US2713826A - Fluid pumping system - Google Patents

Description

y 26, 1955 w. H. TINKER 3,

FLUID PUMPING SYSTEM Filed Aug. 6, 1949 2 Sheets-Sheet 1 INVENTOR WALTER H. TINKER ATTORNEY July 26, 1955 w. H. TINKER FLUID PUMPING SYSTEM Filed Aug. 6, 1949 2 Sheets-Sheet 2 2 FIG. 2.

J62 6' U .77 H 53 W 76 FIG. 3 /u 6/ 76 4 72 l i L w INVENTOR T 7 U WALTER H. TINKE 7/ 7// g 1% W ATTORNEY United States Patent Hal FLUID PUMPING SYSTEM Walter H. Tinker, St. Louis, Mo., assignor to Fairbanks, Morse & Co., Chicago, 11]., a corporation of Illinois Application August 6, 1949, Serial No. 109,047

13 Claims. (Cl. 103-2) This invention relates to fluid pumping systems characterized by the employment of a pumping unit arranged in a system for supplying fluid to a domestic supply system and for irrigation uses and the like.

The invention is embodied in the combination of a pumping unit to be located near or at substantially ground levels relative to the source of fluid supply, and a jet pump connected into the pumping unit and acting to lift the fluid into the suction influence of the pumping unit, such as might be the case in connection with deep well installations. In a combination of this character, it is a purpose hereof to employ the pumping unit for dual service operation, whereby one pump installation may service a domestic load and a general purpose load, as irrigation and the like. The general practice is to provide the domestic load by the use of a storage tank maintained under a desired pressure, thus the pumping unit must have a pressure discharge sutficient for this purpose. On the other hand, the irrigation load does not require or often need a high pressure supply of fluid and may be handled by a suitable conduit provided with a shut-off valve.

The invention contemplates the use of a two stage pumping unit having axially located impellers in series relation for developing high and low pressures at suitable discharge outlets, with a suflicient portion of the fluid recirculated at pressure suflicient to energize a jet pump located in the well or other source of fluid. The high pressure outlet is connected to a domestic service supply tank, the low pressure outlet has a conduit for directing its discharge, and the flow in each conduit of the system is regulated by a pressure responsive switch in the pump motor circuit and by a device disposed in and between the discharge conduits of the pump for diminishingor modulating low pressure flow when the supply tank requires replenishment from the high pressure discharge.

The regulating device includes a valve in the low pressure conduit and a piston member in the high pressure conduit which is lifted or moved to modulate the opening and closing of the valve due to the dynamic force effect of fluid flowing in the high pressure conduit. The piston and valve are connected and are arranged to move in a valve opening direction due to gravity effect, when the flow of high pressure fluid is insuflicient to lift the same. The high pressure conduit is provided with a check valve on the tank side of the regulating device to prevent flow away from the tank, once it has been brought up to pressure and the pressure switch has acted to determine the operating period of the pumping unit.

Thus, each time domestic use from the tank depletes the pressure, the pressure switch will start the pumping unit and the high pressure flow will cycle the regulating device to diminish or prevent low pressure discharge until the tank is replenished. Ordinarily this system might prevent any substantial low pressure discharge, but by the provision of a shunt circuit to the motor, or by a selected setting of the pressure responsive switch with respect to required jet pump pressure, the pumping unit canbe conditioned to afford low pressure discharge. When the ice shunt circuit is in use, the regulating device operates automatically to replenish the domestic supply tank and maintain the desired pressure, with the low pressure conduit receiving the full fiow from the pump when the tank has been fully replenished and there is no longer a suflicient flow force or pressure drop across the device to close the low pressure conduit valve.

The objects of the present invention, in furtherance of the aims above stated, are to carry out the principles of the above pumping system by the provision of an improved dual pressure pumping unit connected for dual discharge service and with such improved regulating and control means as will permit of an effective and economical systern.

