US3779082A

US3779082A - Aseptic sample fitting

Info

Publication number: US3779082A
Application number: US00295042A
Authority: US
Inventors: E Galloway
Original assignee: Galloway Co
Current assignee: Galloway Co
Priority date: 1972-10-04
Filing date: 1972-10-04
Publication date: 1973-12-18
Anticipated expiration: 1990-12-18
Also published as: CA975401A

Abstract

An aseptic sample fitting for a fluid enclosure includes a disposable tapered plug removably held in a neck with its inner end substantially flush with the enclosure interior. The plug includes a rigid core that is provided with circumferentially arrayed convergent sampling needle guide channels, and a cupshaped self-healing pressure seal member. A sanitary seal member of flexible sheet material protects the outer ends of the guide channels and also indicates the location and used or unused state of each channel. The inner end of the neck opening defines a feathered shroud which extends across a rounded edge of the plug to minimize exposed area and improve surface configuration. Barrier ridges surround each guide channel at the interface of the core and pressure seal member to prevent movement of material from one channel to another. A retainer ring bears against a holding flange on the core to hold the plug in place.

Description

[ Dec. 18, 1973 [57] ABSTRACT An aseptic sample fitting for a fluid enclosure includes a disposable tapered plug removably held in a neck with its inner end substantially flush with the enclosure interior. The plug includes a rigid core that is provided with circumferentially arrayed convergent sampling needle guide channels, and a cup-shaped self-healing pressure seal member. A sanitary seal member of flexible sheet material protects the outer ends of the guide channels and also indicates the location and used or unused state of each channel. The inner end of the neck opening defines a feathered shroud which extends across a rounded edge of the plug to minimize exposed area and improve surface configuration. Barrier ridges surround each guide channel at the interface of the core and pressure seal member to prevent movement of material from one channel to another. A retainer ring bears against a holding flange on the core to hold the plug in place.

11 Claims, 3 Drawing Figures ASEPTIC SAMPLE FITTING Inventor: Edwin J. Galloway, Menasha, Wis.

Assignee: Galloway Company, Neenah, Wis.

Filed: Oct. 4, 1972 Appl. No.: 295,042

73/421 B, 73/422 R Int. Cl. GOln l/l2 Field of Search............... 73/421 B, 425, 425.6, 73/422 GC; 138/89, 90; 141/329 References Cited UNITED STATES PATENTS United States Patent Galloway Primary Examiner-S. Clement Swisher AtmrneyAllan W. Leiser et al.

ASEPTIC SAMPLE FITTING BACKGROUND OF THE INVENTION This invention relates to a sample fitting for a fluid tank, line, or other enclosure; and is particularly intended for but not limited to processing, storage and/or delivery systems for food products that are susceptible to bacterial infection. One such system is shown in U.S. Pat. No. 3,371,822, issued Mar. 5, 1968.

It is highly desirable in any system where bacterial infection is a problem to be able to take samples at precise points to determine whether there has been an infection and, if there has, to be able to tightly bracket the point in the system where it has occurred. In many situations, it is necessary or desirable to take a timed series of samples, and in such cases it is very important that each sample be taken at a completely virgin location to avoid false readings based on residual infection from prior samplings.

The invention contemplates the use of a pierceable, self-healing seal member which allows for the insertion of a hypodermic needle or similar instrument for the purpose of taking a sample. This principle is not new as such, having been used for example in closures for medicine containers, but previously known arrangements are not fully satisfactory for the purposes now contemplated. For one thing, ice cream mixes and other food products may be subject to extremely rapid bacterial infection, and it is highly important to avoid arrangements which present projections or pockets that could trap fluid and allow it to accommodate bacterial growth. Also, it is often necessary in commercial applications to work against rather high pressures, for example about 150 p.s.i., and prior seals are not secure enough. As previously indicated, where a series of samples is desired it is very important to provide a virgin location for each, and conventional medicine closures where a needle pierces a membrane at random do not guarantee a new location for each insertion.

SUMMARY OF THE INVENTION It is the general object of this invention to provide a highly effective, versatile, pierceable sample fitting that is asceptic in the sense that it does not contribute to bacterial infection of the system and prevents residual infection from interfering with the sampling process where a series of samples are taken.

