Coolant hub with integrated axis

Abstract

A thermal management module (100) includes a hub housing (10), and a first pump (20). The hub housing (10) includes a plurality of fluid flow channels (12) and a shaft (18). The hub housing (10) receives the first pump (20). The shaft (18) is received by a central aperture (28) of the first pump (20), and the shaft (18) is integrally formed with the hub housing (10).

Description

TECHNICAL FIELD

[0001] The present invention relates to coolant hub, more specifically, one configured for use in a vehicle such as an electric or a hybrid vehicle.BACKGROUND OF THE INVENTION

[0002] Generally, a thermal management module includes a fluid hub, a reservoir, at least one fluid machine, for example, and at least one fluid pump. Generally, the fluid hub is formed by joining two portions of plastic material by plastic welding, wherein at least one portion is configured with channels that define the fluid flow passages when the first and second portions are joined to each other. Further, the fluid hub configures multi-way valves controlled by a controller to selectively disrupt or establish fluid flow through the internal fluid flow passages for defining different cooling circuits and regulating fluid supply to the vehicle heat exchangers based on operating configuration of the multi-way valve that can be changed based on requirement. More specifically, the fluid hub configures several cooling circuits, wherein one or more cooling fluids are routed through the different cooling circuits to achieve different cooling based on requirements, while still maintaining fluid isolation between the cooling fluids flowing through the different cooling circuits. The fluid pumps drives the fluids to flow through the different cooling circuits that are configured based on operating configuration of the different valves configured in the fluid hub. The fluid hub receives fluid stored in the reservoir and selectively supplies the cooling fluids to the different heat exchangers through the different cooling circuits configured based on the operative configuration of the valves in the fluid hub. The fluid pumps are in fluid communication with the fluid flow channels to direct fluid to the heat exchangers.

[0003] Generally, the fluid pump comprises an electric motor. The motor includes a stator and a rotor. The rotor is fixedly connected to an impeller. The impeller interacts with a volute portion of the fluid hub. The volute portion has an aperture configuring fluid communication between the fluid pump and at least one fluid flow channels. As the rotor of the motor rotates, it also rotates the impeller driving fluid to at least one of the fluid flow channels through the aperture in the volute portion. The volute portion of the fluid hub has a centrally located receiving portion that houses a shaft. The rotor and the impeller have a central aperture configured to accommodate the shaft. Thus, when assembled, the shaft acts as a central axis of rotation for the rotor. Accordingly, during assembly, of the fluid pump to the fluid hub, an operator first mounts the shaft to the receiving portion of the volute using any suitable fastening means. Subsequently, the operator mounts the impeller and rotor to the shaft, secures the rotor and impeller to the shaft using a nut, then the stator is mounted on the rotor and finally a fluid pump cover is mounted to the stator and the cover is fastened to the fluid hub using suitable fastening means such as bolts.

[0004] However, during the assembly of the shaft to the hub, the axis of the shaft may remain misaligned with respect to the axis of the volute portion of the hub. Further, the weight of the rotor may add to the axial misalignment if the mounting of the shaft on the volute portion is improper. This results in a misaligned rotor and impeller with respect to the volute portion of the hub and the optimal functioning of the fluid pump is compromised resulting in efficiency losses.OBJECT OF THE INVENTION

[0005] An object of the invention is to allow proper centering of the shaft and as a result the rotor and impeller of the fluid pump with respect to the volute portion of the fluid hub.

[0006] Another objective of the invention is to reduce the steps required by an operator to assemble the fluid pump to the fluid hub.SUMMARY OF THE INVENTION

[0007] The present invention relates to a hub housing that includes a plurality of fluid flow channels and a shaft. The hub housing is configured to receive at least one first pump, with said shaft being adapted to be received by said first pump. The shaft is integrally formed with the hub housing.

[0008] Generally, the hub housing includes a first hub housing portion and a second hub housing portion. At least of the first hub housing portion and the second hub housing portion includes a volute portion.

