Pump assembly

Abstract

The invention is a pump assembly (1) for a cooling system of a vehicle operating assembly, the pump assembly extending relative to an axis (X-X) and comprising: i) a housing assembly (2) comprising a housing body (21) and an auxiliary body (22), the housing assembly defining a dry chamber (201) and a wet chamber (202); ii) an electric motor assembly (4) comprising a stator (41) housed in the dry cavity (201) and a rotor (42) housed in the wet cavity (202); iii) an impeller assembly (3) housed in the wet chamber (202), the impeller assembly comprising a blade body (30) and a control body (35) in which the rotor (42) is housed at least partially; iv) a shaft assembly (5), the majority of which is housed in the wet chamber (202), the shaft assembly comprising:-a shaft (50) extending along an axis (X-X), the shaft comprising a fixed end (500) engaging with the housing assembly (2) and comprising a free end (501); -a head (51) positioned at the free end (501), the head protruding radially from the shaft (50) to provide axial abutment to prevent axial movement of the impeller assembly (3); v) a cylindrical bushing (7) extending along the axis (X-X), freely rotatable and externally engaged by the rotor (42) and the impeller assembly (3). The pump assembly (1) comprises at least one cooling flow channel (6) extending substantially parallel to the axis (X-X), where the cooling flow channel (6) comprises a rotor section (64) passing through the rotor (42).

Description

Technical Field

[0001] This invention relates to a pump assembly for a vehicle cooling system. Background Technology

[0002] In this disclosure, the term "vehicle" refers to any means of transport without any limitation on type or size, such as motor vehicles or articulated vans.

[0003] In other words, the present invention relates to the automotive field, and more specifically, to a thermal management system for vehicle operating components or multiple operating systems.

[0004] Specifically, in this disclosure, "operating component" refers to a single part or a specific group of parts used to perform a particular operation required to move the vehicle. In a preferred embodiment, the "operating component" includes, for example, a thermally driven, electric, or hybrid motor assembly. In another variant, the "operating component" includes other vehicle components, namely, mechanical components such as a transmission assembly and electrical components such as a "battery assembly" or an "electric motor assembly."

[0005] In the prior art, there are several known implementations of pump assemblies for cooling systems of vehicle operating components, which differ in their actuation type.

[0006] Specifically, the pump assembly of the present invention is suited to this situation and has electric actuation. In other words, the pump assembly of the present invention includes at least one electric motor that controls the rotational movement of an impeller assembly housed therein, thereby controlling the drive of coolant flowing in a cooling system that is fluidly connected to the pump assembly.

[0007] Specifically, "coolant" is a water-based liquid, such as a solution containing water and ethylene glycol.

[0008] There are many known technical solutions for pump assemblies that include electric drives with electric motors, in which the rotor is "wet," meaning that the rotor is housed in the hydraulic section of the pump assembly, allowing the rotor to be accurately cooled by coolant driven by the impeller assembly.

[0009] A common problem associated with these implementations is the need to control the temperature of the pump assembly to avoid overheating of moving parts, and in particular, to promote cooling of electronic components such as control boards, stators and / or rotors. Summary of the Invention

[0010] Therefore, the object of the present invention is to provide a pump assembly for a cooling system of vehicle operating components to solve this typical problem in the prior art.

[0011] This objective is achieved by the pump assembly according to claim 1. This objective is also achieved by the method of manufacturing the pump assembly according to claim 12. The dependent claims relate to preferred construction variations with other advantageous aspects. Attached Figure Description

[0012] The object of the invention will now be described in detail with the aid of the accompanying drawings, in which: Figure 1 This is a side view of the pump assembly according to the present invention; Figure 2' and Figure 2'' The same cross-sectional view of the pump assembly as described in claim 1 is shown; Figure 2a This is an enlarged view of a region in Figure 2; Figure 3 It is a three-dimensional cross-sectional view of some components (i.e., impeller assembly, rotor and cylindrical bushing) assembled by co-molding; Figure 3a yes Figure 3 A three-dimensional view of the components when they are separated; Figure 4 yes Figure 1 A three-dimensional view of some components of the pump assembly when they are separated. Detailed Implementation

[0013] In the above figures, reference numeral 1 generally indicates a pump assembly for a cooling system used in vehicle operating components.

[0014] The pump assembly 1 of the present invention extends generally longitudinally relative to the axis XX.

[0015] According to the present invention, the pump assembly 1 includes a housing assembly 2.

[0016] Preferably, the housing assembly 2 is adapted to house at least most of the components of the pump assembly 1 of the present invention, as described below.

