Patent Grant
8967971
The present invention relates to a pump. In particular, the present invention relates to a fluid pump, especially a fluid pump that utilizes the principle of solid-body rotation.
Pumps are commonly used for a wide variety of different applications. Common conventional varieties of pump include positive displacement pumps (such as those comprising a reciprocating piston in a cylinder) and non-positive displacement pumps (such as those comprising centrifugal impellers which fling fluid into a diffusing passageway).
Conventional centrifugal fluid pumps employ a rotating impeller that draws in fluid (for instance, water or air) before ejecting the fluid at high speed from the tips of the impeller blades into one or more diffusing passageways. The purpose of the diffusing passageways is to reduce the high kinetic energy imparted to the fluid by the impeller. This is achieved through providing the diffusing passageways with a progressively increasing cross sectional area that causes the fluid to decelerate in a controlled manner. As fluid speed decreases, an increase in static pressure takes place.
This increase in static pressure is required in many pump applications in order to overcome downstream resistance to the flow of fluid caused by fluid drag against pump walls, surfaces, bends, cross-sectional area changes or introduced elements such as filters.
These conventional pumps suffer from a number of significant disadvantages. Firstly, the impeller flings fluid (such as water) off the tips of the blades into the diffusing passageways but not does force it into the diffusing passageways. This means that the diffuser inlets must be placed close to the blade tips so that the fluid velocity is as high as practical as the fluid enters the passageways. This arrangement results in wake collisions which generate a significant amount of noise.
Another disadvantage of conventional pumps is that, due to a large number of cross-sectional area changes through the passageways within the impeller, casing and pump body, the velocity of the fluid changes repeatedly as the fluid moves through the pump. These velocity changes generally result in a decrease in fluid momentum, meaning that additional power input is required to compensate for the loss in fluid momentum, resulting in a reduction in the efficiency of the pump.
A further disadvantage of conventional pumps is the significant cost of manufacturing the one or more diffusing passageways that are integral to conventional centrifugal pumps.
Thus, there would be an advantage if it were possible to provide a fluid pump that reduced or eliminated at least some of the inefficient design features of conventional centrifugal fluid pumps, thereby providing a pump having improved efficiency and reduced noise.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.
Throughout this specification, the term “comprising” and its grammatical equivalents shall be taken to have an inclusive meaning unless the context of use indicates otherwise.
It is an object of the present invention to provide a fluid pump which may overcome at least some of the abovementioned disadvantages, or provide a useful or commercial choice.
In a first aspect, the invention resides broadly in an apparatus for pumping or compressing a fluid, the apparatus comprising:
The housing of the apparatus may be a unitary housing, a two-part housing or a multiple part housing in which the parts are attached together. Typically, the housing comprises a two-part housing consisting of an upper part and a lower part which are fastened together typically via separate fasteners such as screws, bolts and the like. Each housing part may be of any suitable size, shape or configuration. In some embodiments of the invention, a first housing part may contain the at least one inlet while a second housing part may contain the at least one outlet. Alternatively, each housing part may contain both the at least one inlet and the at least one outlet.
The front and rear walls of the housing may be of any suitable size, shape or configuration. However, in a preferred embodiment of the invention, the front and rear walls of the housing are substantially the same size and shape as one another. In some embodiments of the invention, the front and rear walls of the housing are substantially circular in plan view. Thus, in this embodiment of the invention, the housing is substantially cylindrical.
The one or more inlets may be located at any suitable point on the housing. For instance, the one or more inlets may be located in the side wall or the front wall of the housing. The one or more inlets may be located such that fluid enters the apparatus tangentially to the side wall of the apparatus.
Alternatively, the one or more inlets may be located substantially centrally in the front wall of the apparatus. In this embodiment of the invention, the impeller may be located such that at least a portion of the impeller extends outwardly beyond at least a portion of the housing.
In another embodiment of the invention, the apparatus may comprise one or more tangential inlets and one or more substantially centrally located inlets.
As previously mentioned, the front wall of the housing includes one or more inlets located substantially centrally therein. In some embodiments of the invention, the one or more inlets may be associated with one or more inlet passageways, such that fluid entering the apparatus passes through the one or more inlet passageways prior to entering the apparatus through the one or more inlets.
