug solution into the reservoir 209.
In this process, because the experimenter can readily recognize visually the location of the surface of the experimental animal that is partially bulged by the liquid injection port 208, the drug solution can be replenished into the reservoir 209 by inserting an injector into the center of this bulged location.

Fourth Embodiment

A fourth embodiment shall now be described with reference to FIGS. 17 and 18.
Whereas in the third embodiment, the reservoir 209 and the battery 210 are partially overlapped in plan view, in the fourth embodiment, the reservoir 209 and the battery 210 are disposed so as not to overlap in plan view.
Also, whereas in the third embodiment, the arcuate tube portion 211 a, the cam unit 217, the pressing pins 218, etc., of the micropump 212 are disposed above the rotation drive unit 214, the fourth embodiment differs in that these components are oppositely disposed below the rotation drive unit 214.
In addition to the above, the fourth embodiment is the same as the third embodiment.
FIG. 17 is a plan view of principal portions of the fourth embodiment.
FIG. 18 is a cross-sectional view of principal portions taken along positions C-C in FIG. 17.
As shown in FIG. 17, the battery 210 is disposed somewhat to the left of the center in the longitudinal direction (left/right direction in FIG. 17) of the drug solution feeder 201 and at substantially the center in the narrow width direction (up/down direction in FIG. 17).
Also, as shown in FIG. 18, as the battery 210, a battery, such as a button type battery, that is thick so as to nearly contact the inner surface of the upper cover 202 and the inner surface of the lower cover 203 is employed.
The reservoir 209 is formed in a semicircular shape at the battery 210 side so as to avoid the battery 210 as shown in FIG. 17 and is formed to a thickness such that the inner surface of the upper cover 202 and the inner surface of the lower cover 203 are nearly contacted.
Because, by the above, a battery that is thick in the height direction can be employed as the battery 210, a large capacity can be secured, and because the battery capacity is large, the duration of the battery can be made long and an animal experiment can be continued over a long term.
In addition, because the reservoir 209 is not partially overlapped with the battery in plan view as in the third embodiment, a large drug solution storage capacity can be secured.
Because the efficiencies of securing of the capacities of the reservoir 209 and the battery 210 are thus improved, the drug solution feeder 201 can be made compact in plan view.
The burden placed on an experimental animal when the drug solution feeder 201 is implanted into the experimental animal can thus be lightened, thus contributing to improving the reliability of the animal experiment concerning a drug solution.
Moreover, the reservoir 209 does not have to be provided with a step portion, such as shown in FIGS. 13 and 14, for avoiding the battery 210.
Because the reservoir 209 can thus be formed of the same thickness across substantially the entire region of the drug solution storage portion so as to extend, for example, from the inner surface of the upper cover 202 to the inner surface of the lower cover 203, locations that could compromise the strength upon repeated contraction and expansion due to decrease and replenishment of the drug solution can be eliminated to enable high strength to be secured over a long term with stability.
Furthermore, because the battery 210 is formed to be thick in cross-sectional view as mentioned above, the principal portions of the liquid injection port 208 are disposed so as not to overlap with the battery 210 in plan view.
That is, the liquid injection port frame 220 and the liquid injection port packing 221 shown in FIG. 17 do not overlap with the battery 210 in plan view.
The connecting cylinder portion 220 b of the liquid injection port frame 220 that connects the liquid injection port 208 to the reservoir 209 is disposed above the battery 210 in plan view as shown in FIG. 14 and does not overlap with the battery 210 in plan view.
Likewise, the connecting cylinder 222 that connects the reservoir 209 to the micropump 212 is set below the battery 210 as shown in FIG. 17 so as to avoid the battery 210 in plan view.
As shown in FIG. 18, the arrangement in the cross-sectional view is as follows.
The connecting cylinder portion 220 b that connects the liquid injection port 208 to the reservoir 209 is connected at the upper side of the central portion of the reservoir 209 in cross-sectional view in substantially the same manner as in the third embodiment shown in FIG. 14.
The connecting pipe 222 connecting the reservoir 209 to the tube 211 is disposed below the reservoir 209 and is connected at the lower side of the central portion of the reservoir 209 in cross-sectional view as shown in FIG. 18.
Also, with the micropump 212, the connecting pipe attachment portion 211 c in communication with the connecting pipe 222, the first cam 215 and the second cam 216 that constitute the cam unit 217, the pressing pins 218, the arcuate tube portion 211 a, etc., are set at the inner surface side of the lower cover 203 in cross-sectional view, that is, at positions of substantially the same height as the connecting pipe portion 222 as shown in FIG. 18.
The exposed tube portion 211 b of the tube 211 is also positioned at the inner surface side of the lower cover 203 and protrudes to the exterior.
The micropump 212 is thus disposed upside down in the cross-sectional view direction with respect to its orientation in the third embodiment.
That is, the rotation drive unit 214, the connecting pipe attachment portion 211 c of the tube 211, the first cam 215 and the second cam 216 that constitute the cam unit 217, the pressing pin 218, the arcuate tube portion 211 a, etc., are configured upside down in the cross-sectional view direction with respect to those shown in FIGS. 14 and 15.
The circuit substrate 226 and the IC 225 are likewise disposed above the rotation drive unit 214 in cross-sectional view.
The flow of the drug solution is carried out smoothly and without strain in plan view and cross-sectional view.
That is, the drug solution storage portion 209 c of the reservoir 209 is formed at a central region of the reservoir 209 in plan view as shown in FIG. 17.
The liquid injection port 208, which can be said to be a drug solution feeding inlet, is formed at the upper side of the drug solution storage portion of the reservoir 209.
The connecting pipe 222, which can be said to be a drug solution discharge outlet, is formed at the lower side of the drug solution storage portion 209 c.
Thus, when the drug solution is injected from the liquid injection port 208 at the upper side of the drug solution storage portion 209 c, it is smoothly contained in the drug solution storage portion 209 c, and is smoothly discharged from the connecting pipe 222 at the lower side of the drug solution storage portion 209 c.
There is thus no stagnation of the drug solution and the drug solution is made to flow without strain inside the flow path.
Meanwhile, in cross-sectional view in the drug solution storage portion 209 c of the reservoir 209, when the drug solution is injected from the liquid injection port 208 at the upper side, it is smoothly contained in the drug solution storage portion 209 c, and is smoothly discharged from the connecting pipe 222 at the lower side of the drug solution storage portion 209 c as shown in FIG. 18.
Moreover, with the micropump 212, the connecting pipe attachment portion 211 c of the tube 211 in communication with the connecting pipe 222, the cam unit 217, the pressing pins 218, the arcuate tube portion 211 a, and the exposed tube portion 211 b are positioned at the inner surface side of the lower cover 203 so as to be at substantially the same height as the connecting pipe 222 and protrude to the exterior.
There is thus no stagnation of the drug solution and the drug solution is made to flow without strain inside the flow path and be discharged to the exterior.
In particular, when in implanting the drug solution feeder 201 into an experimental animal, the drug solution feeder 201 is implanted so that the lower cover 203 is set at a lower side in the vertical direction and the upper cover 202 is set at an upper side in the vertical direction, a flow path, in which the drug solution flows without strain and in accordance with gravity, is formed, and the drug solution is thus made to flow more smoothly.
Meanwhile, as shown in FIG. 17, the battery 210 is positioned at substantially the center in the narrow width direction and the longitudinal direction of the drug solution feeder 201.
The reservoir 209 and the micropump 212 are also disposed at substantially the center in the narrow width direction.
The battery 210, the reservoir 209, which contains the drug solution, and the micropump 212, especially the rotation drive unit 214, are comparatively heavy units.
By these units of large weight being disposed at substantially the center in the narrow width direction and the longitudinal direction, the fixing stability of the drug solution feeder 201 during an animal experiment in which the drug solution feeder 201 is implanted in an experimental animal is improved.
This is because the center of gravity of the drug solution feeder 201 is positioned at substantially the center in plan view of the drug solution feeder 201, and the drug solution feeder 201 is made less likely to receive an excessive acting force from the implantation portion of the experimental animal when the experimental animal moves.
The experiment is thus continued with stability.

