PUMP SYSTEM

Abstract

A pump system is presented having a pump with a generally cylindrical pump housing that is arranged with a liquid inlet in one end and a liquid outlet in a second end. A tubular membrane is arranged inside the pump housing and a first passage is arranged in the vicinity of the liquid inlet for introducing pressurized fluid between the membrane and the housing. A second passage arranged in the vicinity of said liquid outlet for releasing said pressurized fluid where the membrane is arranged with an elasticity providing a local radial compression and an annular fluid compartment when a pulse of pressurized fluid is entered through the first passage. The annular fluid compartment travels along the housing bringing a volume of liquid with it. An expansion vessel can be operably attached to the liquid outlet for reducing pressure changes in the liquid caused by the action of the pulse of pressurized fluid.

Claims

1-14 (canceled)

15. A pump system comprising: a pump having a generally cylindrical pump housing, where the pump housing is arranged with a liquid inlet in one end and a liquid outlet in a second end; a tubular membrane arranged inside the pump housing; a first passage arranged in the vicinity of the liquid inlet for introducing pressurized fluid between the membrane and the housing; and a second passage arranged in the vicinity of the liquid outlet for releasing the pressurized fluid, wherein the membrane is arranged with an elasticity providing a local radial compression and a ring-shaped fluid compartment when a pulse of pressurized fluid is entered through the first passage, wherein the fluid compartment travels along the housing bringing a volume of liquid with it, wherein the pump system further comprises an expansion vessel operably attached to the liquid outlet for reducing pressure changes in the liquid caused by the action of the pulse of pressurized fluid.

16. The pump system according to claim 15, wherein the pump during operation is positioned with the inlet oriented generally vertically downwards and with the outlet oriented generally vertically upwards.

17. The pump system according to claim 16, further comprising a conduit attached to the liquid outlet and being oriented generally vertically for creating a liquid column.

18. The pump system according to claim 17, wherein the length of the conduit is chosen such that a liquid column is created having a weight creating a pressure on the membrane ensuring a tight seal between the membrane and an inner surface of the pump housing.

19. The pump system according to claim 17, wherein an upper end of the conduit is arranged with a branch, wherein the expansion vessel is attached to one branch and a second branch constitutes an outlet for the liquid.

20. The pump system according to claim 15, further comprising a compressor operably connected to a pulse generator for providing pulses of pressurized fluid to the pump housing.

21. The pump system according to claim 20, wherein the pulse generator is a pressure valve that opens above a certain pressure threshold and closes below the pressure threshold.

22. The pump system according to claim 20, further comprising a power generator operably connected to the compressor, capable of energizing the compressor.

23. The pump system according to claim 22, where the power generator comprises one or several of photovoltaic panels, wind turbines, water turbines.

24. The pump system according to claim 22, wherein the power generator comprises at least one battery operably connected to the compressor.

25. The pump system according to claim 23, wherein one of the one or several of photovoltaic panels, wind turbines, water turbines are arranged to charge the at least one battery.

26. The pump system according to claim 15, further comprising a check valve in liquid communication with the inlet passage of the pump housing.

27. The pump system according to claim 26, further comprising a filter unit arranged before the check valve relative to a direction of flow of the liquid.

28. The pump system according to claim 26, wherein the check valve comprises a generally tubular body provided with a number of passages, a generally tubular flexible membrane arranged coaxial with and inside the body having one end of the tubular membrane fixedly attached to the body.

29. The pump system according to claim 15, wherein the second passage is arranged with a conduit of such a length as to ensure that its free end is above the liquid level when placed in the liquid.

30. The pump system according to claim 15, wherein the pressurised fluid is pressurised ambient air.

31. The pump system according to claim 15, further comprising a buoyancy element.

32. The pump system according to claim 15, further comprising anchoring rods adopted to be attached to a lake, pond or similar larger water areas bottom.

33. The pump system according to claim 15, further comprising conduits on inlet and outlet sides of the pump are arranged as modules with fixed lengths that are inter-connectable.

34. A pump comprising: a generally cylindrical pump housing, where the housing is arranged with a liquid inlet in one end and a liquid outlet in a second end; a tubular flexible membrane arranged inside the pump housing; a first passage arranged in the vicinity of the liquid inlet for introducing pressurized fluid between the membrane and the housing; and a second passage arranged in the vicinity of the liquid outlet for releasing the pressurized fluid, where the membrane has an elasticity providing a local radial compression and forming a ring-shaped fluid compartment when a pulse of pressurized fluid is entered through the first passage, wherein the fluid compartment is able to travel along the housing bringing a volume of liquid with it.

