AU2007205757B2

AU2007205757B2 - A pump system and a priming system for a centrifugal pump

Info

Publication number: AU2007205757B2
Application number: AU2007205757A
Authority: AU
Inventors: Andrew Geue; Robert Gorell; Grant Mitchell
Original assignee: Quik Corp Pty Ltd
Current assignee: Quik Corp Pty Ltd
Priority date: 2006-09-22
Filing date: 2007-08-10
Publication date: 2013-10-17
Anticipated expiration: 2027-08-10
Also published as: AU2007205757A1

Abstract

A pump system for providing fluid at different pressures and different flow rates, the pump system comprising at least two dissimilar pumps and a single 5 engine to drive the pumps. H:\SherylM\Keep\Speci\P64232.SPEC.doc 14/08/07 2, 3o

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant: Quik Corp Pty Ltd Invention Title: A PUMP SYSTEM AND A PRIMING SYSTEM FOR A CENTRIFUGAL PUMP The following statement is a full description of this invention, including the best method of performing it known to Us: -2 A PUMP SYSTEM AND A PRIMING SYSTEM FOR A CENTRIFUGAL PUMP Field of the Invention 5 The present invention relates to a pump system for providing fluid at different pressures and different flow rates. The present invention also relates to a priming system for a centrifugal pump. 10 Summary of the Invention According to a first aspect of the present invention there is provided a pump system for providing fluid at different pressures and different flow rates, the pump system comprising at least two dissimilar pumps and a is single engine to drive the pumps, each of the pumps selectively operable and configured to enable the system to simultaneously provide separate fluid outputs from the system with different pressures and flow rates, wherein one of the pumps is a centrifugal pump and one of the 20 pumps is a positive displacement pump. In an embodiment, the system also comprises an engagement mechanism for selectively engaging and disengaging the pumps with the engine. In another embodiment, the system also comprises 25 a recirculation mechanism for recirculating fluid from the outlet of at least one of the pumps to its inlet. The recirculation mechanism operates when fluid output from the at least one pump is not required. When the system comprises the recirculation mechanism, it is not necessary 30 to have the engagement mechanism. The pump system may comprise more than two pumps, at least two of which are dissimilar. In an embodiment, the system comprises two pumps; a centrifugal pump and a positive displacement 35 pump. 4640061_1 (GHMatters) P62130.AU.1 - 3 In an embodiment, the positive displacement pump is a diaphragm pump or a piston pump, preferably, a diaphragm pump. In another embodiment, the system comprises three 5 pumps; a centrifugal pump, a diaphragm pump, and a piston pump. In the embodiment comprising the recirculation mechanism, the at least one pump for which the recirculation mechanism recirculates fluid is the 10 centrifugal pump. In an embodiment, a first pump of the at least two pumps outputs fluid at a high flow rate and low pressure. Preferably, this pump is a centrifugal pump. In an embodiment, the first pump operates at a 15 maximum of 3000-4000rpm. In this embodiment, the first pump outputs fluid at a maximum flow of 200-400 L/min, preferably approximately 100 L/min. In this embodiment, the first pump outputs fluid 20 at a maximum pressure of 50-150psi, preferably approximately 100psi. In an embodiment, a second pump outputs fluid at a low flow rate and high pressure. Preferably, the second pump is a positive displacement pump. 25 In an embodiment, the second pump operates at a maximum of 300-600rpm. In this embodiment, the second pump outputs fluid at a maximum flow of 20-70 L/min, preferably approximately 50 L/min. 30 In this embodiment, the second pump outputs fluid at a maximum pressure of 400-600psi, preferably approximately 500psi. In this embodiment, the second pump is a diaphragm pump. 35 In another embodiment the second pump operates at a maximum of 2000-3000rpm. In this embodiment, the second pump outputs fluid H:\SherylM\Keep\Speci\P64237.SPEC.doc 10/08/07 - 4 at a maximum flow of 15-30 L/min, preferably approximately 25 L/min. In this embodiment, the second pump outputs fluid at a maximum pressure of 3000-5000psi, preferably 5 approximately 4000psi. In this