Bridge driving system

Abstract

The invention provides a bridge driving system. The bridge driving system comprises a shell; a rotor assembly (1); the stator assembly (2) is arranged on the radial outer side of the rotor assembly (1), and the stator assembly (2) comprises a stator core (21) and a winding (22); the two oil rings (3) are arranged at the two axial ends of the stator core (21) respectively, an annular oil cavity is defined by the oil rings (3), the inner wall of the shell and the end face of the stator core (21), each oil ring (3) comprises an inner end wall (31) close to the stator core (21) and a peripheral wall (32), the peripheral wall (32) is connected to the outer peripheral portion of the inner end wall (31) and provided with a winding outer side oil spraying hole (321), and the winding outer side oil spraying hole (321) is communicated with the inner end wall (31). Oil in the annular oil cavity can flow to the peripheral portion of the winding (22) through the winding outer side oil spraying hole (321), the inner end wall (31) is provided with an end wall radial oil channel (312), and the oil in the annular oil cavity can flow to the rotor assembly (1) through the end wall radial oil channel (312).

Description

Technical Field

[0001] This application belongs to the technical field of vehicle power systems, and particularly relates to an electric bridge drive system. Background Art

[0002] Compared with water-cooled motors, oil-cooled motors can directly contact the heat-generating components with oil. Therefore, most oil cooling systems have a structure of spraying oil to the end windings at both axial ends of the motor, and the stator core is provided with oil cooling channels.

[0003] The utility model patent CN212649253U discloses a motor oil cooling device, a motor assembly and a vehicle. The motor oil cooling device can make the cooling oil first flow through the oil ring at one end of the stator. A part of the oil liquid is sprayed onto the outer peripheral surface of the end winding through the oil holes on the oil ring, and another part of the oil liquid flows through the oil duct of the stator core to the oil ring at the other end of the stator, and then is sprayed onto the outer peripheral surface of the end winding at the other end of the stator through the oil holes on the other end oil ring.

[0004] Due to the inconsistent oil pressure around the oil rings at both ends of the stator, the oil flow rates ejected from the oil holes of the two oil rings are different, resulting in inconsistent cooling effects of the components at both axial ends of the motor. Specifically, referring to Figure 1 of this application, the oil liquid flowing to the left end of the stator first passes through the stator core, causing the oil liquid to be heated, and the cooling effect of the components at the left end of the motor is poor. In addition, the oil ejected from the oil ring can only be sprayed onto the outer periphery of the end winding, and it is difficult for other parts of the end winding and the rotor to directly contact the oil liquid. Therefore, the cooling effect of the motor is not good.

[0005] The utility model patent CN210404939U discloses a motor and a vehicle. The oil ejected from its oil ring can only be sprayed onto the outer periphery of the end winding, and it is difficult for other parts of the end winding and the rotor to directly contact the oil liquid. Therefore, the cooling effect of the motor is not good.

[0006] The utility model patent CN214412433U discloses an oil-cooled flat wire motor heat dissipation structure and a motor. A heat dissipation structure is provided above the end winding. The inside of the heat dissipation structure has several flow deflectors, and the flow deflectors can split the oil liquid to try to control the oil volume of each oil hole to be consistent. However, the flow deflectors do not isolate an independent space. After the inside of the heat dissipation structure is filled with oil liquid, it is difficult for the flow deflectors to achieve the expected effect. The oil ejected from the oil ring can only be sprayed onto the outer periphery of the end winding, and it is difficult for other parts of the end winding and the rotor to directly contact the oil liquid. Therefore, the cooling effect of the motor is not good. Summary of the Invention

[0007] This application aims to propose an electric bridge drive system, so that other parts except the outer peripheral surface of the end winding can also be allocated oil liquid for cooling, improving the cooling effect.

[0008] Embodiments of the present application provide a bridge drive system, including:

[0009] A housing;

[0010] A rotor assembly;

[0011] A stator assembly, which is disposed radially outside the rotor assembly. The stator assembly includes a stator core and windings; and

[0012] Two oil rings, which are respectively disposed at two axial ends of the stator core. An annular oil cavity is formed by the oil rings, the inner wall of the housing, and the end faces of the stator core. The oil rings include an inner end wall and a peripheral wall close to the stator core. The peripheral wall is connected to the outer peripheral portion of the inner end wall.

