US3195806A

US3195806A - Pumps for fluids

Info

Publication number: US3195806A
Application number: US284538A
Authority: US
Inventors: John C Bowen; Robert C Wolf
Original assignee: PRESSURE PRODUCTS IND Inc
Current assignee: PRESSURE PRODUCTS IND Inc
Priority date: 1963-05-31
Filing date: 1963-05-31
Publication date: 1965-07-20
Anticipated expiration: 1982-07-20

Description

y 20, 1965 J. c. BOWEN ETAL 3,195,806

PUMPS FOR FLUIDS Filed May 31. 1963 INVENTORS JOHN C. BOWEN ATTORNEY United States Patent 3,195,806 PUMPS FOR FLUIDS John C. Bowen, Davisville, and Robert C. Wolf, Hatboro,

Pa., assignors to Pressure Products Industries, Inc., Hatboro, Pa., a corporation of Pennsylvania Filed May 31, 1963, Ser. No. 284,538 7 Claims. (Cl. 230-69) This invention relates to pumps for fluids and more particularly to pumps for the delivery of small quantities of gas at very high pressures.

Compressors for delivering gas at very high pressures, and employing diaphragms and pistons, are currently in use but no apparatus is available for the delivery of small quantities of a specific gas at very high pressures.

It is the principal object of the present invention to provide a pump for fluids in which the pumping action is effected by expansion of the fluid by heating the fluid in a chamber.

It is a further object of the present invention to provide a pump in which the pumping action is effected by heating the fluid in a chamber which chamber serves as a resistance heating element.

It is a further object of the present invention to provide a pump for fluids which is simple in construction, free from operating difliculties, and with which small quantities of a specific gas at high pressure can be easily obtained.

It is a further object of the present invention to provide a pump of the character aforesaid in which the pumping space comprises an intermittently heated capillary tube.

It is a further object of the present invention to provide a pump for delivery of small quantities of gas at very high pressures in which the pumping space comprises a capillary tube which is quickly heated and cooled in a continuous cycle.

It is a further object of the present invention to provide a pump for delivery of small quantities of gas at very high pressures in which the pumping space comprises a capillary tube and the tube serves as a resistance heating element for heating the fluid therein.

Other objects and advantageous features of the invention will be apparent from the description and claims.

The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawing forming part thereof, in which:

The figure is a diagrammatic view illustrating the pump in accordance with the invention.

It should, of course, be understood that the description and drawing herein is illustrative merely and that various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention.

In accordance with the invention gas of any desired type or kind, and from any suitable source, is delivered through an inlet check valve to a heating vessel which serves as a pumping chamber, and from the heating vessel is delivered through a delivery check valve to the high pressure gas receiver. The heating vessel is alternately heated and cooled. For purposes of heating the vessel advantageously serves as an electrical resistance heater. For purposes of cooling air or other cooling fluid may be circulated over the exterior of the heating vessel.

Referring now more particularly to the drawing, a source 10 of gas to be delivered is illustrated which can be a gas tank or other receptacle of gas previously compressed to a predetermined level. The gas at the source may be nitrogen, hydrogen, air, or other gas to be compressed.

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The source 10 of gas is connected by a pipe 11 to an inlet check valve 12 of any preferred type capable of operation at very high pressures. The check valve 12 is connected to the heating vessel 15. The heating vessel 15 is connected to a delivery check valve 16 which in turn is connected by a pipe 17 to the high pressure gas receiver 18. The

check valves

12 and 16 and the connections to the heating vessel 15 can be mounted within a suitable housing 19.

The heating vessel 15 which provides the pumping chamber is preferably of capillary tubing capable of serving as an electrical conductor and resistance heater, and in a specific embodiment of the invention, capillary tubing of a length of about one hundred feet in an open coil sealed at one end, gave satisfactory results.

In order to provide the energy input to heat the vessel 15, one end of the capillary tubing is connected by a conductor 20 to a switch contact 21, the other end of the capillary tubing being connected by a conductor 22 to ground.

A source 23 of electrical energy is connected to ground by a conductor 24 and by a conductor 25 to a switch arm 26.

An electric motor driven fan 30 is provided having a conductor 31 extending to ground and a conductor 32 extending to a switch contact 33 for selective engagement by the switch arm 26.

The fan 30 has a fan blade 34 for directing a stream of cooling fluid, such as atmospheric air, over the exterior of the heating vessel 15. A housing 35 can be provided to aid in directing the cooling fluid flow.

The source 23 of electrical energy can be connected as desired to the heating vessel 15 to heat the same by movement of the switch arm 26 to alternately engage the contacts 21 and 33. This movement of the switch arm 25 can be effected in any desired manner such as by a variable or adjustable motor driven timer 36.

The mode of operation will now be pointed out.

Assuming a sufiicient pressure of fluid at the source 10, the fluid is delivered to fill the pipe 11, the heating vessel 15, the pipe 17 and the receiver 18.