The one or more inlet passageways may be of any suitable size, shape or configuration. In some embodiments of the invention, the one or more inlet passageways may be adapted to connect to the front wall of the housing. Alternatively, in some embodiments of the invention, the front wall of the housing may consist of a raised portion at or adjacent the one or more inlets that projects outwardly from the surface of the front wall. In these embodiments of the invention, the raised portion may be adapted for connection to the one or more inlet passageways.
In some embodiments, the one or more inlet passageways may be formed integrally with the housing. In other embodiments of the invention, the one or more inlet passageways may be formed separately from the housing and may be adapted for temporary or permanent engagement therewith, using any suitable technique.
The impeller may be of any suitable form. However, in a preferred embodiment of the present invention, the impeller is provided with one or more blades and, more preferably, a plurality of blades. In a most preferred embodiment of the invention, the impeller is provided with a plurality of curved blades.
As has been stated previously, the impeller may be located at least partially within the at least one inlet such that at least a portion of the impeller extends outwardly beyond at least a portion of the front wall. In embodiments of the invention in which the one or more inlets are provided with a raised portion, the impeller may be located at least partly within the raised portion. Alternatively, the impeller may be located at least partly within the inlet passageway, if one is present.
As previously mentioned, the walls of the housing serve to define a fluid rotation chamber. In some embodiments of the invention, fluid is introduced into the apparatus through the one or more inlets, is ejected from the impeller into the fluid rotation chamber. In a preferred embodiment of the invention, the rotation of fluid within the fluid rotation chamber is in the form of solid-body rotation, in which the rotating fluid acts substantially as a solid body rather than a fluid. Preferably, the impeller and the body of rotating fluid in the fluid rotation chamber are substantially co-axial with one another.
There are a number of benefits to achieving solid-body rotation of the fluid. Firstly, the rotating fluid effectively stores momentum, and considerable force is required to slow or arrest the rotation of the fluid. Secondly, as the fluid is rotating as a solid body, substantially no shear forces exist within the body of fluid, meaning that there is substantially no turbulence in the fluid. This lack of turbulence assists in maintaining the efficiency of the apparatus.
The one or more outlets may be of any suitable size, shape or configuration. In a preferred embodiment of the present invention, the one or more outlets may be located tangentially to the direction of rotation of fluid within the fluid rotation chamber. Preferably, the one or more outlets are located in the side walls of the housing. More preferably, the one or more outlets are located at a point in the side walls remote from the one or more inlets in order to reduce the degree of turbulence in the fluid. In a most preferred embodiment of the invention, the apparatus comprises one outlet.
As the fluid rotates in the fluid rotation chamber, the pressure of the fluid is at its greatest adjacent the inner surface of the housing. Thus, by locating the outlet tangentially in a side wall of the housing, the rotating fluid exiting the apparatus through the outlet has the highest pressure required to overcome downstream resistance.
The outlet may be in fluid communication with an outlet passageway (such as a pipe or conduit). While the passageway outlet may be of any suitable shape or configuration, in a preferred embodiment of the invention the outlet passageway is substantially square or rectangular in cross-section along at least a portion of its length. In some embodiments of the invention, the outlet passageway may be substantially square or rectangular in cross-section along the entirety of its length.
In a second aspect, the invention resides broadly in an apparatus for pumping or compressing a fluid, the apparatus comprising:
The rotation means may be of any suitable form provided that the rotation means imparts sufficient rotation to the fluid entering the apparatus. For instance, the rotation means may comprise one or more impellers, one or more magnetic (or magnetizable) rotating members within the housing actuable by exerting a magnetic or electromagnetic attraction or repulsion from outside the housing, one or more water jets directed tangentially within the housing, or the like, or any combination thereof.
In embodiments of the invention in which the rotation means comprises one or more impellers, the one or more impellers may be located at any suitable position within the apparatus. For instance, in embodiments of the invention in which a single impeller is present, the impeller may be positioned at least partially within an inlet of the apparatus or wholly within the fluid rotation chamber. The impeller may be positioned at any suitable location within the fluid rotation chamber, such as adjacent an inlet, at a point between the front and rear walls of the housing, or adjacent the rear wall of the housing and so on. In embodiments of the invention in which two or more impellers are present, the two or more impellers may be located at any suitable combination of positions.
The one or more inlets may be located at any suitable point on the housing. For instance, the one or more inlets may be located in the side wall or the front wall of the housing. The one or more inlets may be located such that fluid enters the apparatus tangentially to the side wall of the apparatus.
Alternatively, the one or more inlets may be located substantially centrally in the front wall of the apparatus.