[0009] Particularly, the central axis of the shaft is coaxial with a central axis of the volute portion.

[0010] Generally, the first hub housing portion and the second hub housing portion define a plurality of fluid flow channels.

[0011] Specifically, the hub housing is integrally formed with the shaft using a single material.

[0012] Alternatively, the first hub housing portion and the shaft are overmolded with respect to each other.

[0013] Particularly, the shaft is coated with a friction reducing material on its outer surface.

[0014] Alternatively, the shaft is of different material than the hub housing.

[0015] Generally, a thermal management module includes the hub housing. The thermal management module further includes at least one first pump secured to the hub housing and comprising an electric motor, the electric motor. The electric motor (22 further incudes a rotor assembly (222) and a stator assembly. The rotor assembly includes an impeller at least partially received within the hub housing. The rotor assembly includes an axial aperture adapted to receive the shaft to mount the rotor assembly on the shaft.

[0016] Particularly, the rotor assembly is mounted on the shaft by means of a fastener.

[0017] Generally, the rotor assembly is adapted to freely rotate over the shaft.

[0018] Additionally, the rotor assembly comprises a sleeve portion mounted on and adapted to freely rotate over the shaft.

[0019] Particularly, the fastener is integrated to at least one of the shaft and the rotor assembly.

[0020] Additionally, the invention further relates to a method of assembling the first pump to the coolant hub housing of the thermal management module. The method of assembling includes the steps of aligning an axial aperture of the rotor assembly of the first pump with a shaft that is integrally formed on the coolant hub housing. Further, the steps include inserting the shaft into the axial aperture by movement of at least the rotor assembly and the hub housing relative to each other, and restraining the relative axial motion of the rotor assembly with respect to the hub using the fastener.

[0021] Particularly, the method of assembling includes the steps of assembling at least one of a stator assembly and a cover of the first pump.

[0022] Specifically, the method of assembling includes the step of inserting the shaft into the axial aperture by translation of the rotor assembly and at least one of the stator assembly and a cover with respect to the hub housing.

[0023] More specifically, the fastener is integrated to at least one of the shaft and the rotor assembly.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other characteristics, details and advantages of the invention may be inferred from the description of the invention hereunder. A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying figures, wherein: FIG. 1 illustrates a schematic representation depicting a thermal management module in accordance with an embodiment of the present invention. FIG. 2 illustrates an exploded view depicting elements of the thermal management module of FIG. 1. FIG 3 illustrates an exploded view depicting the components of a hub housing of the thermal management module of FIG. 1. FIG 4 illustrates an isometric view of a first pump of the thermal management module of FIG. 1. FIG 5 illustrates an exploded view depicting the components of the first pump and a fastener of the thermal management module of FIG. 1. FIG 6A illustrates an isometric view of a rotor assembly of the first pump of the thermal management module of FIG. 1. FIG 6B illustrates a side view of a rotor assembly of the first pump of the thermal management module of FIG. 1. FIG 6C illustrates a front view of a rotor assembly of the first pump of the thermal management module of FIG. 1. FIG 7 illustrates a sectional view of the thermal management module of FIG. 2 along a section line XX' depicted in FIG 2. FIG 8 illustrates an enlarged view of a region of the fluid hub and pump depicted within a dotted line box AA in FIG. 7, wherein a rotor assembly is mounted on a shaft. FIG 9 illustrates an enlarged view of a region of the fluid hub and pump depicted within a dotted line box AA in FIG. 7, wherein the shaft includes a sleeve. DETAILED DESCRIPTION

[0025] It must be noted that the accompanying figures disclose the invention in a detailed enough way to be implemented, said figures helping to better define the invention, if need be. The invention should, however, not be limited to the embodiments disclosed in the description.