[0013] The peripheral wall is provided with oil injection holes outside the windings. The oil in the annular oil cavity can flow to the outer peripheral portion of the windings through the oil injection holes outside the windings.

[0014] The inner end wall is provided with radial oil channels in the end wall. The oil in the annular oil cavity can flow to the rotor assembly through the radial oil channels in the end wall.

[0015] In at least one possible embodiment, the radial oil channels in the end wall are provided with oil injection holes inside the windings. The oil injection holes inside the windings are disposed on the wall portion of the radial oil channels in the end wall that is axially outside the stator assembly, and are used for injecting oil to the middle portion in the radial direction of the windings.

[0016] In at least one possible embodiment, a plurality of partition plates are disposed on the outer peripheral surface of the peripheral wall. The plurality of partition plates are arranged along the circumferential direction of the oil ring. The plurality of partition plates divide the annular oil cavity into a plurality of independent arc-shaped oil cavities.

[0017] In at least one possible embodiment, a plurality of the oil injection holes outside the windings are disposed on the peripheral wall in each of the arc-shaped oil cavity regions.

[0018] The radial oil channels in the end wall are disposed on the inner end wall in each of the arc-shaped oil cavity regions.

[0019] In at least one possible embodiment, the stator core is provided with an oil cavity oil inlet channel, which axially penetrates the stator core along the axial direction of the stator core. The housing is provided with a housing oil inlet channel, and the housing oil inlet channel is communicated with the oil cavity oil inlet channel.

[0020] In at least one possible embodiment, a ring groove is disposed on the outer peripheral surface of the stator core. The ring groove is located at the middle position in the axial direction of the stator core. The ring groove truncates the oil cavity oil inlet channel into two parts, and the housing oil inlet channel is communicated with the ring groove.

[0021] In at least one possible embodiment, the inner end wall is provided with a plurality of winding holes, and the windings pass through the winding holes.

[0022] In at least one possible embodiment, the windings and the winding holes are in interference fit.

[0023] In at least one possible embodiment, within a single radial oil passage of the end wall, a plurality of oil injection holes inside the winding are arranged radially along the oil ring.

[0024] In at least one possible embodiment, the inner end wall abuts against the axial end face of the stator core, the peripheral wall abuts against the inner wall of the housing, and the peripheral wall, the inner wall of the housing and the axial end face of the stator core enclose the annular oil cavity, or

[0025] The inner end wall abuts against the axial end face of the stator core, the oil ring further includes an outer end wall away from the stator core, and the peripheral wall, the outer end wall, the inner wall of the housing and the axial end face of the stator core enclose the annular oil cavity.

[0026] By adopting the above technical solutions, the bridge drive system of the present application can achieve at least one of the following beneficial effects.

[0027] (1) The oil can flow through the radial oil passage of the end wall to the rotor assembly, so that both the rotor assembly and the end windings can directly contact the oil, and the cooling effect is better.

[0028] (2) Through the oil injection holes inside the winding, the oil can be directly sprayed onto the radial middle part of the winding, and the middle part in the radial direction of the end windings can directly contact the oil, and the cooling effect is better.

[0029] (3) By dividing a plurality of independent oil cavities along the circumferential direction of the oil ring, the flow rates of the oil sprayed out by each oil cavity are substantially the same and the amounts of oil are substantially equal, so that different positions of the cooled components can be cooled more evenly. Description of the Drawings

[0030] Figure 1 Shows a cross-sectional view of a bridge drive system according to an embodiment of the present application.

[0031] Figure 2 Shows a cross-sectional view of another section of a bridge drive system according to an embodiment of the present application.

[0032] Figure 3 Shows a partial enlarged view of a bridge drive system according to an embodiment of the present application.

[0033] Figure 4 Shows a schematic structural view of an oil ring of a bridge drive system according to an embodiment of the present application.

[0034] Figure 5 Shows a schematic structural diagram of a stator assembly and an oil ring of a bridge drive system according to an embodiment of the present application.

