US 3738776 A
The invention relates to a pumping device comprising a pump driven by a motor, a diaphragm which is subjected to the water pressure downstream of the pump and a contactor which is actuated by the diaphragm for the purpose of controlling the motor. The pump is of the gear type and a check-valve is placed upstream of the diaphragm in the distribution line which is supplied by the pump.
Description (OCR text may contain errors)
United States Patent 1 Debare PUMPING DEVICE, ESPECIALLY FOR WATER SUPPLY  Inventor:
 Assignee: Societe Francaise DEquipement Menagen, Lourdes, France 22 Filed: Aug. 2, 1971 21 App]. No.: 168,213
Jacques Debare, Tarbes, France  Foreign Application Priority Data Sept. 24, 1970 France 7034616  U.S. Cl. 417/38, 417/44  Int. Cl. F04b 49/02  Field of Search 417/44, 201, 310,
 References Cited UNITED STATES PATENTS 3,694,105 9/1972 Martin 417/44 2,123,651 7/1938 Gallagher.... 417/201 2,631,540 3/1953 Baugh 417/310 2,956,507 10/1960 Hutchinson 417/478 11] 3,738,776 1451 June 12,1973
3,120,814 2/1964 Mueller 417/310 3,380,468 4/1968 Falden 417/44 3,387,105 6/1968 Russell ZOO/81.4 3,446,238 5/1969 Norstrud 417/44 FOREIGN PATENTS OR APPLICATIONS 158,828 1/1940 Germany 417/199 Primary Examiner-William L. Freen Attorney-Irving S. Thompson and Robert J. Patch  ABSTRACT The invention relates to a pumping device comprising a pump driven by a motor, a diaphragm which is subjected to the water pressure downstream of the pump and a contactor which is actuated by the diaphragm for the purpose of controlling the motor. The pump is of the gear type and a check-valve is placed upstream of the diaphragm in the distribution line which is supplied by the pump.
The invention is of particular interest for the supply of water to caravans, bungalows or like premises.
2 Claims, 4 Drawing Figures PAIENIE JUN 1 ems PUMPING DEVICE, ESPECIALLY FOR WATER SUPPLY This invention relates to a pumping device, in particular for supplying water to a caravan, a bungalow or any other premises.
In known pumping devices of this type, an electric motor drives a pump and is started up, for example, by means of a pedal which must be located near the watersupply cock.
These devices call for the use of an electric cable of substantial cross-section which is therefore costly since the power supply is usually low voltage. The user is obliged to synchronize start-up of the motor and the movements of opening and closure of the cocks;-moreover, the user must press a pedal or like device after opening the cock.
It will also be noted that a control pedal as well as a separate electric cable must be associated with each cock and this constitutes a serious disadvantage both from economical and operational standpoints.
The aim of the invention is to overcome the many disadvantages referred-to and to provide a pumping device of simple, rugged and inexpensive constructional design which can be operated with a high degree of ease and convenience.
In accordance with the invention, the pumping device which is primarily designed to supply water to a caravan, a bungalow or other premises comprises a pump driven by a motor, a pressure-sensing element such as a diaphragm which is subjected to the water pressure downstream of the pump and a contactor actuated by the diaphragm for controlling the motor is characterized in that the pump is of the gear type and that a check-valve is placed upstream of the diaphragm in' the distribution line which is fed by the pump.
The use of a gear-type pump makes it possible to reduce the power consumption to a level such that disposable dry cells can be employed, thus permitting a substantial reduction in operating costs.
ACcording to one advantageous feature, the toothed wheels of the pump are housed in acavity of a pump body on which the motor is .fixed whilst the checkvalve, the diaphragm and the contactor are integrated .in the form of a unitary assembly which is connected to g the pump.
This integration of the different elements of the device limits the number of components and serves to reduce the overall size and weight of the complete assembly.
In a preferredembodiment, the pump body is constructed in one piece with a second body in which is formed a chamber, said chamber being closed by the diaphragm and adapted to communicate with a passageway which is connected to the pump and can be sealed-off by the check-valve.
