Pump control valve

Abstract

A pump control valve for use between a motor driven pump and a fluid storage and supply tank. The pump control valve is operative to control the run time of the pump by controlling the fluid supplied to the tank between a maximum of fluid supplied to a minimum of fluid supplied during the time period in which the tank pressure is brought to the desired limit.

Description

BACKGROUND OF THE INVENTION

This invention is directed to a pump control valve which is operative to control the run time of a motor driven fluid pump. Normally, the switches which activate and deactivate a fluid pump motor are pressure activated, i.e. they activate the fluid pump when the tank pressure reaches a pre-selected low and deactivate the fluid pump when the tank pressure reaches a pre-selected high. Normally, these pressures run between 40-60 psi, although this range may vary as desired. Fluid pumps, in most circumstances, are capable of delivering a volume of fluid which raises the pressure within the tank to its upper limit in less than one minute. Over an extended period of time, this type of minimal run time is very damaging to the fluid pump motor.

It is a primary object of the instant invention to extend the run time of the motor of a fluid pump allowing the pump to slowly shut off.

Another object of the invention is to provide a corrosion free valve which is not affected by saltwater or atmosphere of coastal areas.

Another object of the present invention is to provide a pump control valve which is adjustable between tank pressure and desired fluid pump run time.

Another object of the invention is a fluid pump control valve which is adjustable without tools.

SUMMARY OF THE INVENTION

A pump control valve adapted to control the run time of a motor driven pump by variably controlling the flow of fluid between the motor driven pump and the distribution tank. The pump control valve includes a housing having a first chamber and a second chamber. The first chamber has an inlet connected with the pump and the second chamber has an outlet connected with the tank. The first chamber is connected with the second chamber through a first opening, which allows a continuous rate of fluid flow and a second opening which has a greater but interruptable rate of fluid flow.

A diaphragm arranged over the second opening is operative to seal the second opening and interrupt fluid flow through the second opening and between the first and second chambers. The diaphragm is also operative to unseal the second opening and allow fluid flow between the first and second chambers.

A third chamber is arranged adjacent the first and second chambers and above the diaphragm. An inlet opening is provided connecting the third chamber with the first chamber, which opening allows fluid from the first chamber to enter the third chamber at a fixed rate. When sufficient fluid is in the third chamber, it causes the diaphragm to seal the second opening of the first chamber.

An outlet opening, including an adjustable valve, is provided in the third chamber providing controlled and adjustable rate of fluid flow out of the third chamber into the second chamber. The third chamber outlet controls the time required for sufficient fluid to accumulate within the third chamber to cause the diaphragm to close the second opening. The rates of fluid flow into the tank are varied by as much as ⅔. By opening and closing the second opening, this arrangement controls the rate of fluid flow into the tank, and thereby, controls the time required to build the pressure within the tank to a sufficient level to cut off the pump.

The valve associated with the third chamber is interconnected with a control chamber which includes a dial which acts to control the valve to adjust the rate of fluid flow through the outlet opening to cause closure of the diaphragm to coincide with a pre-selected tank pressure. The dial includes a pointer and indicia indicating tank pressures. The pointer, when positioned at selected indicia, causes the pressure within the third chamber to build sufficiently to cause the diaphragm to close the opening upon the tank reaching a pressure representing only a portion of the pressure necessary to cut the pump off.

A system for increasing the run time of a fluid pump including a fluid storage and delivery tank, a motor driven fluid pump for delivering fluid to the tank and a pump control valve for controlling the length of run time of the fluid pump. The system includes a fluid delivery line carrying fluid from the fluid pump to the pump control valve and from the pump control valve to the tank. There is a pressure switch associated with the tank which is operative to actuate the pump when the pressure within the tank drops below a set point and to deactivate the pump when the pressure, within the tank, rises above a set point. The pump control valve includes an intake chamber for receiving fluid from the pump, an output chamber for expelling fluid to the tank, and a flow regulating control including a regulating dial for automatically controlling the rate of fluid flow through the pump control valve between high and low volumes.

In operation, the pressure switch activates the fluid pump to deliver fluid to and through the pump control valve, which first allows fluid to pass at high volume until a selected intermediate pressure is obtained within the tank, whereupon the pump control valve acts to reduce the rate of fluid flow to the tank and to continue flow at the lower rate until the fluid pressure switch deactivates the pump.