Fifth Embodiment

A fifth embodiment differs from the third embodiment in that, as shown in the plan view of FIG. 19, the liquid injection port 208 is disposed at a central portion in the narrow width direction of the drug solution feeder 201 in plan view.
In FIG. 19, that the liquid injection port 208 is disposed at the substantially central portion in the narrow width direction of the drug solution feeder 201 means that a central position 208 d of the liquid injection port 208 is positioned at an intermediate point 201 a in the narrow width direction of the drug solution feeder 201, that is, at a position at which the distance from the upper edge in FIG. 19 and the distance from the lower edge are substantially equal.
The substantially equal position includes the condition of being within a predetermined range width 201 b from the intermediate point 201 a.
The predetermined range width 201 b is set to ⅕th a maximum width 201 c of the drug solution feeder 201.
The predetermined range width 201 b is more preferably set to 1/10th and even more preferably set to 1/15th the maximum width 201 c.
Due to the central position 208 d of the liquid injection port 208 being thus present near the intermediate point 201 a in the narrow width direction of the drug solution feeder 201, when an injector is inserted into the liquid injection port 208 to replenish a drug solution into the reservoir 209, the force of inserting the injector is prevented from being applied to an experimental animal in a direction in which the drug solution feeder 201 becomes inclined.
That is, if, for the sake of comparison, the central position 208 d of the liquid injection port 208 is located not near the intermediate point 201 a in the narrow width direction of the drug solution feeder 201 but at a biased position close to the upper edge or the lower edge, because the force of inserting the injector into the liquid injection port 208 acts on the location close to the upper edge or the lower edge, the drug solution feeder 201 will tend to incline toward the upper edge side or the lower edge side.
Replenishment of the drug solution into the liquid injection port 208 by the injector is thus made difficult, and because a localized pain due to the inclination is also inflicted on the experimental animal being replenished, the liquid injection operation tends to be hampered.
In contrast, with the present embodiment, when the injector is inserted into the liquid injection port 208 to replenish the drug solution in the reservoir 209, because the inserting force is applied substantially uniformly in the narrow width direction of the drug solution feeder 201, a localized pain is not inflicted on the experimental animal and the drug solution replenishing operation is performed smoothly.
In the plan view of FIG. 19, the reservoir 209 and the battery 210 are overlapped in plan view and this is a point of difference with respect to the third embodiment.
Also, the liquid injection port 208 is disposed between the reservoir 209 and the micropump 212 and between the battery 210 and the micropump 212.
Because the liquid injection port 208 is disposed between the reservoir 209 or the battery 210 and the micropump 212 in plan view as mentioned above, the liquid injection port 208 is positioned near a central portion of the drug solution feeder 201 even in the longitudinal direction (left/right direction in FIG. 19) of the drug solution feeder 201.
Thus, in the same manner as described above, when an injector is inserted into the liquid injection port 208 to replenish the drug solution in the reservoir 209, because the inserting force is applied substantially uniformly across the entire region direction of the drug solution feeder 201 even in the longitudinal of the drug solution feeder 201, a localized pain is not inflicted on the experimental animal and the drug solution replenishing operation is performed smoothly.
When the liquid injection port 208 is positioned at a substantially central portion in the narrow width direction and the longitudinal direction, because in extracting the injector from the liquid injection port 208, an extraction force is applied across the entire region of the drug solution feeder 201, a localized pain is not inflicted on the experimental animal and the liquid injection operation can be performed satisfactorily overall.