embodiment, the second pump is a piston pump. In an embodiment, the pump system also comprises a priming system for the first pump, when it is a 10 centrifugal pump, the priming system comprising the second pump, when it is a positive displacement pump, wherein, the fluid outlet from the second pump is connected to the fluid inlet to the first pump to enable the second pump to prime the first pump. 15 In an embodiment, the engagement mechanism comprises one clutch for each pump. In an embodiment, each clutch separately engage and disengage its respective pump with the engine. In an embodiment, the clutches each are any 20 suitable clutch apparatus including a mechanical clutch or an electro-magnetic clutch. Preferably, the clutches are all electro-magnetic clutches. In an embodiment, the engine is at least of a 25 size which enables its maximum power output to drive the at least two pumps simultaneously. The engine may be any suitable engine, such as an electric, petrol or diesel engine for example. The engine has an output shaft and the pumps have 30 input shafts. In an embodiment, the engagement mechanism engages the pumps to the engine by connecting the output shaft from the engine to the input shafts to the pumps. In an embodiment, during operation of the pump 35 system, the engine output shaft is rotating at all times. The engagement and disengagement of the pumps with the engine may or may not be controlled remotely. H:\SherylM\Keep\Speci\P64237.SPEC.doc 10/08/07 -5 In an embodiment, control of the engagement and disengagement of the pumps with the engine is provided by any suitable means. In an embodiment, the system also comprises at 5 least two intermediate shafts which connect the engine output shaft to each of the pump input shafts. In an embodiment, the clutches of the engagement mechanism are located on the intermediate shafts. In an embodiment, the system also comprises 10 gearing mechanisms between the engine and each of the at least two pumps. In an embodiment, the system also comprises gearing mechanisms between the engine output shaft and each of the pump input shafts. 15 In an embodiment, the system also comprises gearing mechanisms between the engine output shaft and each of the intermediate shafts. In an embodiment, the system also comprises gearing mechanisms between each of the intermediate shafts 20 and their respective pump input shafts. The gearing mechanisms may be any suitable gearing mechanism such as straight cut or helical gears, however, preferably they are chain or belt drives. In an embodiment, the pump system is fixed to the 25 ground or built into a vehicle, or in other embodiments is skid mounted or otherwise portable and hence readily loadable onto a utility vehicle or a truck for example. In an embodiment, the pump system also comprises a tank for storing fluid for the pumps to pump. 30 In another embodiment, the pumps are arranged to draw fluid from a source of fluid such as a dam or creek for example. In an embodiment, the pumps are arranged to receive fluid from the tank and pump it to separate 35 outlets. In an embodiment, the outlets from each of the pumps are connected to separate hoses. H:\SherylM\Keep\Speci\P64237.SPEC.doc 10/08/07 -6 In another embodiment, the outlets from each of the pumps are connected to hoses which are arranged with one inside the other. In this embodiment, the system is provided with a 5 switching mechanism which enables an operator carrying the hoses (with one inside the other) to readily switch between the different fluid outputs from the pumps. According to a second aspect of the present invention, there is provided a priming system for a 10 centrifugal pump, the priming system comprising a second pump, being a positive displacement pump, wherein, the fluid outlet from the second pump is connected to the fluid inlet to the centrifugal pump to enable the second pump to prime the centrifugal pump. 15 In an embodiment, the positive displacement pump is a diaphragm pump or a piston pump, preferably a diaphragm pump. In an embodiment, the priming system also comprises a pressure controller for monitoring the 20 pressure of the fluid at the outlet of the second pump. In an embodiment, the system also comprises a bypass conduit for returning fluid from the outlet of the second pump to a tank for storing