The pump control valve includes a first opening interconnecting the intake and output chambers, a second and smaller opening also interconnecting the intake and output chambers and a diaphragm operative to close the first opening. The diaphragm is controlled by the flow regulating control to move between an open and a closed position to allow or stop the flow of fluid through the first opening.

There is a third chamber adjacent the first and second chambers. The third chamber is operative to control a diaphragm operative to open and close a main opening interconnecting said first and second chambers.

It is desirable that the pump control valve resist corrosion. It is, therefore, preferred that the major members be made of plastic and the interconnecting members, i.e. screws, etc. be made of stainless steel.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cutaway plan view of the pump control valve of the invention with the diaphragm in the closed position.

FIG. 2 is a cutaway plan view of the pump control valve of the invention with the diaphragm in the open position.

FIG. 3 is a top view of the pump control valve.

FIG. 4 is a diagrammatic view of the system in which the pump control valve is operative.

DESCRIPTION OF A PREFERRED EMBODIMENT

Turning now to FIG. 4, there is shown a general schematic of a fluid supply system in which the pump control valve 10 of the present invention may be incorporated. The fluid supply system includes the supply of fluid 12, the supply pipe 14, the delivery pipe 15, the fluid storage tank 16, the fluid delivery pump 18, the pressure control switch 20 and a power supply 21, 22, which supplies electrical power to the switch from the switch to the pump.

The pressure control switch 20, which may be of any usual type, is connected with the fluid pump 18 by an electrical lead 22. Switch 20 is normally set with a twenty pound range, i.e. with a 40-60 psi setting, the switch would activate the pump when the tank pressure reaches 40 psi and would deactivate the pump when the pressure reaches 60 psi. This range may vary between highs and lows but spread generally remains the same. Under normal conditions, the pump can supply the tank with fluid so that the pressure limit is reached in about one minute. It has been found that such short run times are damaging to the pump.

The pump control valve 10 of the instant invention provides a simple, cost efficient and durable system for prolonging the run time of the fluid pump used in fluid supply systems as shown in FIG. 4.

Turning now to FIGS. 1 and 2, the pump control valve of the invention is shown in its primary or partially closed position in FIG. 1 and in its secondary or open position in FIG. 2. Valve 10 comprises an intake duct 24 communicating with first chamber 28, an outlet duct 26 communicating with second chamber 30 and third or upper chamber 32 which acts to control the movement of diaphragm 34. It is noted that diaphragm 34 is assisted to its closed position by spring 34′. Spring 34′ is a low pressure spring.

Connected with third or upper chamber 32 and second chamber 30 is a pressure control system 36 which includes control chamber 38 with valve 40 connected with positioning member 42.

First chamber 28 is connected to second chamber 30 by way of first opening 44 and second and larger opening 46 and to the pump by pipe 14. The first chamber is also connected with third chamber 32 by way of opening 48 through diaphragm 34.

Third chamber 32 is connected with control chamber 38 by passageways 50, 51 and 52. Control chamber 38 is connected to second chamber 30 by way of passageway 54.

The fluid flow patterns, through the control valve, can be seen by arrows, first in FIG. 1 indicting the restricted fluid flow to chamber 30 through only openings 44 and 54. In FIG. 2, the arrows depict the full fluid flow to chamber 30 through openings 44, 54 and 46.

Valve 40 is mounted for vertical movement along frame 56 by way of threaded shaft 57 and screw arrangement 59, which carries control knob 58. Knob 58 is connected to shaft 57 and carries pointer 62 while self 60 is numbered to identify psi and the corresponding BAR. The outlet opening of control chamber 38 is sized by moving valve 40 vertically relative to outlet passageway 54. This is accomplished by rotating control knob 58 to the left or right until the appropriate pointer 59 is aligned with the desired psi. Movement of knob 58 moves valve 40 vertically varying the opening to outlet 54. The settings are present to allow fluid to escape through passageway 54 to close diaphragm 38 when the intermediate point of the pressure control range is met.

In practice, with tank 16 at a desired pressure of 60 psi, control valve 10 is at rest, or in its primary position, as seen in FIG. 1 with diaphragm 34 closing outlet 46 and with pump 18 off. Upon the release of fluid from tank 16, the pressure drops in the tank and also in the line between the supply tank and the pump to below 40 psi, whereupon the pump is activated. The fluid enters first chamber 28, forces open diaphragm 34 as it passes through opening 46 into second chamber 30 and out through outlet 26. Simultaneously, the fluid passes through opening 48 into chamber 32. As chamber 32 fills, fluid escapes through passageways 50, 51 and 52 into control chamber 38. The rate of fluid discharge from control chamber 38 controls the time or rate of pressure build-up in upper chamber 32, which in turn controls the time that diaphragm remains in its open position.