35. The pump according to claim 34, wherein the tubular flexible membrane is made of one of a rubber hose and plastic having the required properties and has a shape and dimension so as to contact at least a major part of the inner surface of the housing when placed inside the housing.

36. The pump according to claim 34, wherein the ends of the flexible membrane are attached to the housing at the inlet and outlet passages by appropriate attachment elements.

37. The pump according to claim 34, wherein the housing is further arranged with two passages, where one passage connected to the pressure source is situated closer to the inlet than the other passage.

38. The pump according to claim 34, wherein two passages are preferably arranged on the same side of the pump housing when viewed in a circumferential direction, and each passage is arranged with suitable attachment elements.

39. The pump according to claim 34, wherein the pressurised fluid is pulsated pressurised ambient air.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0021] In the following detailed description of the disclosure, reference will be made to the accompanying drawings, of which

[0022] FIG. 1 is a schematic view of a pump system according to the disclosure,

[0023] FIG. 2 is a cross-sectional view of a pump comprised in the pump system of FIG. 1,

[0024] FIG. 3 is a cross-sectional view of a check valve that may be used with the pump system of FIG. 1, and

[0025] FIG. 4 is a cross-sectional view of the working principle of the pump of FIG. 2.

DETAILED DETAILED DESCRIPTION

[0026] The pump system that is described below comprises a pump 10 having generally tubular elongated pump housing 12 provided with passages at each end thereof, one inlet passage 14 and one outlet passage 16. The passages are arranged with suitable attachment elements for connecting suitable conduits to each passage. The attachment elements may comprise e.g. threads, bayonet fittings, quick couplings of garden hose type, just to mention a few.

[0027] The interior of the housing is arranged with a generally tubular flexible element or membrane 18 such as e.g. a rubber hose. It is however to be understood that other types of material, such as plastic, having the required properties may be utilized. The flexible element 18 has a shape and dimension so as to contact at least a major part of the inner surface of the housing 12 when placed inside the housing 12. The ends of the flexible element 18 are attached to the housing 12 at the inlet and outlet passages by appropriate attachment elements 20.

[0028] The housing 12 is further arranged with two passages 22, 24 on its side surface. Preferably the passages 22, 24 are arranged on the same side as seen in a circumferential direction, but this is not a requirement. An important factor is however that one passage 22 is closer to the inlet 14 than the other passage 24. Each passage is arranged with suitable attachment elements such as for example threads. The passage 22 closer to the inlet 14 is connected via a suitable conduit 23 to a suitable pressure source 26 that is capable of providing pulsated pressurised air, as will be explained. For instance, a compressor 26 may be used for creating pressurized air and a pulse generator 25 may be arranged between the compressor 26 and the passage 22 for the air. The pulse generator may for example be a pressure valve that opens above a certain pressure threshold and closes below said pressure threshold. However, there are many other types of pulse generators on the market that may be used, and which are known to the skilled person.

[0029] The compressor 26 is connected to a suitable power source which may be selected from various alternatives, depending on the pump application and on the available power. It may either be connected to a conventional mains power system, to photovoltaic panels 27a, batteries 27b and/or water or air driven power generators 27c, 27d respectively. If batteries are utilized, other power generators may be used for charging the batteries.

[0030] The outlet passage 24 for the air is arranged with a conduit 28 of a length such that it is ascertained that the outlet of the conduit 28 is well above the liquid level LL in which the pump is submersed. Preferably the conduit 28 is of a non-flexible material and should be dimensioned such that flow-resistance for the passing air is as low as possible.

[0031] The inlet 14 of the housing 12 is preferably attached to a check valve 30, either directly or via a suitable conduit 31. The check valve 30 may further be provided with a filter 32 for preventing objects and larger particles from entering the pump 10. The filter 32 may either be an ordinary mesh filter, possibly integrated with the check valve 30, or it may comprise a combined valve and filter where valve members are placed in the orifices of the filter 32. Since the pump 10 of the present disclosure can handle rather large objects having dimensions somewhat smaller than the inner diameter of the pump without being damaged, as will be described below, the orifices may be rather large.