A presently preferred embodiment of the invention is disclosed in the accompanying drawing, wherein:

Pig. 1 is an assembly view of a pumping system showing the dual discharge pump unit in combination with a jet pump for deep well application, and in which the control devices are shown for regulating replenishment of the domestic storage tank and a general purpose discharge;

Fig. 2 is a sectional elevational view of the pump unit showing the dual pressure pump impeller, and

Fig. 3 is a sectional elevational view of the fluid flow regulating device associated with the discharge conduits of the pumping unit.

Referring to Fig. 1, the assembly of the pumping system may be seen to include a motor operated pumping unit associated with a jet pump unit 11, and in which the pumping unit is provided with a high pressure discharge conduit 12 connected into a domestic pressure storage tank 13 and a low pressure discharge conduit 14 leading to a point of discharge beyond a manually controlled valve 15. The pumping system thus designated also includes a pump discharge control and modulating device at 16, and an automatic pressure operated switch 17 connected into the tank supply conduit so as to be responsive to pressure thereof. The switch 17 receives its current sup ply from a main switch control box 17 by lead 19, and the lead 20 from the switch 17 connects into the junction box 21 for the motor 22 of the pumping unit 10. A manual switch 23 is connected in shunt of the pressure responsive switch 17 by the leads 24 and 25 so that the switch 17 may be disabled when it is desired to operate the motor 22 independently of pressure conditions at tank 13.

The tank 13 is provided with the domestic service con duit 26 having the usual shut-off valve 27 therein. In addition, the conduit 28 connecting between the device 16 and the tank 13 is provided with an auxiliary faucet valve 29 for use when it is desired to reduce tank pressure for cycling the pressure switch 17 to initiate pump motor operation, as will be described presently.

Turning now to Fig. 2, the pump assembly of unit 10 comprises the base casting 30 provided with the suction chamber 31 having a bottom tapped port 32 associated with the suction conduit 33, and a high pressure discharge chamber 34 surrounding the chamber 31 and provided with a bottom tapped port 35 for the jet pump feed pipe 36, and a side port to which conduit 12 is connected. Chamber 34 is defined in part, by the high pressure impeller bowl 37, and both the bowl 37 and chamber 34 are closed by the cover structures 38. The cover forms the mounting bracket for motor 22, and is also formed with a second or low pressure impeller bowl constituted by the spaced transverse walls 39 and 49. The second impeller bowl is provided with a spiral or volute discharge channel 41 which delivers at the space 42, and this space is provided with a suitable discharge port to which conduit 14 is connected.

The serially related, coaxially positioned pumping impellers are integrally formed to include the larger high pressure impeller 43 and the smaller or low pressure impeller 44. The suction eye 45 of the impeller 43 opens to chamber 31, and the suction eye 46 of impeller 44 is located axially beyond the eye 45 to receive fluid flowing thereto past the high pressure impeller 43. The motor shaft 47 is suitably connected with the combination impeller structure for direct drive thereof, and a shaft sealing assembly is mounted in the wall extension 48 of the low pressure impeller bowl. impeller bowl 37 is provided with a volute channel 49 which opens to chamber 34 at port 50.

In Figs. 1 and 2, the pressure discharge conduit 36 connects into a jet pump fitting 51 for energizing the same to lift fluid through foot valve 52 and into the venturi tube 53 for flow to the suction conduit 33. The fluid is then pumped by the impellers 43 and 44 for discharge into the respective spaces 34 and 42. The high pressure fluid in space 34 divides, part returning to the jet pump 11 at port 35 and part flowing to the discharge conduit 12. The full discharge from impeller 44 and space 42 flows to the conduit 14 for discharge past the valve 15, when the latter is open.