In another embodiment of the invention, the apparatus may comprise one or more tangential inlets and one or more substantially centrally located inlets.
In a third aspect, the invention resides broadly in an apparatus for pumping or compressing a fluid, the apparatus comprising:
The one or more inlets may be located at any suitable point on the housing. For instance, the one or more inlets may be located in the side wall or the front wall of the housing. The one or more inlets may be located such that fluid enters the apparatus tangentially to the side wall of the apparatus.
Alternatively, the one or more inlets may be located substantially centrally in the front wall of the apparatus. In this embodiment of the invention, the impeller may be located such that at least a portion of the impeller extends outwardly beyond at least a portion of the housing.
In another embodiment of the invention, the apparatus may comprise one or more tangential inlets and one or more substantially centrally located inlets.
As mentioned above, the angle at which the front and rear walls join the one or more side walls is a tightly-radiused curve. In a preferred embodiment of the invention, the radius of the tightly-radiused curve is less than 10 mm. More preferably, the radius of the tightly-radiused curve is less than 5 mm. Still more preferably, the radius of the tightly-radiused curve is between 1 mm and 2 mm. The radius of the tightly-radiused curve between the front wall and the side wall may be the same or different to that between the rear wall and the side wall. In a preferred embodiment of the invention, however, the radius of the tightly-radiused curve between the front wall and the side wall may be substantially identical to that between the rear wall and the side wall.
By providing these tightly-radiused curves at the points at which the front and rear walls join the side walls, a fluid rotation chamber having an almost square or rectangular cross-sectional shape may be achieved. It has surprisingly been found that providing a fluid rotation chamber having this substantially cylindrical geometry results in improvements to the efficiency of the apparatus.
In a fourth aspect of the invention, the invention resides broadly in an apparatus for pumping or compressing a fluid, the apparatus comprising:
The one or more inlets may be located at any suitable point on the housing. For instance, the one or more inlets may be located in the side wall or the front wall of the housing. The one or more inlets may be located such that fluid enters the apparatus tangentially to the side wall of the apparatus.
Alternatively, the one or more inlets may be located substantially centrally in the front wall of the apparatus. In this embodiment of the invention, the impeller may be located such that at least a portion of the impeller extends outwardly beyond at least a portion of the housing
In another embodiment of the invention, the apparatus may comprise one or more tangential inlets and one or more substantially centrally located inlets.
In this embodiment of the invention, it is preferred that the cross-sectional shape of the fluid rotation chamber is substantially square or rectangular. It has surprisingly been found that providing a fluid rotation chamber having this geometry results in improvements to the efficiency of the apparatus.
In some embodiments of the invention (and equally applicable to all aspects of the present invention), the apparatus may be provided with one or more outlet tubes. The one or more outlet tubes may be of any suitable size, shape or configuration. In a preferred embodiment of the invention, a first end of the one or more outlet tubes may extend at least partially into the fluid rotation chamber. The second end of the one or more outlet tubes may extend to the one or more outlets. Alternatively, the second end of the one or more outlet tubes may extend beyond the one or more outlets, such as, for instance, at least partially into the one or more outlet pipes.
The cross-sectional area of the one or more outlet tubes may be of any suitable type. In some embodiments of the invention, the cross-sectional area of the one or more outlet tubes varies across the length of the outlet tubes, while in other embodiments of the invention, the cross-sectional area of the one or more outlet tubes is substantially constant over the length of the one or more outlet tubes. In embodiments of the invention in which a plurality of outlet tubes are present, all of the plurality of outlet tubes may have cross-sectional areas that are substantially constant over the length of the outlet tubes, or all of the outlet tubes may have cross-sectional areas that vary across the length of the outlet tubes, or the outlet tubes may be a combination of the two.
Preferably, the one or more outlet tubes are sized so that the amount of fluid leaving the fluid rotation chamber through the one or more outlet tubes is not so great that the remaining fluid in the fluid rotation chamber can no longer rotate under the principle of solid-body rotation. In some embodiments of the present invention, the one or more outlet tubes have a foil-like cross-sectional shape.
In embodiments of the invention in which a plurality of outlets are present, each outlet may be provided with one or more outlet tubes.
In some embodiments of the invention, the one or more outlet tubes may be the one or more outlets.
