CROSS REFERENCE TO RELATED APPLICATIONS

[0001 ] The entire disclosure of Australian Provisional Patent Application 202290269 is incorporated herein by reference.

TECHNICAL FIELD

[0002] The present invention relates to pump and filter systems.

[0003] The invention has been devised particularly, although not necessarily solely, in relation to submerged inline pumps and their filter systems.

BACKGROUND ART

[0004] The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.

[0005] Pump systems adapted to be immersed and operate within bodies of fluid require perfect sealing system to avoid the fluid entering the interior of the pump system.

[0006] Current pump systems, such as the ones used in swimming pools and ponds have a mechanical seal to keep fluid from leaving the wet end of the pump which can then ingress into the bearings and the motor in the case of an electric pump.

[0007] All mechanical seals fail eventually due to normal wear and tear and commonly the weakening of the spring mechanism part of the mechanical seals.

[0008] Further, in view that the body of pump systems to be immersed in body of fluids are perfectly sealed, heat (generated by the electric motor driving the fluid flow) stays trapped within the pump body damaging as time goes by the components that make up the pump system, for example, the bearings, seals and electric motor.

[0009] Furthermore, rotation of the rotor of the electric motor driving the fluid flow, is supported by bearings (such as flat rings acting as bearings or ball bearings) which require constant lubrication and cooling. Provision of lubrication and cooling systems in pumps to be fully immersed in fluid during operation thereof has been challenging.

[0010] It is against this background that the present invention has been developed.

SUMMARY OF INVENTION

[0011 ] According to a first aspect of the invention there is provided a pump assembly comprising a shell, an inner casing adapted to allow fluid therethrough comprising an inner space defining a first fluid pathway, and an electric motor located within the inner space and adapted for fluid to traverse the electric motor for propulsion of the fluid, the electric motor comprises a stator and a rotor defined by a hollow body operatively connected to the stator for rotation of the rotor during operation of the stator, the rotor comprising a blade assembly within the hollow body for rotation with the rotor for propulsion of the fluid traversing the pump assembly, wherein the shell and/or inner casing are configured so that a second fluid pathway is defined around the inner casing for cooling of the inner casing and the interior of the inner casing.

[0012] Preferably, the stator comprises a heat sink surrounding the stator.

[0013] Preferably, the heat sink comprises fins extending into the second fluid pathway.

[0014] Preferably, the heat sink is configured as cooling fins arranged in a spaced apart relationship with respect to each other surrounding the stator.

[0015] According to a second aspect of the invention there is provided a pump assembly comprising a shell, an inner casing adapted to allow fluid therethrough comprising an inner space defining a first fluid pathway, and an electric motor located within the inner space and adapted for fluid to traverse the electric motor for propulsion of the fluid, the electric motor comprises a stator and a rotor defined by a hollow body operatively connected to the stator for rotation of the rotor during operation of the stator, the rotor comprising a blade assembly within the hollow body for rotation with the rotor for propulsion of the fluid traversing the pump assembly, wherein the shell and/or inner casing are configured so that a second fluid pathway is defined around the inner casing, wherein the inner casing is configured for diverting a portion of fluid in the second fluid pathway into the interior of the inner casing for fluid contacting bearings of ends of the rotor for interaction thereof.

[0016] Preferably, the interaction comprises lubrication and/or cooling of the bearings.

[0017] Preferably, the inner casing comprises a discharging section having a first entry point and a first exit point, and a suction section having a second entry point and a second exit point, the first entry point and the second exit point being adapted to be joined together for defining the inner casing.

[0018] Preferably, each of the sections comprises a passage traversing longitudinally each section for defining the first fluid pathway.

[0019] Preferably, the discharging section comprises an indentation indenting into the first entry point, and the suction section comprises an indentation indenting into the second exit point for defining the inner space adapted to receive at least partially the electric motor when the discharging and the suction sections are joined together.

[0020] Preferably, the shell comprises a first jacket for receiving the discharging section, and a second jacket for receiving the suction section, the first and second jackets being adapted to be joined together to define the shell.

[0021 ] Preferably, an outer surface of each of the discharging and suction section comprises ribs arranged in a spaced apart relationship with respect to each other around the outer surface.