fluid for the pumps to pump. 25 Preferably, this occurs when the pressure of the fluid exiting the second pump is too high. In an embodiment, the system also comprises a connection conduit between the outlet of the second pump and the inlet of the centrifugal pump. 30 In an embodiment, the system also comprises a valve on the connection conduit, the valve being openable to enable fluid to flow from the outlet of the second pump to the inlet of the centrifugal pump. In an embodiment, the system also comprises a 35 non-return valve on the connection conduit to prevent any back flow into the second pump. In an embodiment, the priming system also H:\SherylM\Keep\Speci\P64237.SPEC.doc 10/08/07 - 7 comprises a priming discharge conduit connected to the outlet of the centrifugal pump, the priming discharge conduit for discharging overflow from the centrifugal pump during priming of the pump. 5 In an embodiment, the priming system also comprises a valve on the priming discharge conduit which closable to stop fluid flowing through the priming discharge conduit once the centrifugal pump is primed. In an embodiment, the priming system also 10 comprises a valve on the inlet to the centrifugal pump from the tank and a centrifugal pump outlet valve which are openable to enable the centrifugal pump to pump fluid from the tank to a conduit such as a hose, connected to the outlet of the pump. 15 In an embodiment, the system also comprises a second pump outlet valve which is openable, to enable the centrifugal pump to pump fluid from the tank to a conduit such as a hose, connected to the outlet of the pump. The valves may be operated by solenoids or by any 20 other suitable mechanism. According to a third aspect of the present invention, there is provided a pump system according to the first aspect, wherein a first pump is a centrifugal pump, and a second pump is a positive displacement pump, 25 the system also comprising a priming system for priming the centrifugal pump according to the second aspect of the present invention. Brief Description of the Drawings 30 Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a schematic view of a pump system according to an embodiment of the present invention; 35 Figure 2 is an exploded diagrammatic view of the pump system of Figure 1; and Figure 3 is a schematic view of a priming system H:\SherylM\Keep\Speci\P6423 7 .SPEC.doc 10/08/07 - 8 for a centrifugal pump according to an embodiment of the present invention. 5 Detailed Description of Embodiments of the Invention Referring firstly to Figures 1 and 2, a pump system 10 for providing fluid at different pressures and different flow rates is shown. The pump system 10 comprises first and second dissimilar pumps 11, 12 and a 10 single engine 13 to drive the pumps 11, 12. The pumps 11, 12 may be dissimilar in type, size, power, drive speed, maximum output pressure, maximum output volumetric flow rate or any combination thereof. Preferably, however, the pumps 11, 12 are of a dissimilar 15 type. This enables the system 10 to output fluid with vastly different pressure and flow rate characteristics. The first pump 11 is a centrifugal pump. The second pump 12 is generally a positive displacement pump, such as a diaphragm pump or a piston pump. In a variation on the 20 embodiment shown in Figures 1 and 2, the pump system comprises three pumps; a centrifugal pump, a piston pump and a diaphragm pump. It is noted that this variation emphasises that the pump system 10 of the present system may comprise more than two pumps driven by the single 25 engine 13, at least two of which are dissimilar. The first centrifugal pump 11 outputs fluid at a high flow rate and low pressure. The first pump 11 typically operates at a maximum of 3000-4000rpm. The first pump 11 outputs fluid at a maximum flow of 200-400 L/min, 30 preferably approximately 100 L/min. The maximum pressure of the fluid outputted by the first pump 11 is 50-150psi, preferably approximately 100psi. The second pump 12 outputs fluid at a low flow rate and high pressure. If the second pump 12 is a 35 diaphragm pump then it typically operates at a maximum of 300-600rpm. In this embodiment, the second pump 12 outputs fluid at a maximum flow of 20-70 L/min, preferably H:\SherylM\Keep\Speci\P64 23 7.SPEC.dOC 10/08/07 - 9 approximately 50 L/min and