[0032] FIG. 3 shows one type of check valve having a generally tubular body 34 with one end in liquid communication with the pump 10. The other end is closed off by a lid or wall 36. Around the circumference of the body a number of passages 38 are arranged. Inside the body 34 a generally tube-shaped flexible membrane 40 is arranged having a shape and dimension so as to be in contact with the inner surface of the body 34. When the interior of the valve 30 is filled with liquid and the pump 10 is not active, the column of liquid in the pump system that is arranged above the valve 30 as seen in a vertical direction will press the membrane against the inner surface of the body, effectively closing the passages as seen in FIG. 3a. On the other hand, if the pump 10 is active and liquid is drawn by the pump 10, the flexible membrane 40 will flex inwards due to the suction action of the pump 10, FIG. 3b, thereby opening the passages 38 so that liquid may flow. The size of the passages 38 is chosen such that larger objects are prevented from entering.

[0033] The outlet passage 16 of the pump 10 is arranged with a conduit 42 of a certain length. The length is chosen such that a column of liquid of a certain weight is obtained. The weight is chosen such that it is ascertained that the membrane 18 is pressed against the inner surface of the pump housing 12. At the upper end of the conduit 42, a branch 44 may be arranged, such as a T-shaped connection. An expansion vessel 46 is attached to one of the connections, preferably the vertical connection as seen in FIG. 1. The function of the expansion vessel 46 is to handle the pressure peaks that are generated when the pump 10 is working in order to smooth out the pressure peaks against the pressure that is formed in the pump system during operation.

[0034] Regarding the conduits 31 and 42 on both sides of the pump, it might be advantageous to arrange these as modules with fixed lengths that are inter-connectable. In this manner, the pump may be modified to have a longer inlet for instance if the pump is to be placed in a drilled well. On the other hand, it might in some instances be advantageous to have the outlet longer in order to create a higher water column. Regarding drilled wells, the dimensions of the pump, including the attachments of the passages 22, 24 and the conduits, in the transversal direction may be chosen so as to fit in tubes of drilled wells.

[0035] If the pump is to be placed in a lake, pond or similar larger water areas, it might be arranged with some type of buoyancy element 60 such as a plate of floating material that is attached to the pump. The buoyancy element 60 may further be arranged with attachment functions such as through-holes, through which anchoring rods 62 may be placed and in turn attached to the lake bottom LB. attachment functions may also or instead include ropes and the like for holding the pump in place. The buoyancy element 60 may further function as a lid if the pump is used in a drilled or dug well.

[0036] The pump system is intended to function as follows. The pump 10 is placed in the liquid to be pumped, preferably vertically with its inlet 14 downwards and its outlet 16 upwards. The pump 10 is placed at such a depth that the outlet passage of the conduit 28 for the compressed air is well above the liquid level. The compressor 26 is then activated whereby it delivers compressed air. In that regard, the compressor 26 might be driven by photovoltaic panels, providing an inexpensive operation in places where there is a lack of electric power. A pulse generator connected to the compressor generates a series of pulses of compressed air. Each pulse of compressed air presses the membrane 18 to be locally radially compressed, FIG. 4a. The pulse of air thus creates an annular fluid compartment 50 that is moving upwards between the membrane 18 and the housing 12 towards the outlet.

[0037] In order to ensure a pumping effect, i.e. creating the local annular fluid compartment 50, the membrane 18 has to be pressed against the inner surface of the housing 12 before each new air pulse. The force needed to press the membrane 18 against the housing 12 is created by the column of liquid that is created by the conduit 42 attached to the liquid outlet, whereby its weight will create the necessary force. It is to be understood that a longer conduit 42 will create a heavier liquid column that will more easily press the membrane 18 against the housing 12. However, if the weight is too large, that will affect the pumping capacity of the pump. Thus, if the weight increases, then the pressure of the air pulse also has to be increased. Further the liquid column also constitutes the transport of water out of the system.

[0038] The expansion vessel 46 will ensure that the effect of the air pulses are limited and that they are balanced against the pressure of the system as such, where the aim is to have the pump working with as small recoil forces as possible because each air pulse creates a downward movement inside the pump housing 12 when the membrane 18 is compressed and pushes the liquid upwards.

[0039] The check valve 30 at the inlet 14 has an important function because it prevents the liquid that is drawn into the pump 10 from flowing back between the air pulses. On the one hand, a normal check valve 30, possibly integrated with a mesh filter 32, may be used.

[0040] On the other hand, the simple and yet effective check valve describe above may be utilised for the function. Preferably the same type of tubular membrane is used in the check valve as in the pump. In this manner a very cost-effective solution is obtained. For instance, an ordinary bicycle hose, such as from a BMX-cycle, can be used both in the pump and in the check valve. The number and the size of the passages 38 in the body of the check-valve may be chosen depending on application.

[0041] It is to be understood that the embodiment described above and shown in the drawings is to be regarded only as a non-limiting example and that it may be modified in many ways within the scope of the patent claims.