One particular object of the invention is to provide a fitting that may readily be incorporated into a fluid tank, a line fitting, or any other kind of fluid receptacle or enclosure. Another object is to provide a fitting which gives a highly effective seal even in the face of relatively high fluid pressures. Still another object is to provide a fitting with a plug that has a rigid core for strength and in which the core defines guide channels that provide support for a sampling needle and guide the needle to assure sampling at a virginlocation at the product interface. A further object is to provide a fitting in which there are several'guide channels which are convergent to minimize the target area at the product interface while providing greater spacing at the outer ends. Still another object is to provide a fitting in which there is a flexible disc which seals off and protects the channels, clearly defines the unused channels and makes obvious which ones have been used. A still further object is to provide a fitting which is relatively simple and inexpensive, and allows for the use of a disposable plug. Still another object is to provide a fitting in which the inner end of the plug is substantially flush with the interior of the fluid enclosure so that there are no substantial pockets or projections which might trap fluid and thus increase the possibility of infection. A still further object is to provide a fitting in which the interface between the core and sealing member is shaped to define barrier ridges around each guide channel to prevent material, and bacteria, from moving from one channel to the other. Still another object is to provide a fitting in which a neck portion is shaped to define a feathered shroud which extends across the inner edge of the plug to limit the area of the plug which is exposed to pressure, the shroud also serving to help provide a flush surface with a slight crowning of the inner end of the plug which gives a desirable wiping action. Still other specific features, objects and advantages will appear from the description to follow.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial side view, with parts shown broken away and in cross section, of an elbow for a fluid line that incorporates a sample fitting constituting a preferred embodiment of the invention,

FIG. 2 is a top plan view, partially broken away, of the fitting of FIG. 1, and

FIG. 3 is an enlarged view in cross section through the plane 33 shown in FIG. 11.

DESCRIPTION OF THE PREFERRED EMBODIMENT The preferred embodiment of the invention shown and described herein is incorporated in a conventional elbow fitting l which defines a through passage 2 of circular cross section and is provided with usual end connectors (not shown). While it is particularly convenient to incorporate a sample fitting in such an elbow, the same type of fitting may be incorporated in other line fittings or incorporated in or attached to a fluid tank or other receptacle. The fitting of the invention is suitable for use in connection with any type of enclosure which retains or transmits fluid.

The sample fitting proper comprises a neck 3 that, in the preferred embodiment, is welded to and extends outwardly from the enclosure l and is provided with external sanitary threads 4. The neck 3 defines an opening 5 of substantial axial length that leads to the interior 2 of the enclosure l, the opening 5 being of circular cross section and inwardly axially tapered so as to be smaller at its inner end, the end which communicates with the passage 2. An equivalent neck might of course be formed integrally with an enclosure, or where the enclosure wall is thick enough it might be formed entirely in the wall.

The sample fitting also includes a plug designated generally by the reference numeral 6. The inner end portion of the plug 6 is tapered to conform with the opening 5, and the plug 6 is removably received in the opening 5 with its inner end surface 7 substantially flush with the interior passage 2. There may be some variance if, for example, the surface 7 is substantially flat and is used with a passage of circular cross section like the passage 2, and it is desirable to provide for a slight crowning as will be described, but it is important that the surface '7 be substantially flush with the interior of the enclosure with which the sample fitting is used to minimize pockets or projections which might trap fluid.

The plug 6 is made up of two parts, a rigid internal core 8 which is preferably formed of a molded plastic material such as nylon or Teflon and a cup-shaped external pressure seal member 9 which is formed of a natural of synthetic rubber or any other material that is compressible, pierceable by a hypodermic needle or similar sampling device, self-healing after withdrawal of the needle, and chemically inert with regard to the fluid involved. The core 8 has a reduced, tapered inner end 10 which extends into the opening but is substantially spaced from the sides and inner end thereof; and the open end of the pressure seal member 9 receives the end and is adhesively or otherwise tightly bonded thereto. If desired, the inner end 10 can be provided with exterior ridges or serrations to improve the bond.

The core 8 defines an outwardly extending annular holding flange 11 above the pressure seal member 9, which extends across and bears against the outer end of the neck 3. A retainer in the form of a ring 12 is removably threaded on the neck threads 4, and is provided with an inwardly extending annular retainer flange 13 which extends over and bears against the flange 11, the retainer 12 thus serving to removably hold the plug 6 in place in the opening 5. The tapered configuration of the opening 5 and plug 6 helps insure a secure seal, and the dimensions of the parts are such that the pressure seal member 9 is in compression when the plug 6 is in place. The side portions of the pressure seal member 9 then sealingly engage the sides of the opening 5, and the inner or closed end of the member 9 defines the inner end surface 7 The edge of the pressure seal member 9 surrounding the inner end surface 7 is rounded at 14, and the inner end of the opening 5 is shaped to define a feathered shroud 15 which mates with and extends across the rounded edge 14. The shroud 15 provides additional support when the member 9 is under compression to help in providing a more effective seal, and also serves to mask any flash that might be developed in the molding of the member 9. The shroud 15 also defines a minimum area of exposure to pressure for the inner end surface 7, which also enhances the seal. When the member 9 is under compression, it tends to crown slightly in the area circumscribed by the shroud 15, and the slightly crowned portion which extends into the passage 2 causes a desirable wiping action as fluid moves therethrough, without developing substantial pockets or projections which would trap fluid.