Referring to Figs. 1 and 3, the flow modulating or regulating device 16 is constituted by the valve body 55 and the threadedly connected cylindrical body 56. The body 55 has its fluid inlet side connected to conduit 14 and its outlet side associated with a conduit 57 in which the valve 15 is placed. An internal wall 58 of the body 55 is formed with a seat 59 for the valve element 60. The cylindrical body 56 is formed with a bore 61 for a valve operating member comprised of a piston 62 and a piston rod 63. The bore 61 is closed at one end by a cap 64 in which a socket 65 is provided for guiding the lower end of rod 63, the opposite end of rod 63 being slidably disposed in the transverse wall 66 to extend into operating connection with the valve 60, as by means of the head element 67 fixed to the rod and the clamping collar 68 threaded into the under side of the valve 60. To allow for free, gravity influenced downward motion of the piston and rod, the guide socket 65 is provided with radial passages 69 which open to an annular channel 70 so placed as to communicate with a radial passage 71 and a longitudinal passage 72 formed in the body 56 and opening into the discharge space of body 55 below valve 60.

It will be noted in Fig. 3 that the body 56 is provided with a tapped inlet port 73 for the pump discharge conduit 12, and with a body extension 74 at an outlet port 75, the body extension 74 receiving a fitting 76 for mounting a check valve 77 in closing relation over the port and to which conduit 28 connects. A spring 78 is employed to urge the valve 77 in a closing direction so that fluid in the tank 13 may not back up in conduit 28 and initiate a reverse flow through the body 56. The showing of Fig. 3, except for the closed condition of the check valve 77, illustrates the action of the piston 62 when the pressure drop across the device has induced the full force of fluid flow from conduit 12 to conduit 28, and it is this induced flow which causes an elevation thereof such as to close the valve 60 on its seat 59 and prevent low pressure discharge at conduit 57. Thus, the

The high pressure fluid output of pumping unit 10 is directed into tank 13.

In a regulating device of this character, it is important that the inlet port 73 and outlet port 75 be off-set, or otherwise arranged so that the piston element 62 moves between the ports and cannot block either port when in its fully raised or lowered positions. Also the downward stroke of the piston is limited so that the upper portion of port 73 is blocked, while the lower portion is open to permit the introduction of high pressure fluid below the piston. In its fully raised condition as shown, the piston is stopped at a location across but not blocking port 75, so that the static pressure developed in bore 61 sponsive switch 17 connected into the motor circuit.

is the same on both sides. By this arrangement, the dynamic flow force below the piston is usefully applied and sustains the piston 62, even though fluid at low pressure is above the valve 60. When the piston 62 has moved downwardly so that it interrupts communication between ports 73 and 75, it acts as a check valve, the same as valve 77. However, due to wear and the need for a sliding fit in bore 61, the piston 62 will allow some leakage, whereas valve 77 is positive.

With the pressure responsive switch 17 in the motor circuit and valve 15 in closed condition, the normal automatic operating periods of the pump unit 10 will be determined by pressure conditions in the tank, as reflected in conduit 28. Thus, when the switch 17 is operated to cut-in at a predetermined low pressure, as upon the creation of a drop in pressure due to domestic drawoff at line 26, the pump unit 10 will operate to discharge fluid at both conduits 12 and 14. The pressure in conduit 12 being higher, the fluid flow will force piston 62 upwardly to open communication between ports 73 and 75, and direct a substantial flow to the tank 13 past check valve 77. It is highly important in a system of this type to throttle the low pressure flow so that the prime on the pump will not be lost. Attainment of a predetermined desired pressure in tank 13 will serve to cut-out or open switch 17 and shut down the motor 22. At this time, the check valve 77 acts to prevent fluid flow reversal in conduit 28 as the piston 62 falls. With the pump now stopped, and because of the check valve 77, the tank 13 cannot be depleted through the pump if valve 15 should be opened. However, the pump can be started by opening the faucet valve 29 to drop the tank pressure to the pre-set starting condition at switch 17. The usefulness of valve 29 will be described presently.

When the shunt switch 23 is closed to take the pressure switch 17 out of the motor circuit, the pump unit 10 operates continuously to discharge fluid at conduits 12 and 14. Opening of valve 15 now establishes a general purpose, low pressure fluid supply. If the tank 13 is fully charged, the pressure drop between ports 73 and 75 will not be such as to create a dynamic flow effect under the piston 62, and the same will remain in its lowered position to open valve 60. Should tank drawoff deplete the pressure therein, the pressure drop across the piston 62 will initiate fluid flow toward the tank. This flow elevates the piston 62 and concurrently modulates or diminishes flow past valve 60 by moving the same toward its seat 59. After the tank 43 has been replenished, the device 16 again acts to increase flow past valve 60.