[0026] The present invention envisages a hub housing for a thermal management module, more specifically, a coolant hub for a thermal management module for heating and / or cooling a plurality of fluids in vehicular environment. The hub housing of the present invention overcomes the challenges of conventional hub housings in which the axis of a shaft for mounting a fluid pump can get misaligned with respect to the axis of a volute portion of the hub during assembly. The misalignment of the shaft results in a misaligned rotor and impeller with respect to the volute portion of the hub and consequent efficiency losses. The hub housing of the present invention includes a shaft that is integrally formed along with the hub housing, thereby preventing misalignment of the rotor and impeller with respect to the volute portion of the hub. The present invention is applicable to any coolant hub system used in automotive or non-automotive applications that is required to be efficient in operation and simple to assemble.

[0027] FIG. 1 illustrates an isometric view of a thermal management module 100 in accordance with an embodiment of the present invention.

[0028] In a preferred embodiment of the present invention, the thermal management module 100 comprises of a hub housing 10 and a first pump 20 adapted to drive flow of a coolant fluid within the hub housing 10. The first pump 20 is mounted on the hub housing 10 using suitable fasteners such as screws, bolts, rivets, click-locking elements or the like.

[0029] In an embodiment, the hub housing 10 is made using a moulded plastic material. However, the hub housing 10 can be made of any suitable material and process, without departing from the scope of the invention.

[0030] FIG. 2 illustrates an exploded view of the thermal management module 100 in accordance with an embodiment of the present invention depicting the components thereof. The thermal management module 100, in addition to the hub housing 10, the first pump 20 (as shown in FIG. 1), further comprises an actuator 40, a second pump 50 and a reservoir 60.

[0031] FIG. 3 illustrates an exploded view depicting the components of the hub housing 10 of the thermal management module 100. The hub housing 10 comprises a first hub housing portion 10a and a second hub housing portion 10b. At least one of the first hub housing portion 10a and the second hub housing portion 10b comprises a volute portion 16. The hub housing 10 further comprises a plurality of fluid flow channels 12 protruding outward and adapted for fluid flow, such as a coolant fluid, therein. In an embodiment, the second hub housing portion 10b defines the plurality of fluid flow channels 12. However, it should be appreciated, that either the first hub housing portion 10a or the second hub housing portion 10b or both, may have projections to define the plurality of fluid flow channels 12. Further, the hub housing 10 includes a shaft 18 that protrudes outward from the hub housing 10. The shaft 18 is centrally disposed with respect to the volute portion 16 receiving at least a portion of the pump 20, particularly, an impeller 222B (shown in FIG 6B). Specifically, the volute portion 16 of the hub housing 10 includes a plurality of joining legs 16a and a joining head 16b adapted to accommodate the shaft 18. The enlarged view of the joining legs 16a and the joining head 16b have been further illustrated in FIG. 8.

[0032] In an embodiment, hub housing 10 is adapted to receive the first pump 20, and the shaft 18 is adapted to be received by said first pump 20. The shaft 18 is integrally formed with the hub housing 10. More specifically, the volute 16 is adapted to receive at least a portion of the impeller 222b of the first pump 20. The impeller 222b rotates with a rotor body 222a (shown in FIG. 6B) of the pump 20 and interacts with the volute 16 to pressurise the fluid and drive the fluid to the fluid low channels 12.

[0033] In a preferred embodiment, the shaft 18 is integrally formed with the first hub housing portion 10a. Further, the central axis of the shaft 18 is coaxial with the central axis of the volute portion 16.

[0034] In an alternative embodiment, the shaft can be formed integrally with the second hub housing portion 10b.

[0035] In a preferred embodiment, the shaft 18 is made of different material than the hub housing 10. By way of example and without limitation, the hub housing 10 is made of a plastic molded material while the shaft 18 is made of a metal / alloy. By way of example, the shaft 18 is overmolded to the first hub housing portion 10a of the hub housing 10. More specifically the joining head 16b of the volute portion 16, is directly joined to the shaft 18 using overmolding. The embodiments of the joint between the shaft 18 and the joining head 16b will be discussed in greater detail later in this document in the description of FIG. 8.