The core 8 is provided with a plurality six in the preferred embodiment of needle guide channels 16 which are circumferentially arrayed or spaced around its longitudinal axis and which extend axially through the core 8. These guide and support a hypodermic needle (not shown) or similar sampling device inserted through the outer end of the core 8 for purposes of taking a sample. It will be understood that the needle can pierce the inner end of the pressure seal member 9 so that a sample can be taken from the passage 2, but that the material of the member 9 is self-healing so that upon withdrawal of the needle there will be no substantial escape of fluid. The fact that there are a plurality of channels 16 means that a series of samples can be taken using a new or virgin channel 16 for each sample and thus eliminating the risk of residual infection which could cause false readings.

The channels 16 are generally conical, with their radially innermost longitudinal edges parallel to the longitudinal axis of the core 8 and their radially outermost edges converging toward the center or longitudinal axis at the inner end of the core 8. This convergence of the axes of the channels 116 makes possible the achievement of a relatively small target area at the product interface which is highly advantageous. For one thing, it maximizes the internal pressure which can be accommodated by a given retainer system. Secondly, because the properties of materials providing the self-healing characteristics of the pressure seal are antithetic to those which provide optimum sanitation, it is desirable to keep the target interface area as small as possible. The outer ends of the channel 16 are larger and spread further apart which makes it easier for the operator to insure that a needle is inserted into the proper channel and provides greater spacing between the outer ends of the channels to minimize the possibility that material will travel between them. Convergence could be provided by using straight-sided or stepped channels arranged in convergent fashion, but the conical configuration shown provides the desired convergence with a configuration that lends itself to conventional molding techniques.

The inner end of the core 8 is shaped to define a relatively long and thick peripheral skirt 17 which provides additional support for the pressure seal members 9. In addition, and as can be seen most clearly in FIG. 3, the inner end of the core 8 defines a group of upstanding ridges 18 which surround the inner ends of the channels l6 and which are covered by the material of the member 9. The ridges l8 and skirt 17 together define upstanding barrier ridges which surround the inner ends of each channel 16 to minimize the possibility of material traveling across the interface between the core 8 and pressure seal member 9, particularly when the fitting is being used in a high pressure application. If desired, the same effect could be provided by using grooves in the inner end of core 8 into which the material of the member 9 would extend, or other suitable arrangements could be used at the interface of the core 8 and member 9.

A circle or disc 19 of vinyl tape is adhesively secured to the outer end of the core 8 and covers the outer ends of the channel 16 to serve as a sanitary seal which prevents contamination of the channels 16 until they are used. Vinyl tape is preferred, but might be replaced by any material which is suitably flexible and pierceable and which is bacteriologically impervious. The tape disc 19 is preferably applied when the core 8 is warm, so that upon cooling it will be drawn slightly into the outer ends of the channels 116 to develop dimples or depressions 19! which make it even easier for the operator to determine the location of each channel 116. In addition, after a needle is inserted through the tape 19 there will be a break, which will indicate clearly to the operator whether a particular channel 16 has been used.

The core 8 is preferably provided with a centrally located threaded bore or pull out opening 20 which can receive a suitable tool to help in removing the plug 6 from the opening 5 after use.

The plug 6 is intended to be disposable and is supplied presterilized in a suitable sterilized protective container. The plug 6 is usually replaced when the system is ready to be sterilized for a new cycle, and the preferred procedure is to remove the used plug, clean the opening 5 and insert a new plug and sterilize it with the system. Once the plug is in place, the operator can take six successivesamples, with assurance that each will be taken through a completely sterilized, virgin passage as a further guarantee it is desirable to wipe the disc 19 with alcohol or another suitable sterilizing agent immediately prior to each sampling. The features noted above cooperate to prevent contamination of any channel 16 because of a previous sampling through another channel. In addition, the plug 6 provides a highly effective seal for the opening 5, even in the face of relatively high pressures. The composite construction of the plug 6 is important in this regard, the core 8 providing necessary rigidity and strength while the pressure seal member provides a secure seal with the opening 5 and a self-healing barrier for insertion of sampling needles. The plug 6 may easily be made of relatively inexpensive materials so as to be disposable.