Sixth Embodiment

A sixth embodiment shall now be described with reference to FIGS. 20 to 26.
With the sixth embodiment, the outer shape of the drug solution feeder is modified in particular.
FIGS. 20A to 20D are external views of an outer appearance of a drug solution feeder for implantation under the skin of an experimental animal.
FIG. 20A is a lower side view as viewed from a lower side of the drug solution feeder and is a side view as viewed from the nearer side of the paper surface of FIG. 22, FIG. 20B is an upper side view as viewed from an upper side of the drug solution feeder and is a side view as viewed from the upper side of the paper surface of FIG. 22, FIG. 20C is a right side view as viewed from the right side of the drug solution feeder, and FIG. 20D is a left side view as viewed from the left side of the drug solution feeder.
FIG. 21 is an enlarged view of a right side portion in FIG. 20A of the drug solution feeder according to this invention and is also a side view of a thread retainer for sewing by thread onto an experimental animal in implanting the drug solution feeder in the experimental animal.
FIG. 22 is a plan view of the drug solution feeder as viewed from the upper side of the paper surface of FIG. 20A.
FIG. 23 is a cross-sectional view of principal portions taken along positions A2-A2 in FIG. 22.
FIG. 24 is a cross-sectional view of principal portions taken along positions B1-B1 in FIG. 22.
FIG. 25 is a cross-sectional view of principal portions of a micropump unit shown in FIG. 22.
FIG. 26 is an enlarged cross-sectional view of a liquid injection port.
First, the outer appearance of the drug solution feeder (fluid transportation device) 301 shall be described.
In FIGS. 20A to 20D the drug solution feeder 301 to be implanted under the skin of an experimental animal has a substantially box-like outer appearance.
A breadth dimension in a wide width direction (longitudinal direction) is approximately 34 mm, a depth dimension in a narrow width direction (lateral direction) is approximately 18 mm, and a height dimension is approximately 8.5 mm.
As an outer case, an upper cover 302, a lower cover 303, an upper base frame 304, and a lower base frame 305 are fixed to each other.
The material of the upper cover 302, the lower cover 303, the upper base frame 304, the lower base frame 305 and other members that come in contact with an experimental animal is required to be innocuous to the experimental animal.
In addition, these members are functional members and are thus required to be high in strength and high in hardness.
Thus, as the material of the upper cover 302, the lower cover 303, the upper base frame 304, and the lower base frame 305 that constitute the outer case, polypropylene, polystyrene, polycarbonate, or other synthetic resin that is innocuous to the experimental animal and yet is high in strength, high in hardness, and preferably lightweight is used.
After assembly, a silicone coating process is preferably applied to further secure the innocuousness.
The abovementioned materials may also be selected from the standpoint of securing biocompatibility.
The upper cover 302 is formed of a transparent material to readily enable discernment of whether the internal structure, the assembly state of parts, and the operation state are normal or abnormal.
The other outer case members of the lower cover 303, the upper base frame 304, and the lower base frame 305 are formed of a non-transparent, colored resin.
The upper cover 302, the lower cover 303, the upper base frame 304, and the lower base frame 305 have functions of housing and holding internalized members and are members that hold a reservoir 309 that expands and contracts, for example, upon supplying or discharging of the drug solution.
Because the reservoir 309 expands and contracts as described above, it slides, for example, to some degree with respect to the upper cover 302, the lower cover 303, the upper base frame 304, and the lower base frame 305.
As shall be described below, because an arcuate tube portion 311 a of a tube 311 is successively pressed by a plurality of pressing pins 318, this pressing force acts on the upper cover 302 and the upper base frame 304 that hold the pressed arcuate tube portion 311 a on the side walls thereof, and in accompaniment with the expansion and contraction of the arcuate tube portion 311 a, the arcuate tube portion 311 a slides to some degree with respect to these side walls.
The members provided with the functions of housing and holding the internalized members, that is for example, the upper cover 302, the lower cover 303, the upper base frame 304, and the lower base frame 305 are thus required to be high in strength and low in frictional coefficient.
The upper cover 302, the lower cover 303, the upper base frame 304, the lower base frame 305, and other members having the functions of housing and holding the internalized members may thus be filled with a filler that contributes to lowering friction.
As shall be described later, in FIG. 25, an arcuate tube portion supporting wall 324 a, which constitutes a tube housing portion 324 that houses the arcuate tube portion 311 a of the micropump 312, is formed by the upper cover 302 and the upper base frame 304, and because the pressing pins 318 successively press the arcuate tube portion 311 a, the arcuate tube portion supporting wall 324 a receives this pressing force.
The upper cover 302 and the upper base frame 304 that constitute the arcuate tube portion supporting wall 324 a may thus be filled with a filler that contributes to high strength and low friction.
The arcuate tube portion supporting wall 324 a is thereby prevented from deforming even when the arcuate tube portion 311 a is pressed by the pressing pins 318, and a stable drug solution feeding micropump that does not change with time can be provided.
The outer shape of the drug solution feeder 301 is as follows.
As shown in FIG. 20A, an upper/front surface of the drug solution feeder 301 is formed in a convex shape, with which a substantially central portion in the wide width direction (longitudinal direction) is the highest portion.
The upper surface shape of the upper cover 302 is thus formed in an arcuate shape of radius R1 as shown in FIG. 20A.
Meanwhile, a lower/rear surface of the drug solution feeder 301 is formed in a concave shape, with which a substantially central portion in the wide width direction (longitudinal direction) is the highest portion (is a depressed portion).
The lower surface shape of the lower cover 303 is thus formed in an arcuate shape of radius R2 as shown in FIG. 20A.
The magnitudes of these radii R1 and R2 may be set in accordance with the shape below the skin of an animal in which the drug solution feeder 301 is implanted.
R1 and R2 may be concentric or non-concentric.
FIG. 21 is an enlarged view of the right side portion in FIG. 20B.
Due to the convex shape, the substantially central portion of the upper/front surface in the longitudinal direction is raised byjust a height h31 from a boundary position between a longitudinal right side inclined surface 301 e (or a longitudinal left side inclined surface 301 e) and the upper/front surface.
This boundary position is the position of an intersection between the longitudinal right side inclined surface 301 e and an extension of the convex shape of the upper/front surface.
Due to the concave shape, the substantially central portion of the lower/rear surface in the longitudinal direction is raised by just a height h41 from lower surface positions at opposite ends of the lower/rear surface.
The shape in the narrow width direction (lateral direction) orthogonal to the longitudinal direction is as follows.
As shown in FIG. 20C, the upper/front surface of the drug solution feeder 301 is formed in a convex shape, with which a substantially central portion in the narrow width direction is the highest portion.
The upper surface shape of the upper cover 302 is thus formed in an arcuate shape of radius r1 as shown in FIG. 20C.
Meanwhile, the lower/rear surface of the drug solution feeder 301 is formed in a concave shape, with which a substantially central portion in the narrow width direction is the highest portion (is a depressed portion).
The lower surface shape of the lower cover 303 is thus formed in an arcuate shape of radius r2 as shown in FIG. 20C.
r1 and r2 may be concentric or non-concentric.
The upper/front surface shape in the longitudinal direction and the upper/front surface shape in the narrow width direction do not have to be arcuate and may be noncircular curves or combinations of straight lines.
That is, as long as the upper/front surface of the drug solution feeder 301 is formed in a convex shape such that a substantially central region in the longitudinal direction or the narrow width direction is the highest portion, the upper/front surface may be formed in any shape.
Likewise, the lower/rear surface shape in the longitudinal direction and the lower/rear surface shape in the narrow width direction do not have to be arcuate and may be noncircular curves or combinations of straight lines, and as long as the lower/rear surface of the drug solution feeder 301 is formed in a concave shape such that a substantially central region in the longitudinal direction or the narrow width direction is the highest portion (is depressed), the lower/rear surface may be formed in any shape.
The upper/front surface shape in the longitudinal direction may be formed in the above-described convex shape with the upper/front surface shape in the narrow width direction being formed in a straight-line shape, or oppositely, the upper/front surface shape in the longitudinal direction may be formed in a straight-line shape with the upper/front surface shape in the narrow width direction being formed in the above-described convex shape.
Also, the lower/rear surface shape in the longitudinal direction may be formed in the above-described concave shape with the lower/rear surface shape in the narrow width direction being formed in a straight-line shape, or oppositely, the lower/rear surface shape in the longitudinal direction may be formed in a straight-line shape with the lower/rear surface shape in the narrow width direction being formed in the above-described concave shape.
The shape of the upper/front surface in the longitudinal direction, the magnitudes of the radii R1 and R2, the height h31, and the depth h41 are set according to the shape of the skin and the subcutaneous shape of the animal in which the drug solution feeder 301 is implanted.
The shape of the upper/front surface in the narrow width direction, the magnitudes of the radii r1 and r2, the height h31, and the depth h41 are set according to the shape of the skin and the subcutaneous shape of the animal in which the drug solution feeder 301 is implanted.
By the upper/front surface being formed in the convex shape or the lower/rear surface being formed in the concave shape, the upper/front surface shape or the lower/rear surface shape of the drug solution feeder 301 is formed in a shape that is substantially in accordance with the subcutaneous shape of the animal, and thus when the drug solution feeder 301 is implanted, the drug solution feeder 301 is made readily compatible to the skin etc., and can prevent or lessen excessive pulling and injury of the animal.
Especially, by the upper/front surface being formed in the convex shape and the lower/rear surface being formed in the concave shape at the same time, the upper/front surface or lower/rear surface of the drug solution feeder 301 is enabled to be set readily along the shape of the inner surface of the skin, the subcutaneous shape, etc., of the animal that each surface contacts and the abovementioned actions and effects can be exhibited more effectively.
On the outer case, inclined surfaces, each inclining so as to become narrow in width in the wide width direction from the lower/rear surface toward the upper/front surface of the outer case, are formed at a narrow width side outer wall (first narrow width side outer wall) that is formed along the narrow width direction at one end (first end) in the wide width direction (longitudinal direction) of the drug solution feeder and at a narrow width side outer wall (second narrow width side outer wall) that is formed along the narrow width direction at the other end (second end) in the wide width direction.
That is, the inclined surfaces are formed incliningly so that the first narrow width outer wall and the second narrow width side outer wall converge from the rear surface toward the skin side surface of the outer case.
That is, the left and right side surfaces in the longitudinal direction of the drug solution feeder 301 are formed as inclined surfaces that become narrow in dimension in the longitudinal direction of the drug solution feeder 301 as the upper side is approached, and the longitudinal left side inclined surface 301 d at the left end and the longitudinal right side inclined surface 301 e are thus formed as shown in FIGS. 20A and 20B.
When these inclined surfaces 301 d and 301 e are implanted under the skin of an experimental animal, the skin of the experimental animal is pulled according to the volume and height of the drug solution feeder 301, and in the worst case, this skin becomes injured.
The inclined surfaces 301 d and 301 e are thus formed to minimize the pulling as much as possible and prevent a localized shear force from being applied to the skin.
Inclination angles □11 and □21 of the inclined surfaces 301 d and 301 e are defined so that when the drug solution feeder 301 is set on a flat planar surface, the angles that the inclined surfaces 301 d and 301 e form with respect to vertical lines orthogonal to the flat surface are the inclination angles □11 and □21.
Each of the inclination angles □11 and □21 is preferably 5 degrees to 60 degrees and especially preferably 15 degrees to 30 degrees.
The inclination angles □11 and □21 of the inclined surfaces 301 d and 301 e may be the same or may differ.
Furthermore, with the outer case, inclined surfaces, each inclining so as to become narrow in width in the narrow width direction from the lower/rear surface toward the upper/front surface of the outer case, are formed at a wide width side outer wall (first wide width side outer wall) that is formed along the wide width direction at one end (first end) in the narrow width direction of the drug solution feeder and at a wide width side outer wall (second wide width side outer wall) that is formed along the wide width direction at the other end (second end) in the narrow width direction.
That is, the inclined surfaces are formed incliningly so that the first wide width outer wall and the second wide width side outer wall converge from the rear surface toward the skin side surface of the outer case.