When sufficient pressure has built up in upper chamber 32, diaphragm 34 is forced downward to close opening 46. With opening 46 closed, fluid passes from first chamber 28 to second chamber 30 only through opening 44 and through opening 48, passageways 50, 51, 52 control chamber 38 and passageway 54. The rate of fluid flow to second chamber 30, and subsequently, to tank 16 is reduced by between ½ and ⅔ compared to the flow rate when opening 46 is clear. This lower flow rate allows the pump to run at least twice as long as it would without the control valve resulting in a slow shutoff.

The control valve is installed between the pump and tank. The control valve is set to the appropriate psi. For example, if the pressure control switch is set at 40-60 psi, the control valve is set at 50 psi. The valve is pre-constructed to control the rate of fluid flow through upper chamber 32, thereby controlling the time required for pressure to build-up in chamber 32 sufficient to move diaphragm 34 to close opening 46. This closure is correlated with the psi in tank 16 reaching 50 psi or the mid-point of the set range.

Other settings are available for other selected psi ranges. It is preferred that diaphragm always closes at about the mid-point of the psi range.

Claims

1. A pump stop valve for variably controlling the flow of fluid between a motor driven pump and a distribution tank to control the run time of said pump, said valve comprising:

a housing having a first chamber having an inlet connected with said pump and a second chamber having an outlet connected with said tank;

said first chamber connecting with said second chamber through a first opening allowing a continuous flow rate and a second opening having a greater but interruptable flow rate;

a diaphragm arranged over said second opening, said diaphragm being operative to seal said second opening to prevent fluid flow through said second opening between said first and second chambers and to unseal said second opening and allow fluid flow between said first and second chambers;

a third chamber arranged adjacent said first and second chambers and above said diaphragm;

an inlet opening connecting said third chamber with said first chamber allowing fluid at a fixed rate to enter said third chamber wherein sufficient of said fluid within said third chamber causes said diaphragm to seal said second opening of said first chamber;

an outlet opening provided in said third chamber providing an adjustable rate of fluid flow out of said third chamber into said second chamber, said third chamber outlet variably controlling the time required for said fluid within said third chamber to cause said diaphragm to seal closing said second opening; whereby,

the run time of said pump is controlled to selected time periods by controlling the rate of fluid flow to said tank to vary by as much as ⅔ between start and stop.

2. The pump stop valve of claim 1 wherein said third chamber includes a dial overactive to adjust said rate of fluid flow through said outlet opening to cause closure of said diaphragm to coincide with a pre-selected tank pressure.

3. The pump stop valve of claim 2 wherein said dial includes a pointer and indicia indicating tank pressures wherein said pointer is positioned to point at selected indicia causing said diaphragm to close said opening upon said tank reaching the selected pounds of pressure.

4. The pump stop valve of claim 1 wherein said valve housing is made of plastic.

5. A system for increasing the run time of a fluid pump including a fluid storage and delivery tank, a motor driven fluid pump for delivering fluid to said tank and a pump stop valve for controlling the length of run time of said pump, said system comprising:

a fluid delivery line carrying fluid from said pump to said pump stop valve and from said pump stop valve to said tank;

a pressure switch with said tank operative to actuate said pump when pressure within said tank drops below a set point and to deactivate said pump when said pressure, within said tank, rises above a set point;

said fluid stop valve having an intake chamber for receiving fluid from said pump, an output chamber for expelling fluid to said tank, and a flow regulating control including a regulating dial for automatically controlling the rate of fluid flow through said pump stop valve between high and low volumes; whereby,

said pressure switch activates said fluid pump to deliver fluid to and through said pump stop valve at said high volume until a selected intermediate pressure is obtained within said tank, whereupon said pump stop valve is actuated to reduce the fluid flow through said valve to said low volume until said fluid pressure switch deactivates said pump.

6. The system of claim 5 wherein said pump stop valve includes a housing made of plastic.

7. The system of claim 5 wherein said pump stop valve includes a third chamber adjacent said first and second chambers, said third chamber controlling a diaphragm operative to open and close a main opening interconnecting said first and second chambers.

8. The system of claim 5 including a first opening interconnecting said intake and output chambers, a second and smaller opening interconnecting said intake and output chambers and a diaphragm controlled by said flow regulating control operative to move between open and closed positions to allow or stop fluid flow through said first opening.