[0022] Preferably, neighbouring ribs define a plurality of the second fluid pathways having as side walls the neighbouring ribs and as roofs the sections of the inner surface of the jackets located between the neighbouring ribs.

[0023] Preferably, the outer surface of the discharging section comprises a plurality of grooves, each groove extends longitudinally starting at a location adjacent of the first exit point of the discharging section to the first entry point of the discharging section.

[0024] Preferably, there is provided an opening at the location adjacent the first exit point, the opening traversing the discharging section to permit fluid flow therethrough.

[0025] Preferably, each groove has an open end at the outer periphery of the first entry point of the discharging section.

[0026] Preferably, each groove comprises a tubing having a first end inserted in the opening for receiving fluid flowing through the pump body, and the tubing extending beyond the outer periphery of the first entry point for defining a fluid path from the interior of the discharging section for delivering fluid to the suction section via the tubing.

[0027] Preferably, the suction section comprises inlets arranged in a spaced apart relationship with respect to each other around the outer periphery of the second exit point of the discharge section, the inlets being adapted to receive end sections of the tubing extending beyond the outer periphery of the first entry point of the discharging section.

[0028] Preferably, the indentation of the suction section comprises a rim comprising a plurality of openings arranged in a spaced apart relationship with respect to each other around the rim, each inlet being fluidly connected to a first opening through a passage.

[0029] Preferably, the fluid exiting the first openings is delivered to bearings for interaction with the bearings.

[0030] According to a third aspect of the invention there is provided a pump assembly comprising a shell, an inner casing adapted to allow fluid therethrough comprising an inner space defining a first fluid pathway, and an electric motor located within the inner space and adapted for fluid to traverse the electric motor for propulsion of the fluid, the electric motor comprises a stator and a rotor defined by a hollow body operatively connected to the stator for rotation of the rotor during operation of the stator, the rotor comprising a blade assembly within the hollow body for rotation with the rotor for propulsion of the fluid traversing the pump assembly from one end to another end of the first fluid pathway, wherein the blade assembly is attached to an end of the inner casing.

[0031] In an arrangement, the blade assembly is releasably attached to the one end of the body.

[0032] Preferably, the other end and comprises a flow straightener.

[0033] According to a fourth aspect of the invention there is provided a pump assembly comprising a shell, an inner casing adapted to allow fluid therethrough comprising an inner space defining a first fluid pathway, and an electric motor located within the inner space and adapted for fluid to traverse the electric motor for propulsion of the fluid, the electric motor comprises a stator and a rotor defined by a hollow body operatively connected to the stator for rotation of the rotor during operation of the stator, the rotor comprising a blade assembly within the hollow body for rotation with the rotor for propulsion of the fluid traversing the pump assembly, the rotor comprises a hollow body having an outer surface facing an inner surface of the stator, the outer surface comprising at least one pocket adapted to receive at least one magnet.

[0034] Preferably, the pocket comprises an open end, and is configured for slideably receiving the magnet.

[0035] In a particular arrangement, the outer surface comprises a plurality of pockets arranged in a spaced apart relationship with respect to each other, each pocket comprising a curved magnet.

[0036] In a particular arrangement, there at least four pockets for receiving the magnets.

[0037] Preferably, there are at least four curved magnets.

[0038] In an alternative arrangement, the pump assembly comprises the discharging section incorporating the electric motor, and a centrifugal outlet for receiving the fluid exiting the discharging section and discharging the fluid.

[0039] Preferably, the hollow body comprises open ends defining outer peripheries for receiving bearings such as ceramic or ceram ic/carbon fibre bearings.

[0040] In an arrangement, there may be provided a flow sensor in the jacket to detect any interruption of fluid flow within the pump assembly. This is particularly advantageous in the particular arrangement where the bearing comprises carbon/ceramic bearing which need to operate only during the presence of fluid flow.

[0041] Preferably, the outer peripheries comprises openings arranged in a spaced apart relationship with respect to each other for receiving ballast for balancing of the body of the rotor.