[0017] Preferably, the housing assembly 2 is fluidly connected to a flow channel of the cooling system in which coolant driven by the pump assembly 1 flows.

[0018] The housing assembly 2 includes a housing body 21 and an auxiliary body 22.

[0019] The housing assembly 2 defines a dry chamber 201 and a wet chamber 202 at the junction of the housing body 21 and the auxiliary body 22. In other words, coolant can enter the wet chamber 202 without restriction, while coolant is prevented from entering the dry chamber 201, which is sealed and isolated from the wet chamber 202.

[0020] The wet cavity 202 includes a central portion 202' along the axis XX, and the dry cavity 201 includes an annular portion 201' surrounding the central portion 202'.

[0021] In other words, according to the preferred embodiment, the housing body 21 and the auxiliary body 22 are sealed together. Preferably, a suitable gasket is provided on the housing body 21 or the auxiliary body 22.

[0022] According to a preferred embodiment, the housing assembly 2 can be assembled with a suitable component of the vehicle that forms system fluid flow channels. For example, the housing assembly can be assembled with a suitable system that houses operating components and / or valve assemblies. For example, the component includes a specific volute portion in which the pump assembly 1 operates.

[0023] According to a preferred embodiment, the housing assembly 2 includes a bottom wall.

[0024] Preferably, the bottom wall 220 is included in the auxiliary body 22.

[0025] Preferably, the bottom wall is included in the housing body 21.

[0026] According to a preferred embodiment, the bottom wall 220 includes a bottom disc-shaped member made of a metallic material.

[0027] Preferably, the bottom wall includes a support collar 225 that protrudes along axis XX into the central portion 202'.

[0028] According to a preferred embodiment, the housing body 21 is made of a metallic material, such as an aluminum alloy.

[0029] According to a preferred embodiment, the housing body 21 is made of a plastic material, such as PPS.

[0030] According to a preferred embodiment, the auxiliary body 22 is made of a plastic material, such as PPS.

[0031] According to a preferred embodiment, the bottom wall 220 includes a disc-shaped portion made of a metallic material.

[0032] Preferably, the support collar 225 is made of a metallic material, such as aluminum.

[0033] According to another preferred embodiment, the housing assembly 2 includes a volute body that is fluidly connected to the flow channels of the cooling system.

[0034] Preferably, the volute body is adapted to engage with the housing body 21 and / or with the auxiliary body 22. Preferably, at the junction of the volute body and the housing body 21 and / or the auxiliary body 22, the housing assembly 2 defines an impeller portion 202'' for accommodating the impeller 3 (described below) at the top of the wet cavity 202. Specifically, at the junction of the volute body and the housing body 21 and / or the auxiliary body 22, the wet cavity 202 in which the coolant flows is integrally defined.

[0035] According to a preferred embodiment, the volute body is made of a plastic material, such as PPS.

[0036] As mentioned above, the pump assembly 1 includes an impeller assembly 3 housed in the wet chamber 202.

[0037] The impeller assembly 3 includes a blade body 30 housed in the impeller section 202''.

[0038] According to a preferred embodiment, such as the one shown in the accompanying drawings, the pump assembly 1 further includes a blade cover 300 that can be assembled onto the blade body 30 of the impeller assembly 3. Depending on the shape of the blade body 3, the blade cover 300 may be a single piece, i.e., embedded in the impeller assembly 3, or the blade cover may be a separate component that engages with the blade body 3.

[0039] Preferably, the impeller assembly 3 is made of plastic material, preferably PPS.

[0040] In addition, the pump assembly 1 includes an electric motor assembly 4, which includes a stator 41 housed in the dry chamber 201 and a rotor 42 housed in the wet chamber 202.

[0041] The stator 41 is housed in the annular portion 201' and the rotor 42 is housed in the central portion 202'.

[0042] Preferably, the rotor 42 includes a rotor body 420.

[0043] Preferably, the rotor body 420 includes a plurality of laminated lamination elements.

[0044] Preferably, the rotor 42 includes rotor poles 421, for example, including specific magnetic elements.

[0045] According to a preferred embodiment, the laminated laminations define a suitable housing in which the rotor poles 421 are positioned.

[0046] According to the present invention, the pump assembly 1 includes a shaft assembly 5 substantially housed in the wet chamber 202, the shaft assembly comprising: - A shaft 50 extends along axis XX in the central portion 202', the shaft including a fixed end 500 that engages with housing assembly 2 and a free end 501; - Head 51, positioned at fixed end 500, protrudes radially from shaft 50 to provide axial abutment to prevent axial movement of impeller assembly 3.