The structure of the device is thus simplified to a remarkable degree and manufacture of the pump body is consequently facilitated.
Further particular features will become apparent from the following description, reference being had to the accompanying drawing which is given by way of example without any limitation being implied, and in which:
FIG. 1 is a general diagram of a pumping device in accordance with the invention;
FIG. 2 is a view in part-sectional elevation showing one industrial form of construction, this view being taken along line Il-II of FIG. 3;
FIG. 3 is a bottom view of the device of FIG. 2 after the base plate has been removed;
FIG. 4 is a part-sectional view taken along line IV-IV of FIG. 3 after the check-valve has been removed.
The pumping device which is shown diagrammatically in FIG. 1 comprises a pump 1 of the gear type which is driven by an electric motor 2 and connected by means of a water admission line 3 to a storage tank 4. There is mounted in the distribution line 5 which is fed by the pump a check-valve 6 followed by an assembly consisting of diaphragm 7 and contactor 8; the diaphragm which is subjected to the water pressure downstream of the pump actuates the contactor which in turn controls the operation of the motor. The distribution line terminates in either one or a number of cocks such as the cock 9. There is mounted in the admission line 3 upstream of the pump 1 a priming bulb 10 formed of flexible material such as rubber.
The operation of said pumping device takes place as follows:
Opening of the cock 9 causes a pressure drop within the distribution line 5 at the level of the diaphragm 7, with the result that the contactor is not actuated by the diaphragm and closes the electric circuit of the motor which is automatically started-up. The pump then comes into operation in order to feed the cock.
Conversely, at the time of closure of the cock 9, the water pressure which acts on the diaphragm increases, the check-valve is closed and this makes it possible to stabilize the pressure within the distribution line 5. Above a predetermined value of pressure, the diaphragm actuates the contactor, thereby stopping the motor and consequently the pump until the cock is reopened. v
The bulb 10 serves to prime the pump both rapidly and easily; when the bulb is compressed, the air within the line 3 is driven through the water of the tank 4; when the bulb is released, the water penetrates into the line and reaches the pump.
Reference will now be made to FIGS. 2 to 4 which illustrate one example of industrial construction which is specifically designed for supplying water to a caravan or a bungalow.
The gear pump 1 is housed within a cavity 12 of a pump body 11 which is preferably formed of molded plastic material such as an acetal resin. The electric motor 2 which is of conventional type and operates for example at a voltage of 12 volts and a speed of 4,000
rpm is fixed on the pump body 11; the rotor 13 of said motor is fitted with a shaft 14 which is rotatably mounted within a bore of the pump body and within the cavity 12 after having passed through a seal 15 of rubber, for example. Said shaft carries one of the toothed wheels 16 of the gear pump whilst the other wheel 17 is freely mounted on a pin 18 which is fixed within the pump body 11.
The cavity 12 is formed by two cylindrical molded recesses in which the toothed wheels l6, l7 rotate with minimum play. There have also been formed within the body 11 at the time of molding a passageway 19 for the admission of water which opens into the cavity 12 and a passageway 20 for the discharge of water which extends from the cavity on the opposite side.
The pump body 11 is formed in one piece with a second body 21 in which is formed a chamber 22, said chamber being closed by the diaphragm 7 and capable of communicating with a cavity 23 into which opens the discharge passageway 20 (as shown in particular in FIG. 3) and which can be sealed-off by the valve. The check-valve 6 whose seat 24 is formed by the body 21 is mounted within the chamber 22, the restoring spring 25 of the valve being attached to a perforated plate 26 which is placed beneath the diaphragm 7. Said diaphragm is constituted, for example, by a sheet of rubber which is fixed in position on the body 21 by means of a cover 27. The cover encloses the contactor 8 and a push-rod 28 which is applied against the diaphragm 7 and urged towards this latter by a restoring spring 29.