That is, though the side surfaces in the narrow width direction of the drug solution feeder 301 shown in FIGS. 20C and 20D do not have to be formed as inclined surfaces as described above (that is, angle □ may be 0 degrees), these side surface are preferably formed as inclined surfaces that become narrow toward the upper side, that is, formed as a width-left inclined surface 301 f and a width-right inclined surface 301 g in the narrow width direction as shown in FIG. 20C.
Inclination angles □11 and □21 of the inclined surfaces 301 f and 301 g are defined so that when the drug solution feeder 301 is set on a flat planar surface, the angles that the inclined surfaces 301 f and 301 g form with respect to vertical lines orthogonal to the flat surface are the inclination angles □11 and □21.
Each of the inclination angles □11 and □21 of the inclined surfaces 301 f and 301 g is preferably 5 degrees to 45 degrees and especially preferably 10 degrees to 30 degrees.
The inclination angles □11 and □21 of the inclined surfaces 301 f and 301 g may be the same or may differ.
In the standpoint of reducing the pulling of the skin of the experimental animal, it is preferable that the above-described inclination angles be larger. In the standpoint of efficient positioning of the internal space and the internalized members of the drug solution feeder 301 and ease of holding of the drug solution feeder 301 by a hand during the initial drug solution injection, it is preferable that the inclination angles be smaller. Thus, the inclination angles are determined taking both standpoints into consideration.
The inclined surfaces 301 d, 301 e, 301 f, and 301 g are not limited to those formed by straight lines as described above and may be formed by curves instead.
Such curves are preferably convex curves, with which central portions of the inclined surfaces 301 d, 301 e, 301 f, and 301 g are made convex.
The degrees of inclinations are preferably such that when angles, formed by tangents to the inclined surfaces 301 d, 301 e, 301 f, and 301 g at a height position of ½ a height (thickness) H1 of the drug solution feeder 301 and the vertical lines (lines in the up/down directions) in FIGS. 20A to 20D, are □11, □21, □11, and □21, these angles □11, □21, □11, and □21 are set to the above-described angles.
By forming the inclined surfaces 301 d, 301 e, 301 f, and 301 g as convex, non-straight-line surfaces, the drug solution feeder 301 is made more compatible to the animal and made to prevent excessive pulling and prevent injury.
In side view (in the state viewed from a side surface direction), the upper, lower, left, and right comers are formed in arcs in consideration of not damaging subcutaneous portions of the experimental animal.
As shown in FIG. 20A, the left and right comers in the longitudinal direction of the lower cover 301 are formed in arcs of large radii, and as shown in FIG. 20C, the left and right comers in the narrow width direction of the lower cover 303 are formed in arcs of large radii.
Likewise, as shown in FIG. 20A, the left and right comers in the longitudinal direction of the upper cover 302 are formed in arcs of large radii, and as shown in FIG. 20C, the left and right comers in the narrow width direction of the upper cover 302 are formed in arcs of large radii.
The arcuate portions in the longitudinal direction are formed in arcuate shapes of larger radii than the arcuate portions in the narrow width direction, and the arcuate portions of the lower cover 303 are formed in arcuate shapes of larger radii than the corresponding arcuate portions of the upper cover 302.
The relationship between the magnitudes of the radii may be opposite to that described above or the arcuate shapes may all be substantially the same in radius.
As shown in FIGS. 20C, 20D, and 21, thread retainers 307, which are attachment portions for passing thread through in order to fix the drug solution feeder 301 by sewing by the thread onto an experimental animal under the skin of the experimental animal, are formed protrudingly at a plurality of locations.
Each thread retainer 307 has a hole 307 a for passing the thread through.
The thread retainers 307 are formed protrudingly on side surfaces of the lower cover 303, and a lower surface of each retainer 307 is positioned at a predetermined height h11 from the bottom surface of the lower cover 303.
This predetermined height h11 is positioned preferably at 1/10 to ½ and more preferably at ⅕ to ⅓ of the thickness of the drug solution feeder 301, that is, the thickness H1 from the upper/front surface of the upper cover 302 to the lower surface of the lower cover 303.
The reason for this is because, by the retainers 307 being positioned at the height h1, in fixing the drug solution feeder 301 by sewing onto an experimental animal, the sewn portion of the experimental animal can be brought to a plan view position close to the retainers 307 and the drug solution feeder 301 can thus be drawn close to a portion immediately below it so that it is attached in a less suspended manner.
The retainers 307 may be formed so as to protrude from side surfaces of the lower base frame 305 instead.
In this case, the retainers 307 may be positioned at positions at which the predetermined height h11 is secured or may be formed to protrude in plan view directions from the lower surface of the lower cover 303, which is the bottom surface of the drug solution feeder.
The plan view positions at which the thread retainers 307 are formed are left and right side surface locations of the drug solution feeder 301 as shown in FIG. 22.
That is, the thread retainers 307 are formed at a total of three locations, i.e. the two locations at the right side surface of a location near the portion at which the tube 306 protrudes to the exterior and a location at the upper side of this location, and the one location near the center of the left side surface.
If the formation locations at the right side surface of the thread retainers 307 are positions at opposite sides across the position of protrusion of the tube 306, the protruding portion of the tube 306 that protrudes from the side surface of the drug solution feeder 301 can be fixed and made less likely to move, and the drug solution can be supplied continuously and with stability to an experimental animal without having to move a catheter for drug solution supply to the experimental animal.
The formation locations in plan view of the thread retainers 307 are preferably at inner sides of a quadrilateral circumscribing the outermost ends of the outer case as shown in FIG. 22.
The quadrilateral circumscribing the outer case is designated as follows in FIG. 22.
That is, the quadrilateral is drawn by an upper end longitudinal direction tangent e11 that constitutes the maximum width of the outer case in the longitudinal direction of the drug solution feeder 301, a lower end longitudinal direction tangent e21 that constitutes the maximum width of the outer case in the same longitudinal direction, a right end narrow width direction tangent e31 that constitutes the maximum width of the outer case in the narrow width direction orthogonal to the longitudinal direction, and a left end narrow width direction tangent e41 that constitutes the maximum width of the outer case in the same narrow width direction (lateral direction).
The thread retainers 307 are positioned inside the quadrilateral surrounded by the tangents e1, e2, e3, and e4 in plan view.
By the thread retainers 307 thus being positioned within the above-described quadrilateral in plan view, the thread retainers 307 do not protrude outward from the side surfaces of the outer case unnecessarily, and the thread retainers 307 are prevented from being pressed against an experimental animal unnecessarily and inflicting injury or discomfort on the experimental animal.
In particular, because the thread retainers 307 tend to be formed as protrusions that tend to press against the experimental animal locally and thereby inflict injury readily, keeping the thread retainers 307 within the above-described quadrilateral is an effective means for preventing such problems.
Also, as shown in FIG. 20A, the tube 311 b protrudes to the exterior from a side surface.
FIG. 22 is a plan diagram in plan view of the drug solution feeder 301 (showing the state of the drug solution feeder 301 as viewed from the upper side of the paper surface of FIG. 20A).
As shown in this plan diagram, the same arrangement as that of the third embodiment shown in FIG. 12 is employed.
As a liquid injection port 308, the reservoir 309, a battery 310, the tube 311, the arcuate tube portion 311 a, an exposed tube portion 311 b, the micropump 312, outer case fixing screws 313, a rotation drive unit 314, a first cam 315, a second cam 316, a cam unit 317, the pressing pins 318, guiding fittings 319, an integrated circuit (IC) 325, and a circuit substrate 326 in FIG. 22, the same members as 208, the reservoir 209, the battery 210, the tube 211, the arcuate tube portion 211 a, the exposed tube portion 211 b, the micropump 212, the outer case fixing screws 213, the rotation drive unit 214, the first cam 215, the second cam 216, the cam unit 217, the pressing pins 218, the guiding fittings 219, the integrated circuit (IC) 225, and the circuit substrate 226 shown in FIG. 12 are used, and thus descriptions of these members shall be omitted.
The general cross-sectional structure and the detailed structure and materials of the principal portions of the drug solution feeder 301 are shown in FIGS. 21, 22, 23, 24, 25, and 26.
These correspond to FIGS. 11, 12, 13, 14, 15, and 16 for the third embodiment.
Because descriptions of the upper cover 302, the lower cover 303, the upper base frame 304, the lower base frame 305, and the outer case fixing screws 313 shown in FIGS. 21 to 26 will be the same as the descriptions of the upper cover 202, the lower cover 203, the upper base frame 204, the lower base frame 205, and the outer case fixing screws 213 shown in FIGS. 11 to 16, descriptions of these members shall be omitted.
Also, as mentioned above, the liquid injection port 308 is the same as the liquid injection port 208 of the third embodiment, and because a description of a liquid injection port protrusion 308 a, an injection opening 308 b, an inclined surface 308 c, a liquid injection port frame 320, a space 320 a, a connecting cylinder portion 320 b, a communicating path 320 c, and a liquid injection port packing 321 will be the same as the description of the liquid injection port protrusion 208 a, the injection opening 208 b, the inclined surface 208 c, the liquid injection port frame 220, the space 220 a, the connecting cylinder portion 220 b, the communicating path 220 c, and the liquid injection port packing 221 of the third embodiment shown in FIG. 16, descriptions of these members shall be omitted.
In regard to the dimensions of the liquid injection port protrusion 308 a, because descriptions of an outer diameter d11, h21, an inclination angle □1, an inner diameter d21, an outer diameter d31, and a diameter d41 will be the same as the descriptions of the outer diameter d1, h2, the inclination angle □, the inner diameter d2, the outer diameter d3, and the diameter d4 of the third embodiment shown in FIG. 16 and thus descriptions of these members shall be omitted.
Also, the shape, material, etc., of the reservoir 309 are the same as those of the reservoir 209 of the third embodiment, and because descriptions of a liquid injection port connecting portion 309 a, a connecting pipe connecting portion 309 b, and a drug solution storage portion 309 c will be the same as the descriptions of the liquid injection port connecting portion 209 a, the connecting pipe connecting portion 209 b, and the drug solution storage portion 209 c of the third embodiment shown in FIG. 12, descriptions of these members shall be omitted.
Also, the shape, material, etc., of the tube 311 are the same as those of the tube 211 of the third embodiment, and because descriptions of the arcuate tube portion 311 a, the exposed tube portion 311 b, and a connecting pipe attachment portion 311 c is the same as the arcuate tube portion 211 a, the exposed tube portion 211 b, and the connecting pipe attachment portion 211 c of the third embodiment shown in FIGS. 12 to 16, descriptions of these members shall be omitted.
Also, the shape, material, etc., of the micropump 312 are the same as those of the micropump 212 of the third embodiment, and because descriptions of the rotation drive unit 314, the first cam 315, the second cam 316, the cam unit 317, the pressing pins 318, a tube exposing opening 323, a tube housing portion 324, the arcuate tube portion supporting wall 324 a, and a rotation center O1 will be the same as the description of the rotation drive unit 214, the first cam 215, the second cam 216, the cam unit 217, the pressing pins 218, the tube exposing opening 223, the tube housing portion 224, the arcuate tube portion supporting wall 224 a, and the rotation center O of the third embodiment shown in FIGS. 12 to 16, descriptions of these members shall be omitted.
In addition to the above, because descriptions of a connecting pipe 322, the IC 325, the circuit substrate 326, circuit substrate fixing screws 327, external signal input ports 328, and input pins 329 will be the same as the descriptions of the connecting pipe 222, the IC 225, the circuit substrate 226, the circuit substrate fixing screws 227, the external signal input ports 228, and the input pins 229 of the third embodiment shown in FIGS. 12 to 16, descriptions of these members shall be omitted.
Also, with the drug solution feeder 301 according to the sixth embodiment, because descriptions of an assembly method thereof, a sterilization process of the respective components during assembly, and a sterilization process for the entire drug solution feeder 301 will be the same as the corresponding descriptions for the drug solution feeder 201 according to the third embodiment, these descriptions shall be omitted.
Also, because a description of an application of waterproofing for preventing the entry of body fluids of an experimental animal into the interior of the drug solution feeder 301 and joining of members, with portions exposed to the exterior, to each other by attachment of an adhesive with a waterproof function for the waterproofing will be the same as the corresponding description for the drug solution feeder 201 according to the third embodiment, this description shall be omitted.
Also, because a description of a usage method of the drug solution feeder 301 will be the same as the corresponding description of the drug solution feeder 201 according to the third embodiment, this description shall be omitted.

