US3357360A

US3357360A - Hydraulic pumping system

Info

Publication number: US3357360A
Application number: US509089A
Authority: US
Inventors: George L Borell
Original assignee: Purex Corp Ltd
Current assignee: Purex Corp Ltd
Priority date: 1965-11-22
Filing date: 1965-11-22
Publication date: 1967-12-12
Anticipated expiration: 1984-12-12

Description

Dec. 12, 1967 G- L. BORELL. 3,357,360

HYDRAULIC PUMPING SYSTEM Filed Nov. 22. 1965 [VVE/VTOR. GEORGE L. .B0/2ELL Arrow/5Y5.

United States Patent 3,357,360 HYDRAULIC PUMPING SYSTEM George L. Boreil, Anaheim, Calif., assignor to Purex Corporation, Ltd., Lakewood, Calif., a corporation of California Filed Nov. 22, 1965, Ser. No. 509,089 9 Claims. (Cl. 10344) ABSTRACT OF THE DISCLOSURE Hydraulic pumping means actuable by fluid pressure is provided including, typically, a pump housing and a slack diaphragm pumping element within the housing which is reciprocally displaceable in response to fluid pressure on one side thereof to indraught and exhaust a fluid on the other side thereof. Novelly thepump is free of shafts or other actuating means connected to the pumping element, to remove a source of mechanical failure.

This invention relates generally to fluid pumping systems, and is directed particularly to a novel system wherein pumping motivation is achieved by the pressure pulsing of a fluid stream with corresponding response by a reciprocally displaceable pumping element, to the exclusion of mechanical or disruptive driving connections with the pumping element.

The present system is predicated generally upon the concept of maintaining a flow of fluid which undergoes restriction by an aspirator, eductor or venturi effect to create a lower or negative pressure, an intenmittently restricting or closing the fluid flow downstream of the as pirator to create a higher or positive pressure, these pressures being communicated to a pumping element, e.g. diaphragm, which is deflected in response to the pressure changes to pump a second fluid stream.

In a typical situation a motive fluid stream adequately pressurized in accordance with a desired pump output pressure, is discharged through a venturi-like restriction connected to the motive side of a diaphragm pump chamber so that suction displacement of the diaphragm occurs in response to the venturi-induced pressure reduction. Reverse or pumping displacement of the diaphragm at predeterminable intervals is accomplished by valving the motive fluid downstream from the venturi, thus to create a cycle back pressure also transmitted from the venturi to the diaphragm for its pumping actuation.

My primary object accordingly is to provide a pumping system so constituted in which the pumping element or diaphragm has floating operating characteristics in that it need be subjected to no high or disruptive pressure differentials, and long performance life of the diaphragm is further assured by the absence of any requirement for mechanical driving connection therewith.

By attenuating the rate of displacement of the actuating fluid by means of suitable restricting orifices, metering valves, or by-pass circuits, it is possible to control the peak values of positive and negative pressures exerted on the diaphragm or equivalent and thereby to make the pump suitable for such uses as handling whole blood and other pressure sensitive fluids.

In more specific reference to pressure pulse creation and control, the invention has for its further object to provide for mechanical actuation of the pressure cycling valve at predetermined frequency, and for variably selecting and maintaining such frequency by an appropriate timing means which controls the valve actuator.

A further object of the invention is to provide a simple and effective system for proportioning the liquid streams, i.e. the motive and pumped streams, at constant or variice able ratios, thus ultimately to deliver the streams separately, or together as a mixture. Thus the invention becomes a desirable and dependable means for the addition of chemical or other additives in controlled ratio to a bulk motive fluid stream.

All the various features and objects of the invention will be more fully understood from the following detailed description of illustrative embodiments shown by the accompanying drawing, in which:

FIG. 1 is a general diagrammatic showing of the pumping system; and

FIG. 2 is a fragmentary view showing a variational form of pump.

Referring to FIG. 1, the main or motive fluid is conducted through line 10 from any suitable supply source 12 for final delivery to such disposition of the fluid as may be desired, as for example into tank 13. As illustrative, line 11 may conduct a stream of water at pres.- sure sufliciently high for the required velocity effect at the later described eductor and for pressurizing the pump to operate against a given head or back pressure. Line 11 may contain a shut-01f valve 14, and beyond the valve a venturi-type eductor or aspirator generally indicated at 15 and of known design operable to induce negative or low pressure communicated to the pump generally indicated at 16. Diagrammatically, the eductor 15 is shown to have a constricted throat formed by the venturi 17 which is in communication through line 18 with the pump.