[0036] Alternatively, the hub housing 10 may also be made of stamped sheet metal / alloy or a cast metal / alloy, or a combination thereof.

[0037] In another alternative embodiment, the hub housing 10 is integrally formed with the shaft 18 using a single material, such as plastic, using acasting process, injection molding process, or the like.

[0038] FIG. 4 illustrates an isometric view of the first pump 20. The first pump 20 includes a centrally located aperture 28. As will be discussed in further details later, the aperture 28 of the first pump 20 is adapted to accommodate the shaft 18 of the hub housing 10.

[0039] Fig. 5 illustrates an exploded view depicting the components of the first pump 20 along with a fastener 30. The first pump 20 is secured to the hub housing 10 and comprises an electric motor 22 and a cover 24. The motor 22, further includes a rotor assembly 222 and a stator assembly 224. Generally, the rotor assembly 222 of the motor 22 is first mounted to the shaft 18 and secured using the fastener 30. The rotor assembly 222 is adapted to freely rotate over the shaft 18 based on interaction between the rotor assembly 222 and the stator assembly 224. The stator assembly 224 circumferentially surrounds the rotor assembly 222 and generally includes wire windings. The cover 24 further surrounds the stator assembly 224 and is connected to the first hub housing portion 10a. The cover 24 comprises a housing 242 and an end cover 244 and connects to the first hub housing portion 10a around the volute portion 16. In a preferred embodiment, the cover 24 fluidically seals the motor 22 from the exterior.

[0040] FIG. 6A, 6B and 6C illustrate an isometric view, side view and a front view, respectively of the rotor assembly 222. The rotor assembly 222 includes a rotor body 222a, an impeller 222b and a connection portion 222c connecting the rotor body 222a to the impeller 222b. Specifically, the rotor assembly 222 comprises the aperture 28 (also shown in shown in FIG. 4) which is located centrally along a rotational axis of the rotor assembly 222. The axial aperture 28 of the rotor assembly 222 receives the shaft 18 to mount the rotor assembly 222 on the shaft 18.

[0041] FIG. 7 is a sectional view of the thermal management module as shown in FIG. 2 along a section line XX' depicted in FIG 2, depicting the first hub housing portion 10a, the second hub housing portion 10b, the rotor assembly 222, the shaft 18 and the fastener 30.

[0042] FIG. 8 shows an enlarged view of a portion of FIG. 7 bounded by dotted box AA. As further shown in FIG. 8, the impeller 222b is partially received within the hub housing 10. More specifically, the surface of the impeller 222b facing the volute 16 of the first hub housing portion 10a, has a curved conical surface and has a similar curvature as that of the volute 16. The joining head 16b of the volute 16 of the first hub housing portion 10a is overmolded over the shaft 18 and the rotor assembly 222. Thus the joining head 16b encapsulates the outer surface of the shaft 18 at one end.

[0043] In an alternative embodiment, the shaft 18 has an interior aperture (not shown) at one end and the joining head 16b is overmolded to the shaft 18 such that at least a portion of the joining head 16b is inside the interior aperture of the shaft 18.

[0044] In another embodiment, any suitable process such as an insert molding process, encapsulation, press-fitting, ultrasonic friction, welding, or the like, or any combination thereof, may be used to integrally form the shaft 18 with the joining head 16b of the hub housing 10.

[0045] Generally, the shaft 18 contacts the inner surface of the aperture 28 of the rotor assembly 222. The rotor assembly 222 is configured to rotate about the shaft 18. Thus, in an embodiment, the outer surface of the shaft 18, the inner surface of the aperture 28 of the rotor assembly 222, or both, may be coated with friction reducing material. By way of example, the friction reducing may include PTFE. The coating reduces friction between the outer surface of the shaft 18 and the rotor assembly 222 of the first pump 20. A further embodiment of the friction reduction technique will be discussed later in light of FIG. 9.