at a maximum pressure of 400 600psi, preferably approximately 500psi. If the second pump 12 is a piston pump then it typically operates at a maximum of 2000-3000rpm. In this 5 embodiment, the second pump 12 outputs fluid at a maximum flow of 15-30 L/min, preferably approximately 25 L/min and at a maximum pressure of 3000-5000psi, preferably approximately 4000psi. Thus, the pump system 10 enables the simultaneous 10 output of fluid at high pressure and low volume and fluid at low pressure and high volume due to the characteristics of the two pumps 11, 12. The use of a single engine 13 to drive the pumps 11, 12 enables the pump system 10 to be more compact, lighter and less costly. The pump system 10 15 may be fixed to the ground or built into a vehicle, or alternatively may be skid mounted or otherwise portable and hence readily loadable onto a utility vehicle or a truck for example. A particularly suitable application for the pump 20 system 10 is in fire-fighting where water is required at high volume and low pressure to quickly reduce the heat of a fire and where water may also be required at high pressure and low volume for spotting small localised areas of fire or to produce a fine mist for compartment fire 25 fighting. Advantageously, the pump system 10 enables one fire fighter to provide the water at high volume and low pressure to reduce the heat of a fire, whilst simultaneously a second fire fighter can put out small localised areas of fire using the same pump system 10. 30 The system 10 also comprises an engagement mechanism 14 for selectively engaging and disengaging the pumps 11, 12 with the engine 13. The engagement mechanism 14 comprises first and second clutches 15 and 16 respectively, ie., one clutch per pump. The first clutch 35 15 may separately engage and disengage the first pump 11 with the engine 13. Similarly, the second clutch 16 may separately engage and disengage the second pump 12 with H:\SherylM\Keep\Speci\P64237.SPEC.doC 10/08/07 - 10 the engine. Thus, whilst the engine 13 is in operation, at any time, it may be driving none, one or all of the pumps 11, 12 simultaneously. Thus, the engine 13 is at least of a size which enables its maximum power output to drive the 5 pumps 11, 12. The engine 13 may be any suitable engine, such as an electric, petrol or diesel engine for example. The clutches 15, 16 may each be any suitable clutch apparatus including a mechanical clutch, however, preferably, the clutches 15, 16 are both electro-magnetic 10 clutches. Electro-magnetic clutches have the advantages of being low cost, compact and reliable. In a variation, the system 10 comprises a recirculation mechanism for recirculating fluid from the outlet of one of the pumps (preferably, the first 15 centrifugal pump 11) to its inlet. The recirculating mechanism operates (is engaged) when fluid output from the pump 11 is not required. In this embodiment, it is not necessary to have the engagement mechanism. The engine 13 has an output shaft 20 and the 20 pumps 11, 12 have input shafts 21, 22. The clutches 15, 16 engage the pumps 11, 12 to the engine 13 by connecting the output shaft 20 from the engine 13 to the input shafts 21, 22 to the pumps 11, 12. During operation of the pump system 10, the engine output shaft 20 is rotating at all 25 times. The pump input shafts 21, 22 will only rotate when engaged with the engine output shaft 20. The engagement and disengagement of the pumps 11, 12 with the engine 13 may or may not be controlled remotely, with the control being provided by any suitable means. 30 The system 10 may or may not also comprise intermediate shafts 23 as shown in the embodiment in Figures 1 and 2 which connect the engine output shaft 20 to the pump input shafts 21, 22. The clutches 15, 16 are located on the intermediate shafts 23. The intermediate 35 shafts 23 enable a ready split of the mechanical output from the output shaft 20. Furthermore, the intermediate shafts 23 enable the system 10 to also comprise gearing H:\Shery1M\Keep\Speci\P64237.SPEC.doc 10/08/07 - 11 mechanisms 24, 25 between the engine output shaft 20 and the intermediate shafts 23 as well as gearing mechanisms 26, 27 between the intermediate shafts 23 and the pump input shafts 21, 22. This enables smaller gearing 5 mechanisms to be provided between the engine 13 and the