AU609427B2 - Liquid pump - Google Patents

Description

applicant or Australian attorney I u (Signature) THE COMMISSIONER OF PATENTS This form must be accompanied by either a provisional specification (Form 9 and true copy) or by a complete specification (Form 10 and true copy).

II r 60 9 427 COMMONWEALTH OF AUSTRALIA Patents Act 1952 COMPLETE SPECIFICATION (Original) FOR OFFICE USE Application Number: PH08771 Class Lodged: 3 November, 1986 Int. Class Complete Specification Lodged: 3 November, 1987 Accepted: Published: Priority: Cl a c acc a it at a GIlt a ic cCC a a cE a a a a This document contains the amendments made under Section 49 and is correct for printing Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: ALAN KEITH BROWN Address of Applicant: of P 0 Box 28, Bruce Rock, in the State of Western Australia, Commonwealth of Australia.

Actual Inventor: ALAN KEITH BROWN Address for Service:- Wray Associates Primary Industry House 239 Adelaide Terrace Perth Western Australia 6000.

Complete Specification for the invention entitled: "Liquid Pump" The following statement is a full description of this invention, including the best method of performing it known to me:- -1 t. 1 2 THIS INVENTION relates to liquid pumps. It is particularly applicable to submersible pumps for pumping water from wells and bores.

In one aspect of the invention there is provided a liquid pump comprising an elongate housing defined by side wall means, a top wall and a bottom wall; a pumping chamber defined within the housing; a liquid inlet for entry of liquid into said chamber; a first one-way valve means adapted to allow liquid to pass into said pumping chamber "0 via said liquid inlet but preventing return flow of said 0 0000 liquid; a liquid outlet means having an outlet opening o communicating with said pumping chamber; a second one-way Ooo valve associated with said liquid outlet moans and adapted "0 to allow liquid to be discharged-from said pumping chamber 0o"0 via said liquid outlet means but preventing return flow to 0 0 00 00 oo said chamber; an inlet means extending through said housing and having an inlet opening for selectively supplying compressed air to said chamber; a vent means for o 0o selectively venting air from said pumping chamber; 0characterised in that said liquid inlet comprises an inlet o oo 000 tube extending upwardly into the pumping chamber to o S terminate at an outlet end located above the bottom wall and above the outlet opening of the liquid outlet means and said first one-way valve comprising a foot valve comprising a ball and a valve seat for sealing engaging said ball.

t C Preferably said first one-way valve is provided at the upper end of said inlet tube.

Preferably said side wall means defined a substantially cylindrical wall thereby making the liquid pump well suited for downhole bore use.

-3- Preferably said valve seat is defined by the upper end of said inlet pipe.

Preferably said liquid pump further comprises a low liquid level sensing means, a high liquid level sensing means, and electrical control means, and a three-way valve means, wherein upon a predetermined low liquid level being reached in said chamber said low liquid levels sensing means produces a signal to said electrical control means which in turn alters the state of said three-way valve o .means to allow venting of the air from said chamber via "Off said venting means and simultaneously deactivates said air 0o inlet means, and upon a predetermined high liquid level C being reached in said chamber said high liquid level €C sensing means produces a signal to said electrical control means which in turn alters the state of said three-way o o. valve means to allow compressed air to enter said chamber via said air inlet means and simultaneously deactivates said vent means.

o o ~Preferably said ball is of a relatively soft material and 09 said matching valve seat is of a relatively hard material, S said ball being adapted for free rotation with respect to 0 C said valve seat.

t The invention will be better understood by reference to C CCC the following description of one specific embodiment thereof as shown in the accompanying drawings in which:- Fig. 1 is a schematic view of part of a water pumping installation incorporating a pump according to the embodiment; and Ukai 1c- i: 4 Fig. 2 is a partially sectioned view of the pump according to the embodiment.

The embodiment shown in the drawings is directed to a submersible water pump 10 intended for use in bores and wells. The pump is serviced by a compressed air delivery/vent line 7 has an outlet line 9 taking the water to the surface.

Referring to Fig. 2, the pump according to the embodiment includes a housing 11 having a bottom wall 17, cylindrical side wall 13, a top wall 15, and a pump chamber 19 defined within the housing.

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A water intake opening 21 is located in the bottom wall 17 of the housing 11. The intake opening 21 includes a tube which extends upwardly into the pump chamber to terminate at an outlet end 26 located above the bottom of the pump chamber. The opening 21 is fitted with a one-way valve means in the form of a foot valve 23 mounted on the tube 25 at the outlet end 26. The foot valve allows water to enter the pump chamber but prevents the flow of water back through the inlet 21.

The foot valve 23 comprises a ball valve member 39, and a valve seat 41 which is formed integrally with tube 25 at the outlet end 26 thereof. A retaining cage 43 is provided to retain the ball valve r.mber in the vicinity of the outlet opening while allowing it to rotate freely and move into and out of engagement with the valve seat.

A tube 27 extends through the top wall 15 and opens at its lower end 29 into the pump chamber 19. The tube 27 is sealed against the top wall 15 to prevent the loss of air pressure within the pumping chamber.

II-- The tube 27 serves two functions. One of the functions of the tube is to selectively act as a delivery line for supplying the compressed air to the pumping chamber. The other functions of the tube is to selectively act as a vent means for venting the pumping chamber 19 to atmosphere.