By locating the first end of the one or more outlet tubes within the fluid rotation chamber, it can be ensured that fluid rotating at a higher velocity within the chamber than the fluid rotating close to the wall of the housing will be discharged through the one or more outlets. In some embodiments of the invention, the fluid that flows through the one or more outlets is a combination of the higher velocity fluid that discharges through the outlet through the one or more outlet tubes, and the lower velocity fluid rotating close to the wall of the housing. In this embodiment of the invention, the average velocity of the fluid exiting the apparatus through the one or more outlets may be increased through the addition of higher velocity fluid exiting the outlet through the one or more outlet tubes.
In some embodiments of the invention (and equally applicable to all aspects of the present invention), the impeller may have a discharge portion from which the fluid is discharged into the fluid rotation chamber. While the discharge portion of the impeller may be located at any suitable point, in a preferred embodiment of the invention, the discharge portion of the impeller may be located within the fluid rotation chamber. The discharge portion of the impeller may be located at any suitable point within the fluid rotation chamber, such that fluid may be discharged into substantially any point of the fluid rotation chamber.
In some embodiments of the invention the fluid vortex in the fluid rotation chamber may be so strong that centripetal forces result in the pressure in the fluid concentrating at the periphery of the fluid rotation chamber. This, in turn, means that the fluid pressure adjacent to the core of the fluid vortex becomes so low that the fluid may cavitate. Thus, in some embodiments (and equally applicable to all aspects of the present invention), the apparatus may be provided with anti-cavitation means adapted to prevent fluid cavitation.
The anti-cavitation means may be of any suitable size, shape or configuration. In a preferred embodiment, however, the anti-cavitation means are positioned at least partly in the fluid rotation chamber and are adapted to rotate therein. The rotation of the anti-cavitation means may be due to the action of the impeller inducing the rotation of the anti-cavitation means, or, alternatively, the anti-cavitation means may be associated with the impeller in such a way that any rotation of the impeller results in the rotation of the anti-cavitation means. In some embodiments, the anti-cavitation means may be attached to the impeller using any suitable technique.
Preferably, the anti-cavitation means extends between the front and rear walls of the fluid rotation chamber. The anti-cavitation means may extend part-way between the front and rear walls of the fluid rotation chamber, or may extend substantially the entire distance between the front and rear walls of the fluid rotation chamber.
The anti-cavitation means may have any suitable diameter. For instance, the diameter of the anti-cavitation means may be larger than or smaller than the diameter of the impeller with which it is associated. In one embodiment, the diameter of the anti-cavitation means is approximately the same as the diameter of the impeller.
In a preferred embodiment, the anti-cavitations means may be a substantially cylindrical element extending at least part-way between the front and rear walls of the fluid rotation chamber. More preferably, the antic-cavitation means may be a hollow cylinder, for instance a spigot or drum, although it will be understood that the anti-cavitation means may alternatively be provided with a plurality of passages therethrough. Further, the cylindrical wall of the anti-cavitation means may be provided with one or more openings such that fluid may pass between the interior of the anti-cavitations means and the fluid rotation chamber at an angle that is approximately perpendicular to the axis about which the anti-cavitation means rotates.
It is envisaged that the anti-cavitation means may be positioned within the fluid rotation chamber so as to substantially replace a cavitating core of the fluid vortex.
The anti-cavitation means may be fabricated from any suitable material (such as, but not limited to, metal, plastic, fibreglass, glass, wood etc, or a combination thereof). However, as the fluid within the fluid rotation chamber behaves essentially as a solid body, it is envisaged that the presence of the anti-cavitation means within the fluid rotation chamber will not have a detrimental effect on the rotation of the fluid.
It is envisaged that the rotation of the anti-cavitation means may also result in the entrainment of fluid in addition to the fluid entrainment achieved by the rotation of the impeller. Thus, the total energy introduced into the fluid is greater than that of the fluid injection achieved by the impeller alone. It is for this reason that the total energy injection may, in some embodiments, cause the fluid vortex to rotate at a different rate (either faster or slower) than the RPM of the impeller. Also, in some embodiments, the RPM of the fluid vortex may be less or the same RPM as the impeller but the speed of the fluid in the vortex close to the vortex periphery may be higher than the speed of the impeller periphery or spigot or drum surface because that part of the fluid vortex is a larger diameter than either the impeller or spigot.
In some embodiments of the invention, a motor may be located within the hollow cylinder of the anti-cavitation means. In some instances, the anti-cavitation means may comprise the motor casing. In this embodiment of the invention the motor may be positioned on the rear wall of the fluid rotation chamber.