[0047] According to a preferred embodiment, the shaft 50 and the head 51 are made as a single piece.

[0048] In addition, the pump assembly 1 includes a cylindrical bushing 7 extending along the axis XX, which is rotatable and externally engages with the rotor 42 and the impeller assembly 3.

[0049] According to the invention, the geometry of the pump assembly 1 is such that the rotation of the rotor 42 corresponds to the rotation of the cylindrical bushing 7 and the impeller assembly 3 about the shaft 5.

[0050] Preferably, the cylindrical bushing 7 is made of a metallic material, for example, sintered steel containing graphite.

[0051] Preferably, the cylindrical bushing 7 is made of pressed graphite.

[0052] Preferably, the cylindrical bushing 7 is made of graphite-filled resin.

[0053] Preferably, the rotor 42 is first assembled onto the cylindrical bushing 7. Then the impeller assembly 3 is molded over these components.

[0054] Preferably, the rotor 42 and the cylindrical bushing 7 are joined together by geometric interference. Preferably, the rotor 42 and the cylindrical bushing 7 are integrally interconnected.

[0055] According to the present invention, the impeller assembly 3 includes a control body 35 extending longitudinally from the blade body 30 along the axis XX.

[0056] Preferably, the control body 35 engages with the cylindrical bushing 7 and the rotor 42, thereby further securing the cylindrical bushing and the rotor.

[0057] In other words, the impeller assembly 3 is co-molded on the cylindrical bushing 7 and the rotor 42 to form a "combined component" in which the corresponding components form an integral whole.

[0058] According to a preferred embodiment, the rotor 42 is positioned on the cylindrical bushing 7, and after placing them in a suitable mold, the impeller assembly 3 is molded to obtain the "combined component". The "combined component" is then assembled onto the shaft 50 so that it can rotate freely.

[0059] According to a preferred embodiment, the control body 35 extends radially relative to the cylindrical bushing 7 and at least partially accommodates the rotor 42.

[0060] According to a preferred embodiment, the cylindrical bushing 7 has, for example, outer surfaces 71 on both sides of the rotor 42 adapted to facilitate engagement with the impeller assembly 3. For example, the outer surfaces 71 have grooves and / or rough portions.

[0061] According to the invention, the pump assembly 1 includes at least one cooling channel 6 adapted to allow recirculation of coolant. Preferably, the coolant flows toward the blade element 30 in the cooling channel 6.

[0062] Cooling channel 6 extends substantially parallel to axis XX.

[0063] The cooling channel 6 includes a rotor section 64 that passes through the rotor 42.

[0064] Preferably, the rotor segment 64 of the cooling channel 6 extends into the rotor body 420. In other words, the sheet element is shaped to present specific openings, thereby defining the rotor segment 64 within the laminated sheet element.

[0065] According to a preferred embodiment, the cooling channel 6 includes at least one impeller section 635', 635'', which passes through the impeller 3 in alignment with the rotor section 64.

[0066] Preferably, the cooling channel 6 includes a first impeller section 635' and a second impeller section 635'' located on opposite sides of the rotor section 64.

[0067] According to a preferred embodiment, the cross-sectional area of ​​the impeller sections 635' and 635'' is larger than the cross-sectional area of ​​the rotor section 64.

[0068] According to a preferred embodiment, the pump assembly 1 includes a plurality of cooling channels 6 spaced apart at equal angles.

[0069] Preferably, each cooling channel 6 is located in a region radially close to the cylindrical bushing 7.

[0070] Preferably, each cooling channel 6 is radially positioned between the cylindrical bushing 7 and the rotor pole 421.

[0071] According to a preferred embodiment, the pump assembly 1 further includes a washer 9 positioned axially between the cylindrical bushing 7 and the head 51.

[0072] Preferably, the washer 9 is adapted to minimize friction between the cylindrical bushing 7 and the head 51.

[0073] According to a preferred embodiment, the washer 9 is made of a material selected from ceramic materials.

[0074] Preferably, the washer 9 is made of aluminum oxide.

[0075] According to a preferred embodiment, the gasket 9 includes a radial groove 91 through which coolant flows until it reaches the shaft 50.

[0076] Preferably, the washer 9 includes a radial groove 91 on its upper surface facing the head 51.

[0077] Preferably, the washer 9 includes a radial groove 91 on the lower surface facing the cylindrical bushing 7.