[0046] It must be understood that since the shaft 18 is integrally formed with the volute 16 of the hub housing 10, the shaft 18 is inherently coaxial with volute 16. This allows better centering of the rotor assembly 222 with respect to the volute 16. Furthermore, since the shaft 18 is integrally formed with the hub housing 10, an operator does not need to manually assemble the shaft 18 to the hub housing 10, reducing assembly time, effort and chances of misalignment.

[0047] The rotor assembly 222 is mounted on the shaft 18 by means of a fastener 30. The fastener 30 secures the rotor assembly 222 to the shaft 18 and prohibits any axial movement of the rotor assembly 22.

[0048] In an embodiment, the fastener 30 is a threaded fastener. Without limitation, the fastener 30 can be a hex nut, cap-nut, flange nut, or the like. A threaded end 18a of the shaft 18 protrudes out of the connection portion 222c in to the interior space defined by the rotor body 222a of the rotor assembly 222. With the rotor assembly 222 being fully inserted over the shaft 18, the fastener 30 is fastened over the threaded end 18a of the shaft 18 and torqued sufficiently to tighten the same and arrest axial motion of the rotor assembly 222.

[0049] In another alternative embodiment, the fastener 30 is integrated to the shaft 18 and / or the rotor assembly 222. By way of example, the fastener 30 may be in the form of a spring loaded detent having a slant surface (not shown) integrated or embedded in to the shaft 18. When the aperture 28 of the rotor assembly 222 slides over the shaft 18, the inner surface of the aperture 28 comes in contact with the slant surface of the detent compressing the springs. After the rotor assembly moves forward sufficiently, the fastener comes out of the aperture 28 and locks in place in place by the biasing action of the springs. This further reduces assembly time by eliminating the manual assembly of the fastener 30 (as in case of threaded fasteners). As may be understood by persons skilled in the art, a similar spring loaded detent may also be implemented on the rotor assembly 222 instead of the shaft 18.

[0050] It must be understood, that the rotor assembly 222 is able to freely rotate over the shaft 18. Thus, any suitable type of fastener that allows such a free rotational motion falls under the scope of this invention.

[0051] FIG. 9 illustrates a further embodiment wherein the rotor assembly 222 comprises a sleeve 222C is mounted on and freely rotates over the shaft 18. The sleeve 222C is made of friction reducing material and is disposed over the outer surface of the shaft 18 that faces the inner surface of the aperture 28 of the rotor assembly 222. Thus the friction between the rotor assembly 222 and the shaft 18 is greatly reduced, thus reducing wear and tear and NVH.

[0052] It must be noted that this invention, as a result of having the shaft 18 integrated to the coolant hub housing 10, enables easier and quicker assembly of the first pump 20 to the coolant hub housing 10, as compared to previous solutions. During the assembly of the first pump 20 to the coolant hub housing 10, the axial aperture 28 of the rotor assembly 222 of the first pump 20 is first aligned with the shaft 18 that is integrally formed on the coolant hub housing 10. Then, the shaft 18 is inserted into the axial aperture 28 by moving the rotor assembly 222 and the hub housing 10 close to each other. Then, the fastener 30 is used to restrain the relative axial motion of the rotor assembly 222 with respect to the hub 10, however, the rotor assembly 222 is free to rotate about the shaft 18. Finally, the stator assembly 224 is mounted over the rotor assembly 222 to complete the motor 22. Subsequently, the cover 24, comprising the housing 242 and the end cover 244 are used to cover the motor 22.