Seventh Embodiment

A seventh embodiment shall now be described with reference to FIGS. 27 and 28.
Whereas in the sixth embodiment, the reservoir 309 and the battery 310 are partially overlapped in plan view, in the seventh embodiment, the reservoir 309 and the battery 310 are disposed so as not to overlap in plan view.
Also, whereas in the sixth embodiment, the arcuate tube portion 311 a, the cam unit 317, the pressing pins 318, etc., of the micropump 312 are disposed above the rotation drive unit 314, the seventh embodiment differs in that these components are oppositely disposed below the rotation drive unit 314.
In addition to the above, the seventh embodiment is the same as the sixth embodiment.
FIG. 27 is a plan view of principal portions of the second embodiment, and FIG. 28 is a cross-sectional view of principal portions taken along positions C1-C1 of FIG. 27.
In FIG. 28, a substantially central portion in the longitudinal direction of the upper cover 302 is formed in a convex shape that protrudes slightly upward, and the lower/rear surface of the lower cover 303 is formed in a concave shape.
With the concave shape at the lower/rear surface, a substantially central portion is formed by a horizontal straight line, a left end side is formed by a leftwardly descending straight line, and a right end side is formed by a rightwardly descending straight line.
As shown in FIG. 27, the battery 310 is disposed somewhat to the left of the center in the longitudinal direction (left/right direction in FIG. 27) of the drug solution feeder 301 and at substantially the center in the narrow width direction (up/down direction in FIG. 27).
Also, as shown in FIG. 28, as the battery 310, a battery, such as a button type battery, that is thick so as to nearly contact the inner surface of the upper cover 302 and the inner surface of the lower cover 303 is employed.
The reservoir 309 is formed in a semicircular shape at the battery 310 side so as to avoid the battery 310 as shown in FIG. 27 and is formed to a thickness such that the inner surface of the upper cover 302 and the inner surface of the lower cover 303 are nearly in contact as shown in FIG. 28.
The seventh embodiment is the same as the fourth embodiment shown in FIGS. 17 and 18, and because descriptions of the liquid port 308, the reservoir 309, the drug solution storage portion 309 c, the battery 310, the tube 311, the arcuate tube portion 311 a, the exposed tube portion 311 b, the connecting pipe attachment portion 311 c, the micropump 312, the rotation drive unit 314, the first cam 315, the second cam 316, the cam unit 317, the pressing pins 318, the liquid injection port frame 320, the connecting cylinder portion 320 b, the liquid injection port packing 321, the connecting pipe 322, the circuit substrate 326, and the IC 325 will be the same as the descriptions of the liquid injection port 208, the reservoir 209, the drug solution storage portion 209 c, the battery 210, the tube 311, the arcuate tube portion 311 a, the exposed tube portion 311 b, the connecting pipe attachment portion 311 c, the micropump 312, the rotation drive unit 314, the first cam 315, the second cam 316, the cam unit 317, the pressing pins 318, the liquid injection port frame 320, the connecting cylinder portion 320 b, the liquid injection port packing 321, the connecting pipe 322, the circuit substrate 326, and the IC 325 of the fourth embodiment shown in FIGS. 17 and 18, the descriptions of these members shall be omitted.

Eighth Embodiment

An eighth embodiment differs from the sixth embodiment in that, as shown in the plan view of FIG. 29, the liquid injection port 308 is disposed at a central portion in the narrow width direction of the drug solution feeder 301 in plan view.
The arrangements of other portions, especially the outer shape of the outer case of the drug solution feeder, are the same as those of the sixth embodiment.
The seventh embodiment is the same as the fifth embodiment shown in FIG. 19, and because descriptions of an intermediate point 301 a, a predetermined range width 301 b, maximum width 301 c, the liquid injection port 308, a central position 308 d, the reservoir 309, the battery 310, and the micropump 312 in FIG. 29 will be the same as the descriptions of the intermediate point 201 a, the predetermined range width 201 b, the maximum width 201 c, the liquid injection port 208, the central position 208 d, the reservoir 209, the battery 210, and the micropump 212 of the fifth embodiment shown in FIG. 19, the descriptions of these members shall be omitted.

Ninth Embodiment

A ninth embodiment shall now be described with reference to FIG. 30.
Because with the outer case, the substantially central portion of the upper/front surface in the wide width direction of the drug solution feeder is formed in a convex surface or the substantially central portion of the lower/rear surface in the wide width direction of the drug solution feeder is formed in a concave surface or both the convex surface and the concave surface are formed, the shapes of the internal components can be configured in a modified manner.
As shown in FIG. 30, with the ninth embodiment, by a substantially central portion of the lower/rear surface of the lower cover 303 being formed in a concave surface, a lower portion of the reservoir 309 can be formed to extend downward.
FIG. 30 is a cross-sectional view of principal portions of the drug solution feeder 301 corresponding to FIG. 23.
In FIG. 30, when the left and right end sides in the longitudinal direction of the lower cover 303 are formed to protrude in the downward direction with respect to FIG. 23, the lower portion of the reservoir 309 at the outer left end portion that does not overlap with the battery 310 in plan view is extended downward, thereby forming a lower extended portion 309 g.
Thus, a volume that is larger by the amount corresponding to the lower extended portion 309 g can be secured for the reservoir 309.
The extended portion of the reservoir 309 is not limited to the above and may be another portion instead.
For example, when the opposite end sides in the narrow width direction of the lower cover 303 are protruded in the downward direction with respect to FIG. 23, the opposing ends of the reservoir 309 in the narrow width direction that do not overlap with the battery 310 in plan view may be extended downward.
Or, when a substantially central portion in the longitudinal direction of the upper/front surface of the upper cover 302 is convex, an upper portion of the reservoir 309 corresponding to the convex shape of the central portion may be formed to protrude in the upward direction along the convex shape.
Or, when a substantially central portion in the narrow width direction of the upper/front surface of the upper cover 302 is convex, the upper side of the reservoir 309 may be formed to protrude in correspondence to the convex shape.

Tenth Embodiment

A tenth embodiment shall now be described with reference to FIG. 31.
Because with the outer case, the substantially central portion of the upper/front surface in the wide width direction of the drug solution feeder is formed in a convex surface or the substantially central portion of the lower/rear surface in the wide width direction of the drug solution feeder is formed in a concave surface or both the convex surface and the concave surface are formed, the shapes of the internal components can be configured in a modified manner.
The tenth embodiment provides a modification example in which an up/down direction axis of the reservoir 309 is inclined with respect to an up/down direction axis 311 h of the drug solution feeder 301 and an up/down direction of the micropump 312 is also inclined as shown in FIG. 31.
FIG. 31 is a cross-sectional view of principal portions corresponding to FIG. 28.
When the drug solution feeder 301 is set on a planar flat surface, the up/down direction axis 311 h of the drug solution feeder 301 is a vertical axis that is orthogonal to the flat surface.
In FIG. 31, the lower/rear surface of the lower cover 303 is formed in a concave surface such that the central portion in the longitudinal direction is concave.
A central lower/rear surface 303 c is formed at a central portion of the lower/rear surface of the lower cover 303, a left lower/rear surface 303 d and a right lower/rear surface 303 e are formed to the left and right, respectively, of the central lower/rear surface 303 c, and each of the central lower/rear surface 303 c, the left lower/rear surface 303 d, and the right lower/rear surface 303 e is formed in a substantially straight-line form.
Each of the central lower/rear surface 303 c, the left lower/rear surface 303 d, and the right lower/rear surface 303 e may be formed instead in an arcuate form.
Meanwhile, a central upper/front surface 302 c is formed at a central portion of the upper surface of the upper cover 302, a left upper/front surface 302 d and a right upper/front surface 302 e are formed to the left and right, respectively, of the central upper/front surface 302 c, and each of the central upper/front surface 302 c, the left upper/front surface 302 d, and the right upper/front surface 302 e is formed in a substantially arcuate form.
Each of the central upper/front surface 302 c, the left upper/front surface 302 d, and the right upper/front surface 302 e may be formed instead in a straight-line shape.
Here, the up/down direction axis 309 h of the reservoir 309 is substantially orthogonal to the left lower/rear surface 303 d of the lower cover 303 and is thus inclined toward the left at a reservoir inclination angle □1 with respect to the up/down direction axis 311 h of the drug solution feeder 301 that is orthogonal to the central lower/rear surface 303 c of the lower cover 303.
Likewise, the up/down direction axis 312 a of the micropump 312 is substantially orthogonal to the right lower/rear surface 303 e of the lower cover 303 and is thus inclined toward the right at a micropump inclination angle □2 with respect to the up/down direction axis 311 h of the drug solution feeder 301 that is orthogonal to the central lower/rear surface 303 c of the lower cover 303.
Because the reservoir 309 and the micropump 312 are thus disposed with the respective up/down axes being inclined so as to be substantially orthogonal to the concave surface of the lower/rear surface of the lower cover 303 and the convex surface of the upper/front surface of the upper cover 302 that constitute the outer case, the reservoir 309 and the micropump 312 can be positioned with hardly any gap with respect to the inner surface of the outer case and a thin drug solution feeder can thus be realized.
Because a thin form can thus be realized while realizing lessening of discomfort and minimizing injury to an animal by making the upper/front surface of the outer case a convex surface and the lower/rear surface a concave surface, injuring of the animal can be lessened further.