[0042] According to a fifth aspect of the invention there is provided a pump assembly comprising a shell, an inner casing adapted to allow fluid therethrough comprising an inner space defining a first fluid pathway, and an electric motor located within the inner space and adapted for fluid to traverse the electric motor for propulsion of the fluid, the electric motor comprises a stator and a rotor defined by a hollow body operatively connected to the stator for rotation of the rotor during operation of the stator, the rotor comprising a blade assembly within the hollow body for rotation with the rotor for propulsion of the fluid traversing the pump assembly from one end to another end of the first fluid pathway, wherein the hollow body comprises open ends permitting traversing of the fluid through the rotor, wherein each end has a bearing supporting rotation of the rotor within the inner casing.

[0043] Preferably, the inner casing comprises indentations opposite with respect to each other for receiving ends of the rotor for supporting rotation of the rotor within the inner space.

[0044] Preferably, each indentation comprises a sealing assembly to impede fluid leakage from the inner space to the exterior of the inner space.

[0045] Preferably, the inner casing comprises a discharging section having a first entry point and a first exit point, and a suction section having a second entry point and a second exit point, the first entry point and the second exit point being adapted to be joined together for defining the inner casing.

[0046] Preferably, the discharging section and the suction section comprises the indentations arranged opposite with respect to each other for receiving ends of a protective cylinder surrounding the rotor.

[0047] In an arrangement, the sealing assembly comprises a flat gasket resting within a groove of the indentation of each section, a pair of spaced apart O-ring gaskets surrounding the ends of the protective cylinder received within the indentations.

[0048] Preferably, each bearing abut the end walls of the respective indentation where each end of the rotor is inserted.

[0049] According to a sixth aspect of the invention there is provided a filter unit comprising a body having a receiving section having an inlet and a first open end, and a discharging section having an outlet and a second open end to allow fluid flow through the body, the first and second open ends are adapted to be joined together, wherein the filter unit further comprises a filter medium sandwiched between the first and second open ends for extracting extraneous matter from the fluid.

[0050] Preferably, the receiving section comprises a chamber for containment of the extraneous matter.

[0051] According to a seventh aspect of the invention there is provided a pump system comprising the pump assembly in accordance with any one of the first to fourth aspect of the invention and the filter unit in accordance with the fifth aspect of the invention fluidly connected with respect to each other.

[0052] According to an eighth aspect of the invention there is provided a method for balancing a body adapted to be rotated around its longitudinal axis, the body comprising a first end and a second end arranged in a spaced apart relationship opposite with respect to each other along the longitudinal axis, wherein at least one of the first and second ends comprises openings intending longitudinally into the pump body, the method comprises the steps of:

(a) introducing ballast into the openings, and

(b) rotating the body about the longitudinal axis to confirm proper balancing of the body, and repeating the steps (a) and (b) until proper balancing has been accomplished.

[0053] According to a ninth aspect of the invention there is provided a rotor for operatively being connected to a stator of an electric motor, the rotor comprising a body adapted to allow fluid flow through the body from one end to the other end of the body, and a blade assembly fixed to the rotor for propelling the fluid flow traversing the body of the rotor during rotation of the rotor, wherein the blade assembly is attached to one of the ends of the body of the rotor.

[0054] Preferably, the other end comprises a flow straightener.

[0055] According to a tenth aspect of the invention there is provided an electric motor comprising a stator having a heat sink surrounding at least partially the stator, and a rotor for rotating within the stator, wherein the rotor comprises a rotor in accordance with the ninth aspect of the invention.

[0056] According to a eleventh aspect of the invention there is provided a centrifugal pump assembly comprising a shell comprising an inner space adapted to allow fluid flow from one end to the other end, an impeller fluidly connected to the other end, and an electric motor located within the inner space and adapted for fluid to traverse the electric motor for propulsion of the fluid, the electric motor comprises a stator and a rotor operatively connected to the impeller and the stator for rotation of the rotor during operation of the stator, the rotor comprising a blade assembly for rotation with the rotor for propulsion of the fluid traversing the pump assembly and being attached to the impeller, wherein the shell is configured so that a fluid pathway is defined around the stator for cooling of the electric motor.