Downstream from the venturi, line 10 contains a valve 19 coupled to an actuator 20, for example of the solenoid type, which in turn is coupled to an appropriate timing device 21. The valve 19 opens and closes intermittently under the influence of the actuator 20 to open and close or restrict the liquid flow through line 10, and the frequency of the valve action is governed by the timer 21 as by pressure control through feed-back loop 22 connecting with line 10 at the upstream side of the valve 19, or the timer 21 may be independently controlled and operated as by employing any of various known types of electrical timers variably adjustable to cause actuation of the solenoid device 21 at any of selected predetermined intervals.

The pump 16 is shown to be of a diaphragm type having

chamber sections

23 and 24, the inside surface 23a and 24a of which ideally may be smoothly shaped to paraboloidal curvatures concentric with the chamber sections. Peripherally clamped and sealed at 241 between the sections is a flexible and preferably somewhat elastic diaphagm 25 which deflects alternately against the surfaces 23a and 24a respectively during section and pumping displacements of the diaphragm. Because capacity of the system to permit operation of the pump at low pressure diiferentials in the

chambers

26 and 27 at opposite sides of the diaphragm, the latter may be made of thin and flexible material having substantial elasticity, without danger of rupture. The durability of the diaphragm over long periods of performance is further assured by its floating freedom without attachment to the usual mechanical actuators which impose, at least in the course of time, severe strengths and disruptive influences.

Fluid enters and discharges from the pump chamber 27 through an orifice or line 28 communicating with a suction line 29 leading from a source of liquid such as a chemical additive contained in vessel 30. Line 29 contains a check valve 31 which closes to prevent reverse flow of the line fluid during pumping displacement of the diaphragm. Line 32 conducts the pumped fluid to suitable disposition which may or may not be independent of the motive fluid stream delivered through line 10. Where the pump is employed in a mixing system for the introduction of an additive to the main stream liquid, line 32 may connect into line beyond the valve 19, or lead directly to the tank 13. Line 32 contains a check valve 33 which prevents reverse line liquid flow during suction displacement of the diaphragm 25.

FIG. 2 illustrates a variational feature of the invention wherein, instead of the diaphragm pump, there is connected between lines 28 and 18 a piston type pump shown diagrammatically to comprise a cylinder 34 containing a floating piston 35 displaceable reciprocally within the cylinder in response to applied pressure differentials.

Reference previously has been had to possible desirability of attenuating the rate of effective displacement of actuating fluid against the diaphragm, and to control peak values of positive and negative pressures exerted on the diaphragm. While such attenuation may be accomplished in various manners, as illustrative, line 18 is shown to contain a valve 40 which may be manually adjusted to variably throttle the pressure transmission between the eductor and diaphragm 25, and in so doing to correspondingly control limiting positive and negative pressures applied to the diaphragm.

In certain instances it may be desirable to employ the system of FIG. 1 for the pumping of an additional secondary or additive liquid, utilizing the same motive fluid stream in line 10 and the same eductor 15. Thus line 18 is shown to connect with a branch line 41 leading to pump generally indicated at 42, which as illustrative of a further variational form of pump, is shown diagrammatically to comprise a body or cylinder 43 containing a flexible tubular pumping element or diaphragm 44 terminally sealed at its ends within the body 43 to be subject to intermediate radial compression and expansion in response to the pressure transmission through line 41. The ends of the body 43 may carry

check valves

45 and 46 corresponding respectively to

valves

31 and 33.

Upon communication of lowered or negative pressure through line 41 to space 47 outside the element 44, the latter resiliently or elastically expands to draw into the pump liquid through line 48 leading from a supply source 49. Then as the motive fluid stream is pulsed, the resulting communication of positive pressure to space 47 radially constricts the element 44 to discharge the liquid through line 50 to suitable disposition, as into the vessel 13.

Thus the system may be employed to pump one or more secondary or additive liquids in response to eductive and pulsing etfects of a main or motive fluid stream in line 10. This stream may be a liquid, or the motive fluid may be a gaseous stream operating to pump in the manner explained two or more secondary or additive streams.