Eleventh Embodiment

An eleventh embodiment shall now be described with reference to FIGS. 32A to 32D.
The shapes of the upper/front surface and the lower/rear surface of the outer case are not limited to those described above.
The eleventh embodiment is arranged as shown in FIGS. 32A to 32D.
In FIG. 32A, in the longitudinal direction, a substantially central portion of the upper/front surface of the upper cover 302 is formed in a convex surface, and the lower/rear surface of the lower cover 303 is formed in a straight-line shape.
In FIG. 32B, in opposition to the arrangement shown in FIG. 32A, the upper/front surface of the upper cover 302 is formed in a straight-line shape, and a substantially central portion of the lower/rear surface of the lower cover 303 is formed in a concave shape.
In FIG. 32C, in the narrow width direction, a substantially central portion of the upper/front surface of the upper cover 302 is formed in a convex surface, and the lower/rear surface of the lower cover 303 is formed in a straight-line shape.
In FIG. 32D, in opposition to the arrangement shown in FIG. 32C, the upper/front surface of the upper cover 302 is formed in a straight-line shape, and a substantially central portion of the lower/rear surface of the lower cover 303 is formed in a concave shape.
Combinations besides the above are also possible.
By these arrangements, discomfort to an animal is eliminated further when the drug solution feeder is incorporated in the animal.
In regard to the inclined surfaces, this invention is not limited to the forms described with the sixth to eleventh embodiments, and it is sufficient that an inclined surface be formed at least at a portion of the outer walls spanning from the skin side surface, which is the surface of the upper cover 302, to the rear surface, which is the surface of the lower cover 303.
For example, as has been mentioned above, though in the sixth embodiment shown in FIGS. 20A to 20D, all of the outer walls (side surfaces) are arranged as the inclined surfaces 301 d, 301 e, 301 f, and 301 g, an embodiment is also possible in which just the inclined surfaces 301 d and 301 e are left and the other outer walls are made non-inclined (by setting □11 and □21 to 0 degrees).
In this case, the outer walls in the wide width direction at which the inclined surfaces 301 f and 301 g were formed are formed in substantially vertical surfaces.
The substantially vertical surfaces become the vertical hold surfaces to be described below.
With this embodiment, after the drug solution feeder 301 is implanted under a skin, the substantially vertical surfaces (vertical hold surfaces) can be held readily via the skin and the drug solution feeder 301 in the implanted state can be fixed readily.
The position of the liquid injection port 308 can thus be fixed readily in replenishing the drug solution into the reservoir 309, and the position into which an injection needle is to be inserted can thereby be clarified to improve the workability.
An embodiment is also possible in which just the inclined surfaces 301 f and 301 g, among the inclined surfaces 301 d, 301 e, 301 f, and 301 g, are left and the other outer walls are made non-inclined (by setting □11 and □21 to 0 degrees).
An embodiment is also possible in which one of the inclined surfaces 301 d, 301 e, 301 f, and 301 g is formed as an inclined surface and the other outer walls are made substantially vertical surfaces that are non-inclined.
An embodiment is also possible in which a vertical hold surface, such as that described above, is provided at a portion of an inclined surface.
To describe using the sixth embodiment shown in FIGS. 20A to 20D, intermediate portions of the inclined surfaces 301 f and 301 g may be formed to be substantially vertical partially (by setting □11 and □21 to 0 degrees).
In this case, the inclined surfaces 301 f and 301 g are formed at opposite sides of the respective substantially vertical surfaces, and these vertical surfaces become the vertical hold surfaces.
Modification examples and application examples that can be applied to the respective embodiments shall now be described.

MODIFICATION EXAMPLE 1

FIG. 33 is a cross-sectional view of principal portions of the liquid injection port unit 208 that illustrates a modification example of the liquid injection port 208 (including the liquid injection port 308).
Whereas the liquid injection port protrusion 208 a in FIG. 16 is made integral in color tone with the upper cover 202 in FIG. 16, the liquid injection port protrusion 208 a in FIG. 33 is differed in color tone from the upper cover 202.
In terms of color tone, whereas the upper cover 202 is formed of a colorless, transparent material, the liquid injection port protrusion 208 a in FIG. 33 is formed of a red material.
The liquid injection port protrusion 208 a may thus be arranged as a separate member from the upper cover 202 and these components may be bonded at a contact surface by an adhesive with a waterproof property, etc., or a red synthetic resin may be formed on the upper cover 202 to form the liquid injection port protrusion 208 a integrally from resin.
Because the liquid injection port protrusion 208 a is made red in color and thus differed in color tone from the upper cover 202, when the drug solution feeder 201 is implanted under a skin of an experimental animal, the red color of the liquid injection port protrusion 208 a can be visually recognized readily from the exterior, thus enabling an experimenter to readily recognize the location of the liquid injection port 208 and readily insert an injector into the liquid injection port 208.
Here, the color tone of the liquid injection port protrusion 208 a is not limited to a red-based color tone, and the color tone may be any color tone that is readily recognizable from the exterior by an experimenter, and may be a blue-based or black-based color tone, etc.
In FIG.33, a removal preventing collar 220 d that prevents the liquid injection port packing 221 from becoming removed is provided at an upper end of the liquid injection port frame 220.
Structures besides the above are formed in the same manner as in FIG. 16.

MODIFICATION EXAMPLE 2

FIG. 34 is a cross-sectional view of principal portions of the liquid injection port unit 208 that illustrates another modification example of the liquid injection port 208 (including the liquid injection port 308).
With the liquid injection port 208 in FIG. 34, a guiding inclined surface 220 e, which serves as a guide for inserting in an injector from the exterior, is provided at an upper end of the liquid injection port frame 220.
An inclination angle □ of this guiding inclined surface is formed in the direction of spreading toward the upper side and is preferably 5 degrees to 30 degrees and more preferably 10 degrees to 20 degrees.

MODIFICATION EXAMPLE 3

FIG. 35 is a cross-sectional view of principal portions of the liquid injection port unit 208 that illustrates yet another modification example of the liquid injection port 208 (including the liquid injection port 308).
In FIG. 35, the liquid injection port 208 does not have a protrusion protruding from the upper surface of the upper cover 202.
That is, the liquid injection port protrusion 208 a, such as that shown in FIGS. 14 and 16, is not present.
The upper end of the liquid injection port frame 220 is thus formed so as to be kept at a height no more than the upper surface of the upper cover 202.
When the liquid injection port 208 is thus not protruded from the upper surface of the upper cover 202, there is no need to make the skin of an experimental animal become protruded, and the burden on the experimental animal is lightened.
However, because it becomes difficult for an experimenter to find the location of the liquid injection port 208 in the process of supplying the drug solution, the color tone of the liquid injection port frame 220 must be differed from the color tone of the upper cover 202 as in the Modification Example 1.