[0057] Preferably, the centrifugal pump assembly comprises a centrifugal outlet attached to the other end of the shell for allowing fluid to exit the centrifugal pump assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Further features of the present invention are more fully described in the following description of several non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. The description will be made with reference to the accompanying drawings in which:

Figure 1 is a side perspective view of a particular arrangement of a pump assembly in accordance with a first embodiment of the invention; Figure 2 is a side perspective view of a particular arrangement of a filter unit accordance with the first embodiment of the invention;

Figure 3 is a side perspective view of a pump system, in disassembled condition, comprising the pump assembly shown in figure 1 and the filter unit shown in figure 2;

Figure 4 is a cross-sectional view of the pump system shown in figure 1 ;

Figure 5 is an exploded view of the pump system shown in figure 1 ;

Figure 6a is a perspective view of a particular arrangement of a pump (in opened condition) of the pump system shown in figure 1 ;

Figure 6b is a front perspective view of the suction section of the pump shown in figure 6a;

Figure 7 is a schematic perspective view of a particular arrangement of a rotor contained in the pump shown in figure 6a;

Figure 8 is a top perspective view of a particular arrangement of a centrifugal pump system in accordance with a second embodiment of the invention;

Figure 9 is a perspective view of a particular arrangement of a rotor comprising an impeller contained in the centrifugal pump shown in figure 8;

Figure 10 is a top perspective view of the discharging section with the cover removed of the centrifugal pump shown in figure 8;

Figure 11 is a front perspective view of the suction section of the pump shown in figure 8 comprising an electric motor;

Figures 12 and 13 are perspective views of the filter unit shown in figure 2, respectively in the assembled and disassembled condition;

Figure 14 is a perspective view of one end of a particular arrangement of a rotor for use in conjunction with the first and second embodiments of the invention; Figure 15 is a perspective view of the opposite end of the rotor shown in figure 14;

Figure 16 is a close-up side perspective view of the opposite end of the rotor as shown in figure 14;

Figure 17 is a perspective view of a particular arrangement of the blade assembly of the rotor shown in figure 14;

Figure 18 is a top perspective view of a particular arrangement of a cover for the opposite end of the rotor shown in figure 16;

Figure 19 is a perspective view of particular arrangement of the rotor shown in figure 15; and

Figures 20 to 22 show a particular arrangement of the sealing assembly of the pump system.

[0059] The figures depict embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognise from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.

DESCRIPTION OF EMBODIMENT(S)

[0060] Figures 1 and 2 depict, respectively, particular arrangements of a pump assembly 10 and a filtering unit 12 in accordance with the first embodiment of the invention. Figure 3 depict a pump system 14, in a disassembled condition, comprising the pump assembly 10 and the filtering unit 12.

[0061] The pump assembly 10 is adapted to be submerged in a fluid to propulse the fluid in which the pump assembly 10 is contained for moving the fluid from one location to another location. Propulsion of the fluid occurs due the pump assembly 10, as shown in figure 4, comprising a rotor assembly 16 (being defined by a hollow body) contained in a pathway 18 traversing the pump assembly 10 from a discharging end 20 for receiving the fluid, to a suction end 22. The rotor assembly 16 comprises an electric motor 24 having a stator 25 within which is located a rotor 26 having a blade assembly 28 which during rotation of the rotor 26 (due to the electromagnetic field generated by the coiling of the stator 25 and thus operatively connecting the rotor and stator) propels the fluid contained within the pathway 18 of the pump assembly 10.

[0062] Referring further to figure 4, the pump assembly 10 comprises a shell 30 defining an inner space 32 for containment of the electric motor 24.

[0063] Figure 5 shows an exploded view of the pump assembly 10. As shown in figure 5, the pump assembly 10 comprises two jackets 34 and 36 having each an inner space 38 and 40, which when the jackets 34 and 36 are joined together, define the inner space 32 of the shell 30.

[0064] Each jacket 34 and 36 comprises a rim 42 and 44 being adapted to abut each other when the jackets 34 and 36 are joined together to define the shell 30. The rims 42 and 44 comprises a plurality of openings 46 arranged in a spaced apart relationship with respect to each other for receiving screws 48 for fastening the jackets 34 and 36 together thus sealing the inner space 32 from the exterior.