There is a further advantageous operation of the pumping system in which a substantial low pressure supply of fluid may be created with the automatic pressure re- 1f. the pressure at which the switch 17 operates to stop the pump motor 22 is set higher than the pressure required to eificiently operate the ejector of the jet pump unit 11, a condition will be reached where the fluid delivery to the tank will never quite build up tank pressure sufficient to operate the switch 17 to stop the pump motor. This condition is attained when the low pressure valve 15 is open, and the system will operate on a continuous basis with the device 16 modulating the fluid flow in both conduits. As an example: assume the pump pressure for eflicient ejector operation to be 55 pounds and the switch 17 set to cut-out or stop motor operation at 60 pounds. Now, if the tank 13 is up to 60 pounds pressure as by operating the pump with the valve 15 closed, the system will remain quiescent regardless of opening of the valve 15. But should the faucet valve 29 be opened to drop the tank pressure to the cut-in pressure set at switch 17, the switch 17 will start motor operation, after which valve 29 can be again closed. Now the pump starts operation to replenish the tank 13, but a portion of the fluid will flow past valve 15. As the tank pressure approaches ejector operating pressure of 55 pounds, the flow at valve 15 progressively increases, due to the modulation action of device 16, and the tank pressure increase levels off at about the ejector operating pressure. In other Words, as the predominate effort of the pumping unit to replenish tank 13 builds up the tank pressure close to the ejector operating pressure, the latter pressure being substantially the pressure in conduit 12, the resulting back pressure from tank 13 or the equivalent decreasing pressure drop across the ports 73 and 75 of device 16 causes the piston 62 to drop, thereby opening valve 60 to a greater degree. The progressive opening action at valve 6% permits more fluid to be discharged through conduit 14 and concurrently reduces the quantity of fluid capable of being delivered to tank 13. Since the pressure in conduits 12 and 28 reflects the ejector operating pressure, it becomes possible to select a pressure for the cut-out action of the automatic switch 17 which is just enough higher than the required ejector n operating pressure to delay the cut-out action of the switch 17 until valve 15 is closed. As long as valve 15 remains open, under this last stated condition, the tank 13 never quite becomes replenished, but it is maintained at a pressure suitable for the purpose desired.

In a system of this character, it has been found highly desirable to employ the regulating device 16 in order to accelerate the rate of replenishment of fluid in tank 13 by temporarily imposing a throttling action on the low pressure discharge. Thus, the imposition of severe use loads on the fluid in tank 13 can be recovered in a short period of maximum pumping effort. As was pointed out above, the throttling action of device 16 relative to low pressure fluid discharge acts to maintain the pump primed by retaining fluid in the system.

It should now be clear in what manner and to what extent the present system will function as a dual service pumping installation. While the presently described parts and units of the system will serve in the manner intended, it should be understood that equivalent parts and units may be substituted for those shown Without departing from the scope of the claims hereunto appended.

What is claimed is:

1. In a pumping system, a motor operated pumping unit having two discharge outlets, one discharge outlet being located to deliver at a pressure less than the delivery pressure of the other, a conduit leading from one of said discharge outlets to a point of delivery, a pressure tank, a conduit connecting said tank with the other of said discharge outlets, a valve inserted in the first mentioned conduit, and a control member disposed in the other of said conduits for operation to open the latter conduit in response to flow of fluid toward said tank,

said member being connected with said valve for operating said valve in a closing direction during fluid flow toward said tank.

2. In a pumping system, a motor operated pumping unit having discharge outlets, one outlet being located to deliver at a pressure less than the delivery pressure of the other, a first conduit leading from the outlet of lower pressure to a point of delivery, a pressure tank, a second conduit connecting said tank with the outlet of higher pressure, a valve in the first conduit, and a control member in the second conduit responsive to flow of fluid toward said tank for opening the second conduit, said control member being connected with said valve for operating the valve in a closing direction during fluid flow toward said tank.