[0078] Preferably, the shaft 50 has an annular groove 591 at the free end 501 near the head 51, in which coolant flows.

[0079] According to a preferred embodiment, the washer 9 is positioned such that the corner position of the washer remains fixed.

[0080] According to a preferred embodiment, the washer 9 engages with the shaft 50 to keep the angular position of the washer fixed.

[0081] Preferably, the shaft 50 is shaped near the head 51 (i.e., in the region near the free end 501) to achieve a positive connection with the washer 9 so as to hold the washer in a fixed angular position.

[0082] Preferably, the shaft 50 has a groove (or recess) in the region near the head 51, and the bushing 9 has a shaped hole, such as a slotted hole, to be geometrically coupled to the shaft section with the groove (or recess).

[0083] Preferably, the shaft 50 has a protruding radial portion in the proximal region, while the bushing 9 has a radial groove in which the protruding radial portion is accommodated.

[0084] According to these embodiments, the washer 9 is coupled to the shaft 50 in the region, and then the head 51 is mounted to the shaft 50 to hold the washer 9 in place.

[0085] According to another preferred embodiment, the washer 9 engages with the head 51 to keep the angular position of the washer fixed.

[0086] According to a preferred embodiment, the shaft 50 extends cantilevered from the housing assembly 2 along the axis XX to the head 51, with an extension length of shaft segment L.

[0087] According to a preferred embodiment, shaft 50 has a shaft diameter D.

[0088] According to a preferred embodiment, the head 51 has a head height I along the axis XX.

[0089] According to a preferred embodiment, the head 51 has a head diameter d.

[0090] Preferably, the ratio of shaft length L to head height I is between 10 and 25.

[0091] Preferably, the ratio of shaft diameter D to head diameter d is between 0.4 and 0.8.

[0092] Preferably, the ratio of shaft length L to head height I is between 15 and 20.

[0093] Preferably, the ratio of shaft diameter D to head diameter d is between 0.5 and 0.7.

[0094] Preferably, the size of the shaft segment L is between 25 mm and 30 mm.

[0095] Preferably, the shaft diameter D is between 4 mm and 6 mm.

[0096] According to a preferred embodiment, the shaft segment L extends from the support collar 225 to the head 51.

[0097] Preferably, the disc-shaped portion is made of metal, and the shaft 50 is also made of metal. Preferably, the shaft 50 and the disc-shaped portion are connected by force coupling.

[0098] As mentioned above, the present invention also relates to a method for manufacturing a pump assembly 1 having the aforementioned features.

[0099] Specifically, the present invention relates to a method for manufacturing a pump assembly 1, the method comprising the steps of: co-molding an impeller assembly 3 with a rotor 42 and a cylindrical bushing 7.

[0100] According to a preferred embodiment, the invention also relates to the following steps: positioning the rotor 42 on the cylindrical bushing 7 and housing them together in a suitable mold, in which the impeller assembly 3 is molded onto the "combined component".

[0101] Preferably, the suitable mold includes specific rod-shaped elements adapted to form the sections of the cooling channels.

[0102] Innovatively, this pump assembly largely achieves its intended purpose by overcoming typical problems of existing technologies.

[0103] Advantageously, the impeller assembly and rotor of the pump assembly are actually housed in the same chamber, so that both are wetted by the coolant.

[0104] Advantageously, this pump assembly provides a solution that improves the recirculation of cooling fluid.

[0105] Advantageously, the cylindrical bushing of the pump assembly can be effectively cooled.

[0106] Advantageously, the rotor of the pump assembly can be effectively cooled.

[0107] Advantageously, the flow of coolant in the rotor section involves inductive cooling of both the rotor body and the cylindrical bushing.

[0108] Advantageously, the impeller assembly of the pump assembly can be easily and precisely positioned relative to the shaft assembly, which is fixed in a defined position.

[0109] Advantageously, the presence of cooling channels in the rotor body makes the rotor body lighter and has less inertia.

[0110] Advantageously, cylindrical bushings are easy to manufacture and have a robust structure without grooves, channels, and / or openings.

[0111] Advantageously, the pump assembly has a cantilevered impeller assembly, requiring no additional axial support other than a single fixed end of the shaft.

[0112] Advantageously, the pump assembly can be used in constructions with a volute body or in constructions where the volute is located on other vehicle components.

[0113] Advantageously, the pump assembly operates quietly, and its solution addresses noise problems caused by factors such as inaccurate positioning of the vane elements or unwanted friction.