[0065] Further, as mentioned before, the pump assembly 10 comprises an electric motor 24 within the shell 30. As show in figure 5, the electric motor 24 comprises: (1 ) the rotor 26 surrounded by a protective cylinder 50 acting as a spacer (for example, made out of carbon fibre), and (2) the stator 25 for receiving the rotor 26 with the protective cylinder 50.

[0066] In particular arrangement, there may be provided washers inside the indentations 60 surrounding the bearings 88 for the spacer to seal 50 against.

[0067] The stator 25 comprises a heat sink 27 for heat transfer to occur for cooling of the electric motor. In the particular arrangement shown in figure 5, the heat sink 27 is configured as cooling fins 29 (shown in figure 4) arranged longitudinally in a spaced apart relationship with respect to each other surrounding the stator 25.

[0068] The pump assembly 10 further comprises a pump body 52 containing the electric motor 24 shown in figure 4 and in disassembled condition in figures 5 and 6a. The pump body 52 comprises a shell 30 and an inner casing 53 contained within the shell 30. The shell 30 and/or an inner casing 53 are configured so that passageways 70 (defining a second fluid pathway) are defined between the inner surface of the shell 30 and the outer surface of the inner casing 53 permitting fluid to flow around the inner casing 53 as well through the casing 53, including the electric motor 24.

[0069] The fact that the fluid may flow around the inner casing 53 is particularly advantageous because it allows for cooling of the inner casing including its interior such as the electric motor 24. Another advantage is that fluid may be diverted to bearings 88.

[0070] In the particular arrangement shown in the figures, the inner casing 53 comprises two sections, in particular a discharging section 54 and a suction section 56 adapted to be joined together in a sealingly manner per a seal assembly 132. Figures 20 to 22 shows a particular arrangement of the sealing assembly 132. The sealing assembly 132 comprises a plurality of gaskets, in particular: a flat gasket 134 resting within a groove of the indentation 60 of each section 54 and 56, a pair of spaced apart O-ring gaskets surrounding the ends of the protective cylinder 50 received within the indentation 60.

[0071] Referring to figures 4 and 5, each of sections 54 and 56 comprises a passage 58 traversing longitudinally the sections 54 and 56, and indentations 60 defining the inner space 32 adapted to receive the electric motor 24. In particular, when the pump body 52 is assembled, by joining together the sections 54 and 56, the electric motor 24 is sandwiched between sections 54 and 56 and contained at least partially within the inner space 32.

[0072] As shown in figure 4, the indentation 60 are configured in such a manner that the electric motor 24 is sandwiched between the sections 54 and 56 of the pump body 52 in such a manner that the heat sink 27, in particular the cooling fins 29 extend out of the body pump 52 in order to enter in contact with the fluid flowing between the outer surface of the sections 54 and 56 and the inner surface of the jackets 34 and 36 ( the first fluid pathway) for heat transfer to occur to avoid overheating of the electric motor 24.

[0073] Further, the pathway 18 (the first fluid pathway) to allow fluid flow through the pump assembly 10 is defined by passages 58 when joining together the sections 54 and 56. The passages 58 extend from the entry points 66 to the exist points 64 of the sections 54 and 56. [0074] Referring now to figure 6a, the outer surface of each section 54 and 56 comprises ribs 68 arranged in a spaced apart relationship with respect to each other around the outer surface.

[0075] When the pump assembly is assembled, the ribs 68 abut the inner surfaces of the jackets 34 and 36 ensuring that sections 54 and 46 are concentrically arranged within the jackets 34 and 36. In this manner, passages 70 are defined having as side walls the neighbouring ribs 68 and as roofs, the sections of the inner surface of the sections 54 and 56 located between the neighbouring ribs 68. The passages 70 provide a pathway (defining the second fluid pathway) for allowing fluid to pass over the inner casing 53 for cooling of the inner casing 50 as well as the electric motor 24 due to the colling fins 29 as shown in figure 4 extending into the passage 70.