pumps 11, 12. The gearing mechanisms 24, 25, 26, and 27 increase or decrease the speed of rotation as required from the engine output shaft 20 to the pump input shafts 10 21, 22. The gearing mechanisms 24, 25, 26, 27 may be any suitable gearing mechanism such as straight cut or helical gears, however, preferably they are chain or belt drives. The chain or belt drives enable a multiple variation of the gearing ratios between the engine 13 and the pumps 11, 15 12. The pump system 10 also comprises a tank 30 for storing fluid for the pumps 11, 12 to pump. The pumps 11, 12 may be arranged to also draw fluid from an alternative source of fluid such as a dam or creek, for example. The 20 pumps 11, 12 receive fluid from the tank 30 and pump it to separate outlets 31, 32. The outlets 31, 32 from the pumps 11, 12 are connected to separate hoses. In an alternative embodiment, the outlets 31, 32 are connected to hoses which are arranged with one inside the other. In this 25 embodiment, the system is provided with a switching mechanism which enables an operator carrying the hoses (with one inside the other) to readily switch between the different fluid outputs from the pumps 11, 12. Referring now to Figure 3, a priming system 40 30 for a centrifugal pump is shown. The centrifugal pump is the first pump 11. The priming system 40 comprises the second pump 12, being a positive displacement pump. The fluid outlet 32 from the second pump 12 is connected to the fluid inlet to the first pump 11 to enable the second 35 pump 12 to prime the first pump 11. The priming system 40 is suitable for use in the pump system 10 described above. The second, positive displacement pump 12 is a diaphragm H:\SherylM\Keep\Speci\P64237.SPEC.doc 10/08/07 - 12 pump or a piston pump, preferably a diaphragm pump. The priming system 40 also comprises a pressure controller 41 for monitoring the pressure of the fluid at the outlet 32 of the second pump 12. The system 40 also 5 comprises a bypass conduit 42 for returning fluid to the tank 30 from the outlet 32 of the second pump 12 if the pressure of the fluid exiting the second pump 12 is too high. To prime the centrifugal pump 11, the second pump 12 must be bypassing fluid to the tank 30 through the bypass 10 conduit 42. A valve 43 on a connection conduit 44 between the outlet 32 of the second pump 12 and the inlet of the first pump 11 is subsequently opened, enabling fluid to enter and fill the first pump 11. A non-return valve 45 on the connection conduit 44 prevents any back flow into the 15 second pump 12. Importantly, the impellor of the first centrifugal pump 11 is not rotating whilst being filled with fluid. The priming system 40 also comprises a priming discharge conduit 46 connected to the outlet 31 of the 20 centrifugal pump 11 for discharging overflow from the centrifugal pump 11 during priming of the pump. Once the centrifugal pump 11 has been flooded, fluid exits the pump 11 through the outlet 31 and through the priming discharge conduit 46, indicating that the centrifugal pump 11 is 25 primed. When this occurs, a valve 47 on the priming discharge conduit 46 and the valve 43 on the connection conduit 44 are closed. With the centrifugal pump 11 primed, it is ready to pump fluid from the tank 30 to a conduit such as a hose, which is connected to the outlet 30 31 as required. In order to do so a valve 48 on the inlet to the pump 11 from the tank 30 and a first pump outlet valve 49 are opened. Similarly, a second pump outlet valve 50 may be opened, separately, to enable the second pump 12 to pump fluid from the tank 30 to a conduit such as a 35 hose, connected to the outlet 32. During priming of the centrifugal pump 11, the outlet valves 49, 50 are closed. The valves 43, 47, 48, 49 and 50 may be operated by H:\SherylM\Keep\Speci\P54237.SPEC.doc 10/08/0' - 13 solenoids or by any other suitable mechanism. The priming system 40 is also shown comprising a suction conduit 51, which enables the pumps 11, 12 to draw fluid from an alternative source to the tank 30 such as a 5 dam or creek for example. In the claims which follows and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as 10 "comprises" or "comprising" is used in an inclusive sense, ie. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. H:\SherylM\Keep\Speci\P64237.SPEC.doc 10/08/07