If now, heat is applied to the heating vessel 15, expansion of the fluid in the heating vessel 15 occurs and part of the fluid is delivered past the delivery check valve 16 and through the pipe 17 to the gas receiver 18.

Heating of the vessel 15 is effected upon engagement of the switch arm 26 with the contact 21 and the resistance heating by the current applied on the capillary tube employed for the vessel 15.

Upon completion of the heating, the current supply to the vessel 15 is interrupted by separation of the switch arm 26 from the switch contact 21.

While the vessel 15 might be permitted to cool without outside assistance, it is preferred, in the interest of more rapid operation, to employ the motor driven fan 30 to apply a positive flow of cooling fluid on the exterior of the vessel 15. Upon separation of the switch arm 15 from the switch contact 21 it is accordingly preferred to move the switch arm 26 to engage the switch contact 33 to actuate the fan 30 and its fan blade 34.

Upon cooling of the heating vessel 15, additional fluid from the source 10, delivered through the pipe 11 will pass the check valve 12 and refill the heating vessel 15.

The heating cycle can then be repeated.

The operation of the pump heretofore described for gases is dependent upon the gas laws and the temperature relation:

where T is the initial or input gas temperature in abt s a a J v solute temperature units and T is the outputgas temperature expressed in the same units.

It will be seen that doubling or tripling of thetemperature difference can be readily effected within practicable operating ranges: Forfexample, heating the gas irithe 7 means inclu ding electric current applying members connected to said'chamber'at spaced locations for heating said chamber for selected time intervals, and means for V cooling said chamber for selected time intervals intervessel 15 to a temperature of theorder of 600 F. (1060 v V F. abs.) has been foundsatisfactory' fora'specific opera 1 tion.

The apparatus 'of'the' present invention has been found to be suitable for elfecting deliveryof 'small quantities of gas at exceedingly high pressures which may range up to 50,000 to 100,000 p.s.i. I We claim:

' 1. A pump for fluidsEcomprising a"connecti'on to a source of fluid, an inlet valve member connected to said connection,:a fluid" chambericonnected to said valve meme her and having a wall of electrical conductive material, a delivery valve'member connected to said fluidcch'am posed between said heating time intervals.

6. A pump for; fluids comprisinga connection to a seurce of-fluid, a fluid delivery connection, a fluid chamber'connected to said connections, said fluid chamber comprising an electrically conductive capillarytube, inlet and delivery valve members in said connections, means for heating said chamber for selected time intervals said b means for heating including electric current applying members connected to said capillary tube, and means for cool- ,in'g said ch'amber for selected time intervals interposed between said heatingtime intervals.

17- A pump for fluids comprising a" connection to a 7 source of'fluid, a fluid delivery. connection',; a fluid chamber connected to saidconnections andcomprising an elecber, and means fort intermittently heating, said'qchamber a for expansion of fluid therein and delivery of'fluidthrough the delivery valve member, said'means including a source of electrical energy and, connections :to spaced portions r of saidwallforapplying current thereto from said source 7 for heating said wall. a I 1 I 2. A pump for fluidsas defined in claim l'fin which said chamber isa capillary tubef v 3. A pump for fluids as defined in claim 1 in which said chamber is a coiledcapillarytube.

4. A pump for fluidsas definedin claim 1 also having trically conductive capillaryrtube, iinlet and delivery valve members in said connections, means for heating said chamber forgselected timeiin'tervals including elec tric' current applying mem ers connected to said capillary tube, and means for cooling saidchamber for selected time intervals interposed betwen saidheatin'g timeintervalsincluding a motor driven device for delivering cooling fluid in'contact with saidftube.

means for intermittently cooling said chamber in intervals between current application for heating; 7 I

V 5. 'A pump for fluids comprising a connection to. a

source of fluid, a fluid deliveryconnection, tin-electrically conductive fluid chamber connected 7 to said connections,

inlet and delivery valve members in said. connections,

- References Cited'by-the Examiner v UNITED STATES PATENTS 1,630,943 'S/ZT'l-Iu'tton s 23069 2,510,427 6/50 S'ou'cie' 230-69

Claims

1. A PUMP OF FLUIDS COMPRISING A CONNECTION TO A SOURCE OF FLUID, AN INLET VALVE MEMMBER CONNECTED TO SAID CONNECTION, A FLUID CHAMBER CONNECTED TO SAID VALVE MEMBER AND HAVING A WALL OF ELECTRICAL CONDUCTIVE MATERIAL, A DELIVERY VALVE MEMBER CONNECTED TO SAID FLUID CHAMBER, AND MEANS FOR INTERMITTENTLY HEATING SAID CHAMBER FOR EXPANSION OF FLUID THEREIN AND DELIVERY OF FLUID THROUGH THE DELIVERY VALVE MEMBER, SAID MEANS INCLUDING A SOURCE OF ELECTRICAL ENERGY AND CONNECTIONS TO SPACED PORTIONS OF SAID WALL FOR APPLYING CURRENT THERETO FROM SAID SOURCE FOR HEATING SAID WALL.