[0076] Furthermore, the outer surface of the discharging section 54 comprises a plurality of grooves 72 indenting into the outer surface of section 54. The grooves 72 extend longitudinally starting at a location adjacent of the exit point 64 of the section 54 to the entry point 66 of the section 54. As shown in 6a, each groove 72 has (1) an opening 73 (at the location adjacent the exit point 64) traversing the section 54 and (2) an open end 75 at the outer periphery of the entry point 66 of the discharging section 54.

[0077] The fact that the grooves 72 have openings 73 and open ends 75 permits a tubing (to be inserted in the groove 72 and not shown for illustration purposes) to (1 ) have one of its ends inserted in the opening 73 and (2) its other end to extend beyond the outer periphery of the entry point 66 for joining with inlets 74 of the suction section 56. The inlets 74 are arranged in a spaced apart relationship with respect to each other around the outer periphery of the exit point 64 of the discharge section 56.

[0078] Referring to figure 6b, the fact the one end of the tubing is inserted in the opening 73 permits fluid (from the second fluid pathway) to enter the tubing, follow through the tubing to exit the tubing at the inlet 74 in order to be delivered to the openings 78 of the indentation 60 of the suction section 56 for applying pressure to bearings 88 as will be described later herein.

[0079] Corresponding fluid pathways are defined within the suction section 56 extending from each inlet 74 to each respective opening 78. [0080] The grooves 72 and the inlets 74 are arranged around the outer peripheries of section 54 and 56 in such a manner that each groove 72 has a counterpart inlet 74 aligned with respect to each other. This allows for (when the sections 54 and 56 are joined together) the end section of the tubing (to be located within the grooves 72) extend beyond the outer periphery of section 54 for insertion in the counterpart inlet 74. In this manner, fluid paths are defined (by the tubing located within grooves 72) extending longitudinally from a location adjacent to the exit point 64 of the discharging section 54 to the inlets 74 located on the exit point 67 of the suction section 56. The tubing may be a conventional off-the-shelf tubing having an internal diameter of 2.7 mm.

[0081 ] Referring to figure 6b, figure 6b shows a front perspective view of the entry point 64 of the suction section 56.

[0082] As shown in figure 6b, the indention 60 comprises a rim 76. The rim 76 comprises a plurality of openings 78 arranged in a spaced apart relationship with respect to each other around the rim 76. Each inlet 74 (for the receiving the end section of each tubing located in grooves 72) is fluidly connected to a passage ending in each opening 78. In this manner, the fluid passing through each tubing is delivered to each counterpart inlet 74 and will exit the opening 78.

[0083] The fluid exiting the openings 78 is delivered to the bearing 88 mounted on the rotor 26 (see figure 7 being a schematic view of the rotor 26) in order to pressure the faces of the bearing 88 to keep them slightly apart to reduce friction. The pressure will only have slight lateral thrust so the openings 78 will cool and lubricate the bearing 88 whilst venturi effect will draw the fluid back into the discharge section 54.

[0084] The bearings 88 may be fully ceramic bearings or carbon/ceramic or stainless steels/Teflon® bearings. There may be provided a flow sensor in the jacket 34 to detect any interruption of fluid flow within the pump assembly 10. This is particular advantageous in the particular arrangement where the bearing 88 comprises carbon/ceramic bearing which need to operate only during the presence of fluid flow.

[0085] Referring to figure 7, figure 7 shows a perspective view of the rotor 26.

[0086] As shown in figure 7, the rotor 26 comprises a cylindrical hollow body 80 defining a passage 82 to allow fluid to enter the body 80 though one end 86 and exiting the other end 84 when the pump assembly 10 is in operation. Within the passage 82, is located a blade assembly 28 secured to the inner surface of the body 80 of the rotor 26 in order for the blade assembly 28 to rotate with the body 80 during operation of the stator 25 of the electric motor 24. In this manner, fluid entering the discharging section 54 is propelled by the blade assembly 28 and exits the suction section 56. An opening 90 (see figure 6b) is provided to permit cabling to be connected to the electric motor 24.

[0087] Further, as shown in figure 14, the body 80 of the rotor 26 comprises at each end 84 and 86 circular bearings 88 attached to the periphery of each end 84 and 86. The bearings 88 supporting rotation of the rotor 26 within the inner casing.