While a preferred form of the invention exhibiting all of the advantages and features referred to above has been shown and described, various modifications might be made without departure from the spirit of the invention. The invention is not intended to be limited by the showing or description herein, or in any other manner, except insofar as may specifically be required.

I claim:

1. A sample fitting for a fluid enclosure, said fitting comprising: a neck that defines an opening of substantial axial length that leads to the interior of the enclosure and that is axially tapered to be smaller at its inner end; a tapered plug removably received in the opening with a close fit and with its inner end substantially flush with the enclosure interior, the plug including a rigid internal core having an inner end that extends into and is substantially spaced from the sides and inner end of the opening and that is provided with at least one needle guide channel extending axially therethrough, the plug also including an external cup-shaped pressure seal member of a compressible, pierceable, self-healing material that receives and is tightly secured to the inner end of the core and that sealingly engages the sides of the opening and defines the inner end surface of the plug; and a releasable retainer to hold the plug in the opening.

2. A sample fitting according to claim 1, wherein: the neck extends outwardly from the enclosure and is ex ternally threaded; and the core defines an outwardly extending annular holding flange that extends over and bears against the outer end of the neck; and the retainer comprises a ring removably threaded on the neck that has an inwardly extending annular retainer flange that overhangs and bears agains the holding flange.

3. A sample fitting according to claim ll, wherein: the core is provided with a plurality of separate needle guide channels extending axially therethrough.

4,. A sample fitting according to claim 3, wherein: there is a sanitary seal member of flexible, pierceable sheet material covering the outer ends of the needle guide channels.

5. A sample fitting according to claim 3, wherein: the interface between the inner end surface of the core and the pressure seal member is shaped to define upstanding barriers surrounding the inner end of the needle guide channels.

6. A sample fitting according to claim 3, wherein: the needle guide channels are circumferentially arrayed and are conical with radially innermost edges that are parallel to the longitudinal axis of the core and radially outermost edges that converge toward the center of the inner end of the core.

7. A sample fitting according to claim 6, wherein: the edge surrounding the inner end surface of the plug is rounded; and the inner end of the opening is shaped to define an annular feathered shroud that mates with and extends across the rounded edge.

8. A sample fitting according to claim 7, wherein: there is a sanitary seal member of flexible, pierceable sheet material covering the outer ends of the needle guide channels.

9. A sample fitting according to claim 8, wherein: the interface between the inner end surface of the core and the pressure seal member is shaped to define upstand ing barriers surrounding the inner ends of the needle guide channels.

110. A sample fitting according; to claim 9, wherein: the neck extends outwardly from the enclosure and is externally threaded; and the core: defines an outwardly extending annular holding flange that extends over and bears against the outer end of the neck; and the retainer comprises a ring removably threaded on the neck that has an inwardly extending annular retainer flange that overhangs and bears against the holding flange.

11. A sample fitting according to claim Ml, wherein: the core is provided with a centrally located, outwardly M050 UNITED STATES PATENT @FFTCE CERTTTICATE @F CQRREQTTQN Patent No, 3, 779, 082 Dated December 18, 1973 Inventor(s) Edwin J. Galloway It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

I" "I 7 Column 3, line 7, "of" should read or Column 6, line 1 "agains" should read against Column 6, line 16 "end" should read ends Signsd and sealed this 23rd day of April 19m.

(SEAL) Attest:

EDWARD l-LFLMTUHIJH yJiio C a MARSHALL DANN Attesting Officer Commissioner of Patents

Claims

2. A sample fitting according to claim 1, wherein: the neck extends outwardly from the enclosure and is externally threaded; and the core defines an outwardly extending annular holding flange that extends over and bears against the outer end of the neck; and the retainer comprises a ring removably threaded on the neck that has an inwardly extending annular retainer flange that overhangs and bears agains the holding flange.

3. A sample fitting according to claim 1, wherein: the core is provided with a plurality of separate needle guide channels extending axially therethrough.

4. A sample fitting according to claim 3, wherein: there is a sanitary seal member of flexible, pierceable sheet material covering the outer ends of the needle guide channels.

9. A sample fitting according to claim 8, wherein: the interface between the inner end surface of the core and the pressure seal member is shaped to define upstanding barriers surrounding the inner ends of the needle guide channels.

10. A sample fitting according to claim 9, wherein: the neck extends outwardly from the enclosure and is externally threaded; and the core defines an outwardly extending annular holding flange that extends over and bears against the outer end of the neck; and the retainer comprises a ring removably threaded on the neck that has an inwardly extending annular retainer flange that overhangs and bears against the holding flange.

11. A sample fitting according to claim 10, wherein: the core is provided with a centrally located, outwardly opening threadEd pullout bore.