The advantages of this arrangement are that it is space saving, with reduced manufacturing costs. In addition, the motor may be water cooled in this method rather than the more conventional air cooling of motors.
A skilled addressee will understand that, in many conventional centrifugal pumps, a seal is required to prevent fluid having a high static pressure from leaking out of the inlet of the pump. Typically, these seals are labyrinth seals and possess a number of labyrinthine turns that the fluid must follow. Due to the geometry of these seals, they are typically fabricated with high precision, making them relatively costly to produce.
In some embodiments of the invention (and equally applicable to all aspects of the present invention) labyrinth seals of the type described above may not be required in the present apparatus. The reason for this is that, as the fluid in the fluid rotation chamber rotates at relatively high rpm, the static pressure in the fluid vortex concentrates at or adjacent the periphery of the vortex. Fluid closer to the centre of the fluid rotation chamber (approximately where a labyrinth seal would be located in conventional pumps) is typically of a relatively low pressure, and often at a lower pressure than then fluid entering the apparatus through the inlet. Thus, a labyrinth seal may not be required.
It is envisaged that the amount of fluid leakage from the inlet area past the front of the anti-cavitation means (if present) will be negligible or inconsequential.
In some embodiments, the housing may include one or more recesses, notches, grooves or the like in which at least a portion of the anti-cavitation means is received during use, thereby further reducing the requirement for precise manufacturing tolerances.
A skilled addressee will understand that, in many conventional centrifugal pumps, a seal is required to prevent fluid leaking along the shaft of the motor associated with the impeller and into the motor. Often, this seal is a mechanical seal, such as a seal composed of one smooth surface of carbon fibre or ceramic rotating against a stationary surface of carbon fibre or ceramic. The internal pressure of a conventional centrifugal pump is greater than atmospheric pressure. As a result, any fluid being pumped is prone to leakage through openings such as where the motor shaft enters the pump body.
As has been previously stated, the pressure in the fluid rotation chamber in the region normally occupied by the mechanical seal is generally lower than the pressure external to the apparatus. As a result, the need for a mechanical seal is reduced or even eliminated altogether. In some embodiments, simple seals (such as O-rings may be sufficient, or, alternatively, a soft material (such as rubber) may be used to prevent fluid leakage along the motor shaft. In some applications, however, a mechanical seal may be desired or required.
In embodiments of the invention in which a soft material is used as a seal, it has been observed that seal movement in the axial direction of the shaft may occur depending on the operating condition of the apparatus.
Thus, in some embodiments, it is preferred that the seal may be provided with means for preventing movement of the seal in the axial direction of the motor shaft. Any suitable means may be provided, although in a preferred embodiment of the invention, the means may include providing one or more angled surface on the outer surface and/or inner surface of the seal.
The purpose of the one or more angled surfaces is that, as the motor shaft rotates, the angled surfaces generate forces that hold the seal against the shaft, therefore preventing movement of the seal in the axial direction of the motor shaft. With this purpose in mind, it will be understood that the one or more angled surfaces may be provided with any suitable geometry to achieve this purpose.
It is envisaged that one or more angled surfaces on the inner surface of the seal may be provided so as to ensure that the seal is in continuous contact with the surface of the motor shaft, even when the diameter of the motor shaft varies along its length.
In a preferred embodiment of the invention, the seal may comprise a substantially annular seal having an passageway therein through which the motor shaft may pass.
In an alternative embodiment, the seal may comprise a sealed bearing.
The present invention provides a number of advantages over the prior art. Firstly, the simplicity of the design of the present invention ensures low manufacturing costs. In addition, the present invention has significantly lower operational costs associated with it.
Further, by eliminating the need to provide one or more diffusing passageways, the present invention produces significantly less noise than prior art devices. This was not previously thought possible, as conventional understanding is that, without diffusing passageways, the pressure development in a pump is inadequate and the pump would operate at sub-optimal efficiency.
An embodiment of the invention will be described with reference to the following drawings in which:
It will be appreciated that the drawings have been provided for the purposes of illustrating preferred embodiments of the present invention and that the invention should not be considered to be limited solely to the features as shown in the drawings.
In
The apparatus 10 further comprises an outlet pipe 15 located tangentially to the circular front wall 11, the outlet pipe 15 being rectangular along a portion of its length.