[0088] The ends 84 and 86 are open ends surrounded by the bearings 88 permitting fluid to transverse the rotor 26 during operation of the pump assembly 10. This arrangement, of the rotor 26 having opens with bearing 88 (in particular flat ring bearings 88 as shown in figure 7) surrounding the open ends 84 and 86 is particularly advantageous because it avoids the need of mechanical seals used in conventional pumps. It is known that the life span of these particular type of mechanical seals is relatively short in particular depending on the particular composition of the fluid and particles immersed within the fluid to be driven by the pumps.

[0089] Each indentation 60 comprises a sealing assembly (such as sealing assembly 132 shown in figures 20 to 22) to impede fluid leakage from the inner space to the exterior of the inner space.

[0090] Furthermore, the outer surface of the body 80 comprises pockets 92 arranged in a spaced apart relationship with respect to each other around the outer surface of the body 80.

[0091] The pockets 92 are adapted to receive permanent magnets 128 (see figure 19) for driving the rotational movement of the rotor 26 due to the electromagnetic field generated by the coils of the stator 25.

[0092] In the arrangement shown in figure 19, the pockets 90 comprises an open end and are configured for slideably receiving the magnets 128.

[0093] Referring now to figures 8 to 11 , figures 8 to 11 depict a particular arrangement of a pump assembly 94 in accordance with a second embodiment of the invention.

[0094] The pump assembly 94 comprises a receiving section 95 (adapted to receive the electric motor 24, as is shown in figure 11 ) and a centrifugal outlet 96 for receiving the fluid exiting the receiving section 95 and discharging the fluid (after having been propelled) through an outlet 97. This particular arrangement of pump assembly 94 shows that the electric motor 24 in accordance with the present embodiment of the invention (comprising the rotor assembly 16) may be retrofitted to other pumps such as centrifugal pumps.

[0095] The electric motor 24 contained in the receiving section 95 comprises a rotor 98 (see figure 9) having the rotor 26 described with reference to the present embodiments of the invention and an impeller 99 connected to the discharging end 100 of the rotor 26 for rotation together with the rotor 26 (during operation of the electric motor 24) and for receiving the propelled fluid exiting the rotor 26. The impeller 99 (acting just as an impeller of a centrifugal pump), upon receiving the propelled fluid, changes the direction of flow of the fluid in order for the fluid to exit the outlet 97 directed, in this particular arrangement, to a direction perpendicular to the fluid flow of the fluid when entering the pump assembly 94.

[0096] Referring now to figures 12 and 13, figures 12 and 13 depict a particular arrangement of a filter unit 102 in accordance with the first embodiment of the invention.

[0097] The filter unit 12 comprises a body 104 having a receiving section 106 and a discharging section 108. The receiving section 106 comprises an inlet 110 for receiving fluid to be filtered. The discharging section 108 comprises an outlet 112 for discharging the filtered fluid.

[0098] As shown in figure 13, each of the receiving and discharging sections 106 and 108 is configured as a hemispherical body having an open end 114. For fluidly connecting both sections 106 and 108, the sections 106 and 108 are joined together for defining the filter unit 12 as shown in figure 12 permitting fluid to traverse the filter unit 12 for filtering purposes of the fluid. Filtering occurs via a filter medium 116 sandwiched between the receiving and discharging sections 110 and 112. [0099] The particular arrangement shown in figures 2, 3, 12 and 13 depict the filter unit 12 as being configured as an ellipsoid. However, the receiving and discharging section 106 and 108 may configured as having any shape comprising open ends that may be joined for fluidly connecting the sections 110 and 112.

[0100] The pump assembly 10 and filter unit 10 may be fluidly connected with respect to each other (as shown in figure 3) to define a pump system 14 adapted to be immersed within a body of fluid that allows filtration of the fluid via the filter unit 12 and subsequent propulsion of the fluid via pump assembly 10.