[0114] Advantageously, the pump assembly has a simple construction.

[0115] Advantageously, the pump assembly is easy to assemble.

[0116] It is obvious that, in order to meet possible needs, those skilled in the art can make changes to the invention described above, and all such changes are included within the scope of protection defined by the appended claims.

Claims

1. A pump assembly (1) for a cooling system of a vehicle operating assembly, the pump assembly extending with respect to an axis (X-X) and comprising: i) a housing assembly (2) comprising a housing body (21) and an auxiliary body (22), wherein the housing assembly (2) delimits a dry cavity (201) and a wet cavity (202) at the coupling of the housing body (21) and the auxiliary body (22), wherein the wet cavity (202) comprises a central portion (202') along the axis (X-X) and the dry cavity (201) comprises an annular portion (201') surrounding the central portion (202'); ii) an electric motor assembly (4) comprising a stator (41) housed in the annular portion (201') and a rotor (42) housed in the central portion (202'); iii) an impeller assembly (3) housed in the wet cavity (202), the impeller assembly comprising a blade body (30) and a control body (35), the rotor (42) being at least partially housed in the control body; iv) a shaft assembly (5), a major part of which is housed in the wet cavity (202), the shaft assembly comprising: - a shaft (50) extending along the axis (X-X) in the central portion (202'), the shaft comprising a fixed end (500) engaged with the housing assembly (2) and comprising a free end (501); - a head (51) positioned at the free end (501), the head radially protruding from the shaft (50) to provide an axial abutment to block axial movement of the impeller assembly (3); v) a cylindrical bushing (7) extending along the axis (X-X), the cylindrical bushing being freely rotatable and externally engaged by the rotor (42) and the impeller assembly (3); wherein the pump assembly (1) comprises at least one cooling flow channel (6) extending substantially parallel to the axis (X-X), wherein the cooling flow channel (6) comprises a rotor section (64) passing through the rotor (42).

2. The pump assembly (1) according to claim 1, wherein The cooling flow channel (6) comprises at least one impeller section (635', 635") passing through the impeller assembly (3) in alignment with the rotor section (64).

3. The pump assembly (1) according to claim 2, wherein The cooling flow channel (6) comprises a first impeller section (635') and a second impeller section (635") located on opposite sides of the rotor section (64).

4. The pump assembly (1) according to claim 2 or claim 3, wherein, The passage section of the impeller sections (635', 635") is greater than the passage section of the rotor section (64).

5. The pump assembly (1) according to any one of the preceding claims, the rotor (42) comprising a rotor body (420) and rotor magnetic poles (421) housed in the rotor body (420), wherein, The rotor body (420) comprises a plurality of laminated lamination elements, wherein the rotor section (64) extends through the rotor body (420), i.e. the rotor section extends through the laminated lamination elements.

6. The pump assembly (1) according to any one of the preceding claims, comprising a plurality of cooling flow channels (6) equally angularly spaced.

7. The pump assembly (1) according to any one of the preceding claims, wherein, The rotor (42) is engaged with the cylindrical bushing (7), for example the rotor is engaged with the cylindrical bushing by a force coupling.

8. The pump assembly (1) according to any one of the preceding claims, wherein Said control body (35) extends radially with respect to said cylindrical bushing (7) and at least partially houses said rotor (42).

9. Pump assembly (1) according to any one of the preceding claims, wherein Said impeller assembly (3) is co-moulded with said cylindrical bushing (7) and said rotor (42).

10. The pump assembly (1) according to any one of the preceding claims, wherein, Said casing assembly (2) comprises a bottom wall in which said fixed end (500) is engaged, wherein said bottom wall is comprised in said casing body (21) or in said auxiliary body (22).

11. Pump assembly (1) according to any one of the preceding claims, wherein Said casing assembly (2) comprises a volute body adapted to engage said casing body (21) and / or adapted to engage said auxiliary body (22), wherein, at the coupling of said volute body with said casing body (21) and / or with said auxiliary body (22), said casing assembly (2) delimits, at the top of said wet cavity (202), an impeller portion for housing said impeller (3).

12. A manufacturing method of a pump assembly (1) according to any one of the preceding claims, comprising the steps of: - co-moulding said impeller assembly (3) with said cylindrical bushing (7) and said rotor (42), thereby forming at least one said cooling channel (6).

13. The manufacturing method according to claim 12, by engaging said rotor (42) with said cylindrical bushing (7) through, for example, force coupling, and then co-moulding said impeller assembly (3) on said rotor (42) and said cylindrical bushing (7).

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