3. In a pumping system, a tank for storing fluid at a predetermined desired pressure, a pumping unit having a fluid outlet, a conduit connecting said fluid outlet with said tank, a flow responsive member disposed in said conduit movable to open the conduit in response to fluid flow toward said tank during periods of pump operation crating said valve in a closing direction upon member movement in an opening direction, whereby fluid flow in said last mentioned conduit is reduced during fluid flow toward said tank to restore the predetermined tank pressure.

4. In a pumping system as defined in claim 3, and in which said flow responsive member comprises an element displaceable by its own weight in a direction to effect a closure of the tank conduit for retaining the fluid delivered to said tank at substantially the predetermined pressure desired.

5. In a pumping system as defined in claim 3, and further including a check valve in said tank connected conduit for effecting a positive closure of the conduit against return flow of fluid from the tank upon attainment of the predetermined tank pressure.

6. In a pumping system, a pumping unit having two pumping stages, each stage being adapted to deliver at a different pressure, a tank adapted to store fluid at a predetermined pressure, a conduit connecting said tank with the delivery from one pumping stage, a control member disposed in said conduit to be responsive to fluid flow toward said tank for opening the conduit during pumping operation to supply the fluid therein at the predetermined pressure, a conduit leading from the other pumping stage to a point of delivery, a valve in said last mentioned conduit, and an operating connection between said valve and control member, whereby said valve is moved in a conduit closing direction upon control member movement in an opening direction such that the fluid pumped by said pumping unit is predominately directed toward said tank.

7. In a pumping system as defined in claim 6, and further including a check valve in said first mentioned conduit between said tank and the location of said con trol member, said check valve effecting a positive closing of the conduit under tank pressure influence to prevent loss of tank pressure during non-operating periods of said pumping unit.

8. In a pumping system for supplying fluid to a domestic supply tank and for irrigation purposes, a motor operated pumping unit having a high pressure fluid outlet and a low pressure fluid outlet, a conduit connected between said high pressure outlet and the tank, an electrical current supply circuit connected with said motor operated pumping unit, a pressure operated switch in said circuit and being connected into said pumping system so as to be responsive to predetermined pressure conditions in the tank for determining operating periods of the pumping unit, a check valve in said tank conduit for preventing tank depletion through the pump, during quiescent periods of said pumping unit, a conduit connected into said low pressure outlet and directing fluid for irrigation purposes, a valve in said latter conduit for regulating the flow of fluid during operating periods of the pumping unit, a switch and electrical circuit connections in shunt of said pressure switch for effecting a continuous period of pump operation, and a member disposed in said tank conduit for movement out of the path of fluid flowing toward said tank, said member being connected to said valve for regulating the valve in a direction to diminish fluid flow in said low pressure conduit during periods when draw-down of fluid from the domestic supply tank effects a pressure drop suflicient to cause high pressure flow of fluid toward the tank.

9. A pumping system comprising: a motor operated pump unit; a tank; a tank supply conduit connected into said pump unit; an automatic pressure responsive switch in energization control of said motor operated pump unit and connected into said tank supply conduit for determining operating periods of said pump unit to supply said tank with fluid under a desired pressure; a fluid discharge conduit connected into said pump unit at a zone where pressure developed during operation thereof is less than the pressure of the fluid delivered to said tank; check valve means in said tank supply conduit effective during quiescent periods of said pump unit to prevent fluid flow communication from said tank to said discharge conduit through said pump unit; a manually operable valve in said discharge conduit for closing the same to the flow of fluid therethrough during operating period of said pump unit as determined by said automatic switch; a control device operatively disposed in and between said tank supply and discharge conduits for regulating the flow of fluid in said discharge conduit, when said manual valve is open during an operating period of said pump unit; said control device including a member in said supply conduit movable out of the path of fluid flow therein to an extent determined by the magnitude of the diflerence of pressure at said tank and the pressure developed by said pump unit, and a valve element in said discharge conduit operatively connected with said member and movable by and in accordance with member movement to increase fluid flow in said discharge conduit as the magnitude of said pressure diflerence is decreased,