[0053] In an embodiment, the fastener 30 is a threaded fastener such as a cap nut, hex nut, or the like. Thus the fastener 30 is fastened to the threaded end 18a of the shaft 18 by tightening the fastener 30 over the threaded end 18a. It should be understood that any suitable fastening means can be utilized by a person skilled in the art for retaining the rotor assembly 22 to the shaft 18. In an embodiment, the step of inserting the shaft 18 into the axial aperture 28 is done by translating of the rotor assembly 222 and at least one of the stator assembly 224 and the cover 24 with respect to the hub housing 10. In another embodiment, the fastener 30 is integrated to the shaft 18 such as a spring loaded detent having a slant surface, as described earlier. It should be noted that if such a fastener 30 is implemented, the rotor assembly 222 can be simply slided over the slant surface of the spring loaded detent to click-lock the rotor assembly 222 in place eliminating the step of manually assembling and tightening threaded fasteners. Without limitation, such a fastener can be implemented on the rotor assembly 222 instead of the shaft 18.

Claims

1. A hub housing (10) comprising a plurality of fluid flow channels (12) and at least one shaft (18), said hub housing (10) being configured to receive at least a portion of at least one first pump (20), the shaft (18) being adapted to be received within said first pump (20), characterized in that the shaft (18) is integrally formed with the hub housing (10).

2. The hub housing (10) as claimed in the previous claim, wherein the hub housing (10) comprises a first hub housing portion (10a) and a second hub housing portion (10b), at least one of the first hub housing portion (10a) and the second hub housing portion (10b) comprises a volute portion (16).

3. The hub housing (10) as claimed in the previous claim wherein a central axis of the shaft (18) is coaxial with a central axis of the volute portion (16).

4. The hub housing (10) as claimed in any of the preceding claims, wherein the hub housing (10) is integrally formed with the shaft (18) using a single material.

5. The hub housing (10) as claimed in any of the preceding claims, in combination with claim 2, wherein the first hub housing portion (10a) and the shaft (18) are overmolded with respect to each other.

6. The hub housing (10) as claimed in any of the preceding claims, wherein the shaft (18) is of different material than the hub housing (10).

7. A thermal management module (100) comprising, • the hub housing (10) as claimed in any of the preceding claims, • at least one first pump (20) secured to the hub housing (10) and comprising an electric motor (22), the electric motor (22) comprising: ∘ a rotor assembly (222) comprises an impeller (222B) at least partially received within the hub housing (10), the rotor assembly (222) comprises an axial aperture (28) adapted to receive the shaft (18) to mount the rotor assembly (222) on the shaft (18); and ∘ a stator assembly (224).

8. The thermal management module (100) as claimed in claim 7, wherein the rotor assembly (222) is mounted on the shaft (18) by means of a fastener (30).

9. The thermal management module (100) as claimed in claim 7, wherein the rotor assembly (222) is adapted to freely rotate over the shaft (18).

10. The thermal management module (100) as claimed in claim 7, wherein the rotor assembly (222) comprises a sleeve (222C) mounted on and adapted to freely rotate over the shaft (18).

11. The thermal management module (100) as claimed in claim 8, wherein the fastener (30) is integrated to at least one of the shaft (18) and the rotor assembly (222).

12. A method of assembling a first pump (20) to a coolant hub housing (10) of a thermal management module (100) comprising the steps of - • aligning an axial aperture (28) of a rotor assembly (222) of the first pump (20) with a shaft (18) that is integrally formed on the coolant hub housing (10), • inserting the shaft (18) into the axial aperture (28) by movement of at least the rotor assembly (222) and the hub housing (10) relative to each other, • restraining the relative axial motion of the rotor assembly (222) with respect to the hub (10) using a fastener (30).

13. The method of assembling as claimed in the previous claim comprising the steps of assembling at least one of a stator assembly (224) and a cover (24) of the first pump (20).

14. The method of assembling as claimed in claim 12 wherein the step of inserting the shaft (18) into the axial aperture (28) comprises translation of the rotor assembly (222) with respect to at least one of the stator assembly (224) and a cover (24) with respect to the hub housing (10).

15. The method of assembling as claimed in claim 12 wherein the fastener (30) is integrated to at least one of the shaft (18) and the rotor assembly (222).

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