Claims

1. A pump system for providing fluid at different pressures and different flow rates, the pump system comprising at least two dissimilar pumps and a 5 single engine to drive the pumps, each of the pumps selectively operable and configured to enable the system to simultaneously provide separate fluid outputs from the system with different pressures and flow rates wherein one of the pumps is a centrifugal pump and one of the pumps is 10 a positive displacement pump.

2. A pump system as claimed in claim 1, wherein the positive displacement pump is a diaphragm pump or piston pump. is

3. A pump system as claimed in any one of the preceding claims, wherein a first pump of the at least two pumps outputs fluid at a high flow rate and low pressure and a second pump outputs fluid at a low flow rate and 20 high pressure.

4. A pump system as claimed in claim 3, wherein the first pump operates at a maximum of 3000 to 4000rpm. 25

5. A pump system as claimed in either claim 3 or claim 5 wherein the first pump outputs fluid at a maximum flow of 200 to 400 litres per minute and a maximum pressure 50 to 150 psi. 30

6. A pump system as claimed in any one of claims 3 to 5 , wherein the second pump operates at a maximum of 300 to 600rpm. 35

7. A pump system as claimed in any one of claims 3 to 6, wherein the second pump outputs fluid at a maximum flow of 20 to 70 litres per minute and at a 4640061_1 (GHMatters) P62130.AU.1 - 15 maximum pressure of 400 to 600 psi.

8. A pump system as claimed in any one of claims 3 to 5, wherein the second pump operates at a 5 maximum of 2000 to 3000rpm.

9. A pump system as claimed in any one of claims 3 to 6, wherein the second pump outputs fluid at a maximum flow of 15 to 30 litres per minute and at a 10 maximum pressure of 3000 to 5000 psi.

10. A pump system as claimed in any one of the preceding claims, wherein the system also comprises an engagement mechanism for selectively engaging and 15 disengaging pumps with the engine.

11. A pump system as claimed in claim 10, wherein the engagement mechanism comprises one clutch for each pump. 20

12. A pump system as claimed in either claims 10 or 11, wherein the engine has an output shaft, the pumps have input shafts and the engagement mechanism, engages the pumps of the engine by connecting the output 25 shaft from the engine to the input shafts to the pumps and the system also comprises at least two intermediate shafts which connect the engine output shaft to each of the pump input shafts. 30

13. A pump system as claimed in any one of the preceding claims, wherein the system also comprises gearing mechanisms between the engine and each of the at least two pumps. 35

14. A pump system as claimed in any one of the preceding claims, the system also comprising a recirculation mechanism for recirculating fluid from the 46400611 (GHMatters) P62130.AU.1 - 16 outlet of at least one of the pumps to its inlet.

15. A pump system as claimed in any one of the preceding claims, wherein the outlets from each of the 5 pumps are connected to separate hoses.

16. A pump system as claimed in any one of the preceding claims, wherein the outlets from each of the pumps are connected to hoses which are arranged with one 10 inside the other.

17. A pump system as claimed in any one of the preceding claims, wherein one of the dissimilar pumps is a centrifugal pump and a priming system for the centrifugal is pump, the priming system comprising a positive displacement pump, wherein the fluid outlet from the positive displacement pump is connected to the fluid inlet to the centrifugal pump to enable the positive displacement pump to prime the centrifugal pump. 20

18. A pump system as claimed in claim 17, wherein the priming system also comprises a pressure controller for monitoring the pressure of the fluid at the outlet of the positive displacement pump. 25

19. A pump system as claimed in any one of claims 17 or 18 , wherein the system also comprises a bypass conduit for returning fluid from the outlet of the positive displacement pump to a tank for storing fluid for 30 the pumps to pump.

20. A pump system as claimed in any one of claims 17 to 19, the priming system also comprising a priming discharge conduit connected to the outlet of the 35 centrifugal pump, the priming discharge conduit for discharging overflow from the centrifugal pump during priming of the pump. 4640061_1 (GHMatters) P62130.AU.1 - 17

21. A pump system as substantially described herein with reference to the accompanying Figures. 4640061_1 (GHMatters) P62130.AU.1