10. A pumping system comprising a motor operated pump unit, a fluid storage tank a first conduit arranged to deliver fluid from said pump unit to said tank, said pump unit being capable of developing a desired pressure in said tank during its operation, an automatic pressure switch in energization control of said motor pump unit and connected into the system to respond to the attainment of the desired tank pressure for stopping operation of said pump unit, a fluid discharge conduit connected into said pump unit at a Zone where pressure developed during operating periods thereof is different from that pressure developed in said tank, a control device associated with the pump system, said control device including a valve element in said discharge conduit and a member connected thereto and disposed in said first conduit, said member being movably responsive to the force of fluid passing through said first conduit as it is delivered to said tank for urging said valve element in a closing direction for modulating the flow of fluid in said discharge conduit proportionately to the tank pressure against which said pumpunit operates, means in the pumping system for reducing the tank pressure to a value at which said automatic switch starts operation of said pump unit, and means for preventing communication of said tank and discharge conduit during non-operating periods of said pump unit.

11. In a pumping system, a motor operated pumping unit provided with a high pressure discharge port and a relatively lower pressure discharge port, a tank for the storage of fluid under pressure, a supply conduit connecting said tank and high pressure discharge port of Said pumping unit, an automatic pressure responsive switch connected into said supply conduit and in energization control of said motor operated pumping unit for starting pump operation in response to a condition of tank pressure less than the pressure of fluid at said high pressure discharge port and for stopping pump operation in response to the attainment of a predetermined tank pres- 8 sure greater than the pressure at said high pressure discharge port, a discharge conduit leading from said pump discharge port of lower pressure, a shut-off valve in said latter conduit which, when closed, constrains pump dis charge toward said tank for establishing the predetermined tank pressure, a control device connected between said conduits and including a control valve in said discharge conduit and a member in said supply conduit connected to said control valve and operatively arranged to move in response to flow of fluid toward said tank for urging said control valve in a closing direction, said control device acting automatically to modulate the flow of fluid through said discharge conduit when said shut-off valve is open, so that fluid flowing past said control valve increases as the pressure in said tank approaches the pressure of fluid at said high pressure discharge port, and a manual valve in said supply conduit for dropping tank pressure to the pressure value at which said automatic pressure switch responds to start pump operation, whereby said pumping unit is rendered substantially continuously operative to deliver fluid at said discharge conduit when said shut-off valve is open.

12. In a pumping system, a pump having two discharge outlets, a first conduit connected to one of said outlets, a

1 second conduit connected to the other of said outlets, a

valve in said second conduit controlling flow of fluid therethrough, a control member disposed in said first conduit to control communication through said first conduit, said member being movable in one direction to open communication through said first conduit in response to pressure created in said first conduit by the flow of fluid therethrough, and means connecting said valve and member so that movement of said member in said one direction will etfect movement of said valve in said second conduit to decrease the flow of fluid in said second conduit.

13. In a pumping system, a pump having two discharge outlets, a first conduit connected to one of said outlets, a second conduit connected to the other outlet, a valve in said second conduit movable therein to modulate the flow of fluid through said second conduit, said valve being movable toward an open position by gravity, a control member in said first conduit adapted to control communication through said first conduit, said control mem- 45, her being responsive to the pressure of fluid passing References Cited in the file of this patent UNITED STATES PATENTS 2,218,565 Vickers Oct. 22, 1940 2,280,626 Carpenter Apr. 21, 1942 2,286,173 Maxon June 9, 1942 2,315,656 Rhoda Apr. 6, 1943 2,344,958 Armstrong et al. Mar. 28, 194 2,440,371 Holley, Jr. Apr. 27, 1948 2,470,471 Carleton May 17, 1949 2,486,256 Buck Oct. 25, 1949

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