In the operation of the system, at such time as the valve 19 is open, the motive fluid flow through the eductor 15 creates a negative or reduced pressure communicated through line 18 to chamber 26, causing deflection of the diaphragm to a limit of conformed engagement against the surface 23a. Upon closure of the valve 19, the line 10 pressure is communicated from the eductor to the diaphragm 25, deflecting the latter to an ultimate limit of pumping displacement in engagement with the chamber surface 24a. And as previously indicated the frequency of the diaphragm deflections and therefore the ratio of pump additive fluid to the motive fluid, is governable both closely and within wide ranges by the frequency of valve actuation as controlled by the timer 21.

I claim:

1. A fluid pumping system comprising a pump having a chamber and a fluid impermeable reciprocally displaceable pumping element having a freely floating portion extending within said chamber to form fluid tightly separated zones therein, conduit means connected to the chamber zone at a first side of said element for conducting fluid to and from the chamber, means forming a fluid passage containing a restricted eductor connected to the chamber zone at a second side of said element to cause displacement thereof in one direction in response to reduced pressure communicated by virtue of fluid flow through the eductor,

and means for intermittently closing said fluid passage at the discharge side of the eductor to the extent of causing transmission intermittently of positive pressure from the eductor to said chamber and resultant pumping displacement of said element in an opposite direction.

2. A pumping system according to claim 1, in which said conduit means comprises a suction line containing a valve preventing reverse fluid flow upon pumping displacement of said element, and a discharge line containing a valve preventing reverse flow therein upon reverse displacement of said element.

3. A pumping system according to claim 1, in which said element is a peripherally supported flexible diaphragm.

4. A pumping system according to claim 1, comprising also means operatively associated with the last-mentioned means for controllably varying the rate of pressure communication from said eductor to said element.

5. A pumping system according to claim 1, comprising a second pump having a fluid inlet and outlet and containing a second pumping element having a freely floating reciprocally displaceable central section in pressure transmitting. communication with said eductor.

6. A pumping system according to claim 1, in which the last mentioned means comprises a valve, a powered actuator for the valve, and means for intermittently energizing said actuator to operate the valve.

7. A pumping system according to claim 6, in which said fluid passage connects with .a pressurized liquid source and said conduit means comprises a suction line communicating with a second liquid source and a discharge line, and means combining the liquids discharged through said passages and discharge line.

8. A pumping system according to claim 7, in which said discharge line connects with said passage at the downstream side of said valve.

9. A pumping system according to claim 8, in which said element is a peripherally supported flexible diaphragm and said conduit means comprises pump chamber suction and discharge lines and reverse fiow check valves in said lines.

References Cited UNITED STATES PATENTS 862,867 8/1907 Eggleston 230162 X 2,141,427 12/1938 Bryant 103-235 2,238,747 4/1941 Ornstein 13799 2,954,737 10/1960 Hoover 103-38 3,114,379 12/1963 Cordis 13799 X ROBERT M. WALKER, Primary Examiner.

Claims

1. A FLUID PUMPING SYSTEM COMPRISING A PUMP HAVING A CHAMBER AND A FLUID IMPERMEABLE RECIPROCALLY DISPLACEABLE PUMPING ELEMENT HAVING A FREELY FLOATING PORTION EXTENDING WITHIN SAID CHAMBER TO FORM FLUID TIGHTLY SEPARATED ZONES THEREIN, CONDUIT MEANS CONNECTED TO THE CHAMBER ZONE AT A FIRST SIDE OF SAID ELEMENT FOR CONDUCTING FLUID TO AND FROM THE CHAMBER, MEANS FORMING A FLUID PASSAGE CONTAINING A RESTRICTED EDUCTOR CONNECTED TO THE CHAMBER ZONE AT A SECOND SIDE OF SAID ELEMENT TO CAUSE DISPLACEMENT THEREOF IN ONE DIRECTION IN RESPONSE TO REDUCED PRESSURE COMMUNICATED BY VIRTUE OF FLUID FLOW THROUGH THE EDUCTOR, AND MEANS FOR INTERMITTENTLY CLOSING SAID FLUID PASSAGE AT THE DISCHARGE SIDE OF THE EDUCTOR TO THE EXTENT OF CAUSING TRANSMISSION INTERMITTENTLY OF POSITIVE PRESSURE FROM THE EDUCTOR TO SAID CHAMBER AND RESULTANT PUMPING DISPLACEMENT OF SAID ELEMENT IN AN OPPOSITE DIRECTION.