[0101] Referring now to figures 14 to 18, figures 14 to 18 depict an alternative arrangement of the rotor assembly 16. The rotor assembly 16 comprises a blade assembly 28 as depicted in figure 17. In the arrangement shown in the figures 14 to 18, the blade assembly 28 is attached to one end of the rotor assembly 16 and the opposite end of the rotor assembly 16 comprises a cover 31 . The cover 31 may be configured as a flow straightener.

[0102] The blade assembly 28 may be releasably attached to the rotor assembly 16 permitting to use different type of blade assemblies 28 depending on the particular circumstances the pump assembly 10 may be used.

[0103] Referring now to figures 15 and 16, as shown in these figures, the rotor assembly 16 comprises a plurality of openings 118 arranged in a spaced apart relationship with respect to each other around the periphery 120 of the end of the rotor 26 comprising the blade assembly 28.

[0104] The plurality of openings 118 indent longitudinally into the body 122 of the rotor 26. This is particularly advantageous because it allows balancing the rotor 26 t in order that rotation of the body 122 of the rotor 26 occurs about the longitudinal axis of the rotor 25 avoiding precession of the rotor 26 during rotation of the rotor 26. In particular, the method for balancing the rotor 26 comprises the step of inserting, for example, sections of cylindrical rods (i.e. ballast) adapted to be received by the openings 118, at specific openings 118 for balancing the rotor 26. By repeating the steps of (1 ) adding the ballast to particular openings 118 and (2) rotating the rotor 16 to confirm whether the rotor 16 is properly balanced. The cylindrical rods may be stainless steel grub screws or heavy gauge stainless steel wire cut to precise, weighed lengths and pressed into place for the purpose of high-speed balancing. Referring to figure 19, figure 19 shows the rotor 26 shown in figures 14 and 15. As shown in figure 19, the outer surface 124 of the rotor 26 comprises a plurality of pockets 126 arranged in a spaced apart relationship with respect to each other around the body 122. In an arrangement, the pockets are pre-formed and adapted to receive curved magnets.

[0105] Each pocket 126 is adapted to receive a magnet 128 as shown in figure 19 defining the permanent magnet assembly of the rotor 26 for the rotor 26 to rotate when being immersed in the electromagnetic field generated by the stator 25 containing the rotor assembly 16. In a particular arrangement, the magnets 128 may be fully enclosed with the outer surface of the rotor 26.

[0106] As shown in figure 9, each pocket 90 comprises an open end 130 and is configured for slideably receiving the magnet 128.

[0107] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

[0108] For example, the Description of the Embodiment(s) describe, for succinctness purposes, a pump assembly 10 comprising all of the features of the first to sixth aspects of the invention included in the Summary of the Invention.

[0109] However, it is implied that each pump assembly 10 defined in one particular aspect of the invention may stand by itself without the features of the pump assemblies defined in any one or all of the other aspects of the invention excluding the particular aspect of the invention. Thus, the Description of the Embodiment(s) provides support to each particular pump assembly defined in the first to sixth aspects of the invention. This is particularly true because a person skilled in the art could, without undue experimentation, manufacture any pump assembly defined in any one of the first to sixth aspects of the invention.

[0110] Further, it should be appreciated that the scope of the invention is not limited to the scope of the embodiments disclosed. By way of example, the apparatus and method according to the invention may be suitable.

[0111] The language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based hereon. Accordingly, the disclosure of the embodiments of the invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.

[0112] Example embodiments are provided so that this disclosure will be thorough and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0113] Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

[0114] The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

[0115] Reference to positional descriptions and spatially relative terms), such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper” and the like, are to be taken in context of the embodiments depicted in the figures, and are not to be taken as limiting the invention to the literal interpretation of the term but rather as would be understood by the skilled addressee.

[0116] Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first”, “second”, and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0117] It will be understood that when an element is referred to as being “on”, “engaged”, “connected” or “coupled” to another element/layer, it may be directly on, engaged, connected or coupled to the other element/layer or intervening elements/layers may be present. Other words used to describe the relationship between elements/layers should be interpreted in a like fashion (e.g. “between”, “adjacent”). As used herein the term “and/or” includes any and all combinations of one or more of the associated listed items.

[0118] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprise”, “comprises”, “comprising”, “including”, and “having”, or variations thereof are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.