The upper end of the tube 27 is connected to a three-way control valve (not shown). In one mode, the control valve operates the air delivery function of the tube. In the second mode the control valve operates the venting CC function of the tube.

ter A liquid outlet means in the form of outlet tube 29 having an outlet opening 31 at its lower end, is provided within 'i'r the housing 13. The outlet opening 31 communicates with C the pumping chamber 19 and is located below the outlet end 26 of the water intake opening 21. The outlet tube passes through the top wall 15 and has a second one-way valve, in the form of'-ball valve 33, positioned at its upper end.* Ball valve 33 will- allow water to pass out of the pumping chamber but will prevent it from flowing back into it.

tc A low liquid sensing means in ihe form of probe 35, and a high liquid level sensing means in the form of probe 37 are provided within the pumping chamber 19. These probes will sense the passing of the water level passed the lower ends of the respective probes and a signal will be generated.

In operation down a bore hole or well, the liquid pump will receive water into the pump chamber through the intake opening 21. This water may, and very often does, contain silt and/or other foreign matter. The water level will rise within the pump chamber until it passes the high level probe 37. This probe sends a signal to a control -6 unit (not shown) which activates the three-way control valve (not shown) to assume its first mode whereby.

compressed air supply is brought into communication with tube 27. Compressed air then forces the liquid within the housing to flow through outlet opening 31 and up outlet tube 29. The ball valve 23 prevents back-flow of water through the intake 21.

Upon the liquid level dropping below the lower end of probe 35 a signal is sent to the control unit and the three-way valve assumes its second mode so that the tube 27 now communicates with atmosphere and therefor acts as a vent. Simultaneously, the three-way valve acts to close cq the communication between the tube 27 and the compressed air supply. The ball valve 33 prevents water from flowing Q back into the pumping chamber.

The liquid level now begins to rise, the air trapped in the pump chamber being expelled by the rising water level through the vent until the level passes the end of the no, upper probe 37 and the previous described process is repeated.

U U U° During the above described pumping sequence it will be S appreciated that silt and other foreign matter entrained in the bore water will enter the pump chamber along with the water. This foreign matter if heavier than water may Ssettle at the base of the foot valve 23 in the region However, due to the fact that outlet opening 31 is lower than the outlet end 26 of the intake opening 21 the flow of water out of the pumping chamber is directed towards region 50 thereby causing at least some of 'the foreign matter to be entrained in the flowing water and thus expelling this foreign matter out through outlet tube 29.

2 2 -I-ra; :I u*ar--i; L 7 In the worst scenario the foreign matter may build up in the region 50 until it approaches the height of outlet opening 31. However, the flow of water through outlet tube 29 will have a self cleansing action and will prevent a blocking of the outlet. Therefore, the height of the build-up of the foreign matter will be limited to being below the outlet opening which in this embodiment, in turn, is below the ball valve 23. It follows then that the foreign matter will be prevented from fouling the ball valve 23, and the desired result is achieved.

It should be appreciated that a pump according to the invention may have applications other than merely pumping water from wells and bores. In this connection, the pump may be constructed entirely of plastic materials thereby I to make it particularly suitable for pumping corrosive liquids.

It should also be appreciated that the scope of the invention is not limited to the scope of the embodiment described.

Ccci In particular it is envisaged that an arrangement where a foot valve in the form of a ball valve, similar to bore valve 23 in the previous embodiment, is actually positioned below the outlet opening but a suitable wall means of a diameter slightl' larger than the ball is extended upward from the valve seat of the bore valve and terminates at a height which is above the outlet opening of the pump.

Claims (6)

1. A liquid pump comprising an elongate housing defined by side wall means, a top wall and a bottom wall; a pumping chamber defined within the housing; a liquid inlet for entry of liquid into said chamber; a first one-way valve means adapted to allow liquid to pass into said pumping chamber via said liquid inlet but preventing return flow of said liquid; a liquid outlet means having Vran outlet opening communicating with said pumping chamber; a second one-way valve associated with said liquid outlet ~means and adapted to allow liquid to be discharged from said pumping chamber via said liquid outlet means but preventing return flow to said chamber; an inlet means extending through said housing and having an inlet opening for selectively supplying compressed air to said chamber; i 1 a vent means for selectively venting air from said pumping chamber; characterised in that said liquid inlet comprises an inlet tube extending upwardly into the pumping chamber to terminate at an outlet end located above the bottom wall and above the outlet opening of the liquid outlet means and said first one-way valve comprising a foot valve comprising a ball and a valve seat for sealing engaging said ball. i It

2. A liquid pump according to claim 1 wherein said first one-way valve is provided at the upper end of said inlet tube.

3. A liquid pump according to claim 2 wherein said valve seat is defined by the upper end of said inlet tube.

4. A liquid pump according to any of the preceding claims comprising a low liquid level sensing means, a high liquid level sensing means, and electrical control means, and a three-way valve means, wherein upon a predetermined low -9 liquid level being reached in said chamber said low liquid levels sensing means produces a signal to said electrical control means which in turn alters the state of said three-way valve means to allow venting of the air from said chamber via said venting means and simultaneously deactivates said air inlet means, and upon a predetermined high liquid level being reached in said chamber said high liquid level sensing means produces a signal to said electrical control means which in turn alters the state of said three-way valve means to allow compressed air to enter said chamber via said air inlet means and simultaneously deactivates said vent means. 0 E

5. A liquid pump according to any of the preceding O't claims wherein said ball is of a relatively soft material and said matching valve seat is of a relatively hard 0,0 material, said ball being adapted for free rotation with respect to said valve'seat.

6. A liquid pump substantially as herein described, *o-o with reference to Figs. 1 and 2 of the accompanying Sdrawings. DATED this THIRTIETH day of JANUARY 1991 1 "c *ALAN KEITH BROWN I0 t, nApplicant Sc WRAY ASSOCIATES Perth, Western Australia Patent Attorneys for Applicant