It may be seen in this Figure that a fluid rotation chamber 18 is defined inside the apparatus 10 by the rear wall 16, the side walls 19 and the front wall (not shown). When in use, fluid rotates inside the fluid rotation chamber 18 according to the principles of solid-body rotation, such that the fluid with the greatest momentum (i.e. that rotating within the chamber 18 adjacent the side wall 19 is ejected from the apparatus 10 through the outlet 20. Fluid exiting the apparatus 10 through the outlet 20 then travels through the outlet pipe 15.
In
In this Figure, an inlet passageway 22 is also shown. The inlet passageway 22 is in fluid communication with the inlet (obscured). In this embodiment of the invention, the inlet passageway 22 is formed integrally with the front wall 11 of the apparatus 10.
In
The corner 23 at which the front wall 11 joins the side wall 19 and the corner 24 at which the rear wall 16 joins the side wall 19 are provided with tightly-radiused curves. In the embodiment of the invention illustrated in
The radius of the tightly-radiused curves is maintained as low as possible in order to provide the fluid rotation chamber 18 with a suitable geometry for encouraging solid-body rotation of the fluid therein. It has surprisingly been found that providing the fluid rotation chamber 18 with such tightly-radiused curves at the corners where the front 11 and rear 16 walls join the side walls 19 increases the efficiency with which the apparatus 10 operates by promoting solid-body rotation of the fluid.
In some embodiments of the invention, the corners 23, 24 may be at substantially 90° angles. While this would provide a geometry that would improve the efficiency of the pump, it is also possible that this would lead to the accumulation of mechanical stresses at the corners 23, 24. Thus, providing a tightly-radiused curve at the corners 23, 24 may overcome the accumulation of mechanical stresses without any significant loss of pump efficiency.
It may be further seen in
In
It may also be seen more clearly in this Figure that the front wall 11, side wall 19 and rear wall (obscured) serve to define an essentially cylindrical housing for the apparatus 10.
In
In the embodiment of the invention shown in
In
In
In
It may further be seen that the spigot 40 extends substantially the entire distance between the front wall 11 and the rear wall 16 of the fluid rotation chamber 18.
In
In this embodiment, a labyrinth seal 41 is located within the inlet 12 of the apparatus 10.
The anti-cavitation means 40 of
In
It may be seen in this Figure that the anti-cavitation means 40 is associated with the impeller 13 and extends both from the impeller 13 in the direction of the front wall 11, and from the impeller in the direction of the rear wall 16.
Similarly, in
In
In
A similar arrangement is illustrated in
Turning finally to
Those skilled in the art will appreciate that the present invention may be susceptible to variations and modifications other than those specifically described. It will be understood that the present invention encompasses all such variations and modifications that fall within its spirit and scope.
The present application is a continuation-in-part patent application of international patent application no. PCT/AU2009/000421, and further claiming priority from Australian provisional patent application nos. 2010900215 filed 21 Jan. 2010 and 2010901877 filed 3 May 2010.
| Number | Name | Date | Kind |
|---|---|---|---|
| 2160666 | McMahan | May 1939 | A |
| 2272454 | Wilfley | Feb 1942 | A |
| 2329696 | Thomas | Sep 1943 | A |
| 2635548 | Brawley | Apr 1953 | A |
| 3628881 | Herrmann | Dec 1971 | A |
| 4082478 | Schmitz | Apr 1978 | A |
| 4375937 | Cooper | Mar 1983 | A |
| 4926629 | Eick et al. | May 1990 | A |
| 6015434 | Yamane | Jan 2000 | A |
| 20050265832 | Horng et al. | Dec 2005 | A1 |
| 20110008153 | Kato et al. | Jan 2011 | A1 |
| Number | Date | Country |
|---|---|---|
| 1959118 | May 2007 | CN |
| 2003-0047711 | Jun 2003 | KR |
| WO 2010147932 | Dec 2010 | WO |
| Entry |
|---|
| International Search Report as issued in the parent International Application PCT/AU2009/000421; mailed Jul. 27, 2009. |
| Written Opinion of the International Searching Authority as issued in the parent International Application PCT/AU2009/000421; mailed Jul. 27, 2009. |
| English Translation of the Abstract of KR 2003-0047711; Kang Chi Hwang, “Liquid Feeding Pump Having Conical Shaped Impeller”, published Jun. 18, 2003. |
| Number | Date | Country | |
|---|---|---|---|
| 20110064568 A1 | Mar 2011 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/AU2009/000421 | Apr 2009 | US |
| Child | 12901671 | US |