MODIFICATION EXAMPLE 4

The micropump 212 (312) is not limited to the type described above.
That is, the micropump may be of any type as long as the drug solution is appropriately fed and discharged from the reservoir 209 (309) to the exterior.
For example, the structures of the rotation drive unit 214 (314) and the cam unit 217 (317) may be the same as those disclosed in Japanese Patent No. 3702901.
Also, though with the rotation drive unit 214 (314), a watch movement that drives the hands of a watch is used and step driving of the step motor thereof is performed by the drive control means according to priorly determined drive signals or a control program to rotatingly drive the cam unit, the rotation drive unit may be of an arrangement in addition to the above.
Also, the pump structure that successively presses the tube 211 (311) to deliver the drug solution may be of any structure or system.
For example, the micropump may be one with which the tube is successively pressed locally by a plurality of metal balls that rotate along the tube while being kept at predetermined intervals and the drug solution that is present between the portions of the tube at the predetermined intervals of the plurality of balls is discharged.

MODIFICATION EXAMPLE 5

Though the battery 210 (310) in each of the embodiments may be a silver oxide battery, lithium battery, or other type that is disposable as a primary battery, the battery may also be a rechargeable secondary battery.
In this case, recharging terminals must be formed, for example, on the lower cover 203 (302) of the drug solution feeder 201 (301).
The secondary battery can be recharged by connecting connection terminals of an external charger to the recharging terminals and the drug solution feeder 201 (301) can thereby be used over a long term or reused.
As the battery 210 (310) in each of the embodiments described above, a battery that outputs a DC voltage of 1.5V is used.
Another power supply besides a battery may be used instead.

MODIFICATION EXAMPLE 6

Instead of the above-described waterproofing, a waterproof structure may be employed to prevent the entry of body fluids of an experimental animal into the interior of the drug solution feeder.
For example, in each embodiment, microprotrusions are formed along the entire periphery of the drug solution feeder on at least one of the contacting surfaces among each set of the mutual outer peripheral contacting surfaces of the upper cover 202 (302) and the upper base frame 204 (304), the mutual outer peripheral contacting surfaces of the upper base frame 204 (304) and the lower base frame 205 (305), and the mutual contacting surfaces of the lower base frame 205 (305) and the lower cover 203 (303).
These microprotrusions are formed at the inner peripheral side of the outer case fixing screws 213 (313) that are tightened to fix outer case members.
By then tightening the outer case fixing screws 213 (313), the respective contacting surfaces are press-contacted to each other, and because the upper cover 202 (302), the upper base frame 204 (304), the lower base frame 205 (305), and the lower cover 203 (303) are formed of synthetic resin, the microprotrusions are squashed by the press contact, thereby realizing a waterproof structure.
The microprotrusions may instead be fused by heating by ultrasonic vibration.
In the above cases, the injection opening 208 b (308 b) of the liquid injection port 208 (308) and the upper outer peripheral wall surface of the liquid injection port frame 220 (320), the inner wall surface of the liquid injection port frame 220 (320) and the outer peripheral wall surface of the liquid injection port packing 221 (321), and the outer peripheral surface of the exposed tube portion 211 b (311 b) at the right end of the tube 211 (311) and the inner peripheral wall surface of the tube exposing opening 223 (323) formed in the right walls of the upper cover 202 (302) and the upper base frame 204 (304) are preferably adhered together by the ultraviolet curing adhesive described above.
As another type of waterproof structure, a waterproof packing structure, in which waterproof packings are press-contacted at the contacting portion of the respective members, may also be employed.
For example, by forming waterproof packing positioning grooves from synthetic rubber along the circumferences of the outer peripheral contacting surfaces of the upper cover 202 (302) and the upper base frame 204 (304), the outer peripheral contacting surfaces of the upper base frame 204 (304) and the lower base frame 205 (305), the contacting surfaces of the lower base frame 205 (305) and the lower cover 203 (303), the contacting surfaces of the injection opening 208 b (308 b) of the liquid injection port 208 (308) and the upper outer periphery of the liquid injection port frame 220 (320), and the outer peripheral surface of the exposed tube portion 211 b (311 b) at the right end of the tube 211 (311) and the inner peripheral wall surface of the tube exposing opening 223 (323) formed in the right walls of the upper cover 202 (302) and the upper base frame 204 (304) and, upon inserting waterproof packings in the positioning grooves, assembling, and tightening the outer case fixing screws 213 (313), a waterproof structure is obtained by the respective waterproof packings being elastically pressed.

MODIFICATION EXAMPLE 7

With the drug solution feeder 201 (including the drug solution feeder 301), the reservoir 209 is set to expand and contract and become deformed in outer shape when the drug solution is fed in the above-described manner via the liquid injection port 208 into the reservoir 209 of the above-described material and thickness and when the drug solution is discharged by the micropump 212.
For example, when the reservoir 209 is filled with the drug solution, the reservoir 209 is expanded and takes on an expanded outer shape, that is, the plan view shape and the side view shape shown in FIGS. 12, 13, and 14.
As the drug solution is thereafter discharged by the micropump 212, the reservoir 209 contracts gradually and the outer shape thereof becomes a contracted outer shape.
If the outer shape of the reservoir 209 is set so as not to change even when the drug solution is discharged from the reservoir 209 by the micropump 212, a space, corresponding to the volume of the discharged drug solution, will form inside the reservoir 209.
This space will be in a substantially vacuum state.
When the drug solution feeding operation by the micropump 212 is continued thereafter, the drug solution becomes difficult to discharge and control of drug solution feeding (feeding amount, feeding speed, etc.) becomes difficult.
This is because a counteracting force due to the vacuum state of the space inside the reservoir 209 acts against the drug solution feeding force of the micropump 212.
Thus, the more the drug solution is discharged from the reservoir 209, the greater the counteracting force, and the drug solution feeding control is made more difficult.
Thus, in order to make-an improvement regarding the drug solution feeding control being made more difficult, the reservoir 209 is preferably enabled to contract in accompaniment with the discharge of the drug solution from the reservoir 209.
FIG. 36 shows a modification example that is arranged so that the reservoir 209 can contract.
FIG. 36 is a cross-sectional view as viewed from substantially the same direction as FIG. 14.
In contrast to FIG. 14, the reservoir 209 and the battery 210 are illustrated without omission in the left/right direction.
In FIG. 36, the reservoir 209 is arranged in the same manner as in FIG. 14, and the material and thickness thereof are also substantially the same as those in FIG. 14.
In FIG. 36, because most of the drug solution has been discharged from the reservoir 209 by the micropump 212, an upper side wall 209 d of the reservoir 209 droops down to a drooped position 209 e, indicated by solid lines.
The drooped position 209 e descends to a position at which the upper side wall 209 d substantially contacts a lower side wall 209 f of the reservoir 209.
In this state, the drug solution has been discharged by the micropump 212 and only a slight amount is present in the reservoir 209.
Meanwhile, a deformable upper cover portion 230, which is elastically deformable, is formed on a planar region of the upper cover 202 that opposes the reservoir 209 in plan view.
The material of the deformable upper cover portion 230 is the same as that of the reservoir 209 and is, specifically, an olefin-based, vinyl-chloride-based, or silicone-based synthetic resin that is excellent in chemical resistance, elasticity, high strength, and gas barrier property and has a rubber hardness of approximately 25 degrees to 40 degrees, and the thickness thereof is set to 0.2 mm.
With the deformable upper cover portion 230, an outer peripheral surface 230 b of an outer peripheral thick portion 230 a at the outer periphery is joined by an adhesive or joined by heat fusion to an inner peripheral surface of an opening of the upper cover 202 to secure a waterproof property.
A substantially central portion of the deformable upper cover portion 230 is arranged as a central thin portion 230 c.
As shown in FIG. 36, though as most of the drug solution in the reservoir 209 becomes discharged, the pressure at the inner side of the deformable upper cover portion 230, that is, the interior of the drug solution feeder 201 drops and the upper side wall 209 d of the reservoir 209 thus tends to deform downwards, this downward deformation is prevented by the pressure drop that occurs at the upper side.
In this process, the central thin portion 230 c becomes elastically deformed inward (downward in FIG. 36) by the pressure drop at its inner side and droops down to a lower position 230 d.
The pressure at the inner side of the thin portion 230 c thus hardly drops and the drooping of the upper side wall 209 d of the reservoir 209 is thus not prevented.
The lowering of the pressure inside the reservoir 209 is thus prevented, and the discharge of the drug solution by the micropump 212 is performed smoothly.
When the interior of the reservoir 209 is filled with the drug solution, the central thin portion 230 c of the deformable upper cover portion 230 is positioned at the upper side and the side view shape thereof is a bellows shape as indicated by alternate long and two short dashes lines in FIG. 36.
This is because the deformable upper cover portion 230 is thereby made elastically deformable more readily to the lower position 230 d.
The shape of the thin portion 230 c when the interior of the reservoir 209 is filled with the drug solution is not restricted to a bellows shape and may be horizontal instead.
That is, any material or shape may be employed as long as the deformable upper cover portion 230 can elastically deform readily to the lower position 230 d.
This invention is not limited to the structure of the deformable upper cover portion 230, which is elastically deformable and is provided at the upper cover 202, and any structure may be employed by which the outer case portion of the drug solution feeder 201 deforms elastically inward in accordance with the pressure drop inside reservoir 209 when the drug solution in the reservoir 209 is discharged.
For example, an opening in communication with the exterior may be provided in the outer case portion of the drug solution feeder 201 so as to be in communication with a space that is at the inner side of the upper cover 202 and yet at the outer side of the reservoir 209.
For example, the upper cover 202, shown in FIGS. 13 and 14, is provided with a small hole at a position that overlaps with the reservoir 209 in plan view.
This small hole may be provided instead at a position of the lower cover 203 that overlaps in plan view with the reservoir 209.
The reservoir 209 may be configured so that the outer shape of the reservoir 209 hardly changes when the drug solution is fed in the above-described manner via the liquid injection port 208 and when the drug solution is discharged by the micropump 212.
In this case, a material that does not readily deform elastically is selected as the material of the reservoir 209.
This invention is not limited to the above-described embodiments, and modifications, improvements, etc., within a range in which the objects of this invention can be achieved (within a range that does not deviate from the gist of the invention) are included in this invention.
That is, though this invention is illustrated and described in particular in regard to specific embodiments, a person skilled in the art can add various modifications, regarding the shape, material, combination, and other detailed arrangements and processing methods among manufacturing processes, to the above-described embodiments without deviating from the philosophy of the art and the scope of the objects of this invention.
The above-disclosed descriptions that limit the shape, material, manufacturing process, etc., are provided as examples for facilitating the understanding of this invention and because these do not limit this invention, descriptions using names of members, with which a part or all of the restrictions concerning the shape, material, and combination, have been eliminated, are included within this invention.
For example, though each of the above-described embodiments is described as a fluid transportation device to be implanted inside a living body, implantation is not limited to inside a living body and implantation in another equipment or device is also possible.
In particular, because the present fluid transportation device has a sealed structure, it is favorable as a fluid transportation device to be used inside a fluid or a location with much dust.
Thus, each of the above-described embodiments can provide a fluid transportation device, with which compactness and thinness are realized and which has a waterproof property enabling implantation inside a living body, enables additional injection of a drug solution to be performed at any suitable timing, enables continuous, sustained flow of a drug solution or other fluid of a microvolume, and is high in safety.
Though each of the above-described embodiments is formed in an outer shape that is substantially rectangular in plan view, this invention is not restricted thereto, and the outer shape may be square, circular, elliptical, oval, or semicircular in plan view and may even be spherical, etc.
Which outer shape is applied is selected according to the location, circumstances, etc., of use and, for example, with a type that is implanted under the skin, an outer shape that does not inflict discomfort (does not have an impact) upon implantation is selected.