A duct 30 which forms part of the admission line 3 and is molded in one piece with the pump body 11 opens into the passageway 19. The priming bulb (which is not shown in FIG. 2) is mounted between said duct and, for example, a flexible hose which terminates in the storage tank 4.
Similarly, the chamber 22 communicates with a discharge duct 31 which forms part of the distribution line 5 and is molded in one piece with the body 21; for example, said duct is extended by a flexible hose which leads to the cock 9.
The contactor8 is constituted by a flexible-strip device of known type comprising a strip 32 which is attached to the cover 27 and curved downwards in order to permit engagement with the push-rod 28 and an element 33 which is connected on one side to the strip 32 and on the other side to a strip 34 which carries a movable contact-stud 35 and this latter cooperates with either of two stationary contact-studs 36 and 36a. The contact-studs 35, 36 form part of the electric circuit of the motor 2 and the contact made between said studs initiates closure of the circuit and therefore the supply of current to the motor.
The two bodies 11, 21 are fixed on a stainless steel base plate 37 which forms the bottom of the cavity 12, of the passageways 19, and the ducts 30, 31. A toric seal 38 which is placed within a groove formed in the bodies 1 1, 21 so as to surround all the cavities or openings ensures leak-tightness between the plate 37 and the bodies 1 l, 21. Attachment of said bodies is carried out by means of screws, for example, which are engaged in holes 39, 40, the holes 39 being also provided for the purpose of fixing the motor 2 on the body 11 and the holes 40 being provided in order to fix the cover 27 on the body 21.
It is apparent that, when the cock 9 is open, the check-valve 6 is displaced from its seat 24 under the action of the water pressure which is higher than the pressure of the spring 25; the water contained in the chamber 22 passes through the perforated plate 26 and exerts pressure on the diaphragm 7. However, the pushrod 28 is in the bottom position since the action of the spring 29 is preponderant, with the result that the contact-studs 35 and 36 are in contact with each other. The supply circuit of the motor 2 is then closed and the pump 1 operates normally so as to feed the cock.
As soon as the cock is closed, the pressure within the distribution line 5 increases and, at a predetermined value, the push-rod 28 is displaced upwards against the action of the spring 29 whilst the check-valve 6 is applied against its seat. The contact-studs 35 and 36 are then separated and the supply to the motor is cut off. It is only necessary to re-open the cock in order to ensure automatic re-starting of the motor by reason of the pressure drop within the chamber 22.
It will be noted that the construction of the pumping device which has been described in the foregoing calls for only a small number of inexpensive parts which are integrated in a compact assembly of small overall size. By reason of its low power consumption, the device can be supplied by means of disposable dry cells.
What we claim is:
1. A pumping device for liquid supply, comprising a gear pump, an electric motor driving said gear pump, a distribution system fed with liquid by said pump, said distribution system comprising a pressure-sensing diaphragm downstream of the pump and subjected to liquid pressure downstream of the pump, an electric contactor actuated by said pressure-sensing diaphragm to control said motor, and a single check valve located downstream of said pump and upstream of said pressure-sensing diaphragm, said check valve being mounted in a chamber of a first body which is integral with a body in which said gear pump is housed, said chamber being closed by said pressure-sensing diaphragm and communicating with a passageway which is connected to the pump and which is adapted to be closed by said check valve, said check valve having a restoring member which is secured to a perforated plate mounted adjacent the diaphragm.
2. A pumping device as claimed in claim 1, and a cover which maintains said diaphragm against the firstmentioned body, said cover containing said electric COl'ltflCtOI.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 3,738,776 a d June 12, 1973 Inventor-(s) Jacques Debare It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
On the cover'sheet  "Societe Francaise D'Equipement Menagen" should read Societe Francaise D'Equipement Menager Signed and sealed this 26th day of March 1974.
EDWARD M.FLETCHER,JR. C. MARSHALL DANN Attest'ing Officer Commissioner of Patents r -oRM PO-1050 (10439) USCOMM-DC 60376-1 69 a u.s. GOVERNMENT PRINTING OFFICE: I969 0-368-334.