INDUSTRIAL APPLICABILITY

Because the fluid transportation device according to this invention can be made compact and enables continuous flow at a micro flow rate with stability, it is favorable for implantation in a living body for development of a new drug, treatment, or other medical purpose.
The fluid transportation device according to this invention can also be used with various machines and devices and can be implanted inside a device or outside a device to transport water, saline solution, drug solution, oil, aromatic liquid, ink, gas, or other fluid.
The fluid transportation device according to this invention can also be used alone to feed or make an abovementioned fluid flow.
The drug solution feeder 201 or 301 according to this invention can be implanted, as described above, under the skin of an experimental animal and used in an animal experiment concerning a drug solution.
The drug solution may be for development of a new medical drug, for development of a nutrient agent for a small animal, etc., and the application thereof is not limited.
The drug solution feeder 201 or 301 according to this invention is not limited to being a device to be implanted in an experimental animal and may be applied to an application of implantation under the skin of a human body, and the drug solution in this case may be a drug solution for medical treatment or a nutrient solution and may be injected into a blood vessel or a muscle.

Claims

1. A fluid transportation device comprising:

an outer case constituted from an upper cover and a lower cover, having a sealed space;

a tube having elasticity;

a fluid transport mechanism, having a plurality of fingers that occlude the tube and a cam that successively presses the plurality of fingers from an inlet portion to an outlet portion, making a fluid flow continuously by squeezing the tube;

a driving force transmission mechanism disposed so as to be overlapped with the fluid transport mechanism, transmitting a driving force to the fluid transport mechanism;

a reservoir disposed at a position at which it does not overlap with the fluid transport mechanism and the driving force transmission mechanism, being in communication with the inlet portion of the tube, and containing the fluid;

a port injecting the fluid into the reservoir; and

an electric power supply supplying electric power to the driving force transmission mechanism, wherein

at least the fluid transport mechanism, the driving force transmission mechanism, and the electric power supply are housed in the sealed space of the outer case.

2. The fluid transportation device according to claim 1, wherein

the reservoir is housed in the sealed space of the outer case.

3. The fluid transportation device according to claim 1, wherein

the reservoir is held at an outer side of the outer case and inclines with respect to a surface of the outer case.

4. The fluid transportation device according to claim 1, further comprising:

a reservoir frame disposed on the outer side of the outer case, wherein the reservoir is detachably mounted via the reservoir frame.

5. The fluid transportation device according to claim 1, wherein

the driving force transmission mechanism includes: a step motor; and a watch movement, which in turn includes a wheel train having an hour wheel that protrudes in the direction of the fluid transport mechanism, and

the cam is insertingly attached to an axial portion of the hour wheel.

6. The fluid transportation device according to claim 1, wherein

the port is disposed so as to penetrate through the upper cover.

7. The fluid transportation device according to claim 1, further comprising:

a fluid flow inlet provided at the reservoir and being in communication with the tube; and

a fluid injection inlet, being in communication with the port, wherein

the fluid flow inlet and the fluid injection inlet are disposed at separated positions so that the fluid flows in the interior of the reservoir.

8. The fluid transportation device according to claim 1, wherein

the reservoir is formed of a deformable pouch.

9. The fluid transportation device according to claim 1, further comprising:

a fluid injection plug provided on the port and being formed of a material with elasticity, wherein

when a syringe-needle-like injection needle is inserted into the fluid injection plug to inject a fluid into the interior of the reservoir and the injection needle is thereafter extracted, the portion at which the injection needle was inserted becomes sealed by the elasticity of the fluid injection plug itself.

10. A fluid transportation device used for implantation under skin, the fluid transportation device comprising:

an outer case having a skin side surface and a rear surface, the skin side surface facing the skin when the fluid transportation device is implanted under the skin;

a port disposed at the skin side surface, having an injection opening which is exposed to the exterior of the outer case and enables injection of a fluid from the exterior;

a reservoir storing the fluid injected from the port;

a fluid conducting portion communicated with the reservoir, to allow the fluid to be conducted;

a micropump feeding the fluid to the exterior via the fluid conducting portion; and

a battery supplying power to the micropump.

11. The fluid transportation device according to claim 10, wherein

the reservoir and the micropump are separately disposed each other in plan view, and the port is disposed between the reservoir and the micropump in plan view.

12. The fluid transportation device according to claim 10, wherein

the port has a protrusion formed to protrude from the outer case, and the injection opening is formed in the protrusion.

13. The fluid transportation device according to claim 10, wherein

the battery is disposed so as to be overlapped with the reservoir in plan view and is disposed opposite the port across the reservoir in cross-sectional view.

14. The fluid transportation device according to claim 10, wherein

the port is disposed at a position so as not to overlap the battery in plan view.

15. The fluid transportation device according to claim 10, further comprising:

an IC controlling operations of the micropump;

a circuit substrate on which the IC is packaged; and

a signal supplying port disposed so as to be exposed from the outer case to enable a control program for controlling the operations of the micropump to be supplied to the IC.

16. The fluid transportation device according to claim 10, further comprising:

an attachment portion formed on the outer case in order to attach to a subject.

17. The fluid transportation device according to claim 10, wherein

the outer case has inclined surfaces at least at a portion of outer walls extending from the skin side surface to the rear surface.

18. The fluid transportation device according to claim 17, wherein

the outer case has vertical hold surfaces on outer walls extending from the skin side surface to the rear surface.

19. The fluid transportation device according to claim 17, wherein

the outer case includes: a first-narrow-side outer wall formed along a narrow-width direction at a first end of a wide-width direction; and a second-narrow-side outer wall formed along the narrow-width direction at a second end of the wide-width direction, and

the inclined surfaces are formed incliningly so that the first-narrow-side outer wall and the second-narrow-side outer wall converge from the rear surface toward the skin side surface of the outer case.

20. The fluid transportation device according to claim 17, wherein

the outer case includes: a first-wide-side outer wall formed along a wide-width direction at a first end of a narrow-width direction; and a second-wide-side outer wall formed along the wide-width direction at a second end of the narrow-width direction, and

the inclined surfaces are formed incliningly so that the first-wide-side outer wall and the second-wide-side outer wall converge from the rear surface toward the skin side surface of the outer case.