[0035] Figure 6 Shows along Figure 1 The cross-sectional view taken along line D-D in

[0036] Figure 7 Shows along Figure 2 The cross-sectional view taken along line E-E in

[0037] Figure 8 Shows along Figure 2 The cross-sectional view taken along line F-F in

[0038] Description of reference numerals

[0039] 100 Motor 200 Gearbox

[0040] 1 Rotor assembly

[0041] 2 Stator assembly 21 Stator core 211 Oil cavity oil inlet channel 212 Ring groove 22 Winding 221 End winding

[0042] 3 Oil ring

[0043] 31 Inner end wall 311 Winding hole 312 End wall radial oil duct 313 Inner winding injection hole

[0044] 32 Peripheral wall 321 Outer winding injection hole

[0045] 33 Partition

[0046] 34 Outer end wall

[0047] 4 Motor housing 41 Housing oil inlet channel

[0048] R1 Arc-shaped oil cavity

[0049] A Axial C Circumferential R Radial Detailed implementation manners

[0050] In order to more clearly elaborate the above-mentioned objects, features and advantages of the present application, the detailed implementation manners of the present application are described in detail in this part in conjunction with the accompanying drawings. In addition to the various implementation manners described in this part, the present application can also be implemented in other different ways. Without departing from the spirit of the present application, those skilled in the art can make corresponding improvements, deformations and replacements. Therefore, the present application is not limited by the specific embodiments disclosed in this part. The protection scope of the present application shall be subject to the claims.

[0051] AsFigures 1 to 8 As shown, an embodiment of the present application provides a bridge drive system, which includes a housing, a motor 100, and a gearbox 200. The gearbox 200 is connected to the motor 100. This bridge drive system can be used in pure electric vehicles or hybrid electric vehicles. The housing may include a motor housing 4 that defines a motor chamber and a gearbox housing that defines a gear chamber.

[0052] As Figure 1 and Figure 2 shown, the motor 100 includes a rotor assembly 1, a stator assembly 2, and an oil ring 3. The rotor assembly 1, the stator assembly 2, and the oil ring 3 are all disposed inside the motor housing 4. The rotor assembly 1 is mounted on a motor shaft, and the stator assembly 2 is disposed radially outside the rotor assembly 1.

[0053] The stator assembly 2 includes a stator core 21 and a winding 22. The winding 22 is mounted on the stator core 21. The ends of the winding 22 can extend from the axial two ends of the stator core 21, and the extended parts can be referred to as end windings 221. There may be two oil rings 3, and the two oil rings 3 are respectively disposed at the axial two ends of the stator core 21.

[0054] As Figure 2 and Figure 5 shown, the stator core 21 is provided with an oil chamber oil inlet channel 211, and the oil chamber oil inlet channel 211 can penetrate the stator core 21 along the axial direction A of the stator core 21. There are multiple oil chamber oil inlet channels 211, and the multiple oil chamber oil inlet channels 211 can be arranged along the circumferential direction C of the stator core 21. The oil chamber oil inlet channel 211 can be located radially outside the winding 22.

[0055] An annular groove 212 is provided on the outer peripheral surface of the stator core 21, and the annular groove 212 can be located at the middle position on the axial direction A of the stator core 21. The motor housing 4 is provided with a housing oil inlet channel 41, and the housing oil inlet channel 41 communicates with the annular groove 212. The annular groove 212 cuts off the oil chamber oil inlet channel 211 into two parts, so that the oil entering the inside of the motor housing 4 can flow from the annular groove 212 along the oil chamber oil inlet channel 211 to the axial two ends of the stator assembly 2, and is respectively supplied to the two oil rings 3 at the two ends of the stator assembly 2, and then the oil rings 3 further distribute the oil. In this way, the oil temperatures of the arc-shaped oil chambers R1 of the two oil rings 3 at the two ends of the stator assembly 2 can be kept substantially the same, and the cooling effects on the end windings 221 at the axial two ends can be kept substantially the same.

[0056] As Figure 3 and Figure 4 shown, the oil ring 3 (in particular, Figure 2 , Figure 5The oil ring on the left side (or the oil ring on one axial side) may include an inner end wall 31 and a circumferential wall 32 close to the stator core 21. The inner end wall 31 may be an annular flat plate extending along the radial direction R and the circumferential direction C of the motor 100. The circumferential wall 32 may be a cylindrical shape extending along the axial direction A and the circumferential direction C of the motor 100, and the circumferential wall 32 may be connected to the outer peripheral portion of the inner end wall 31. It can be understood that part or the whole circumferential wall may extend obliquely with respect to the axial direction A.

[0057] Referring to Figure 4 and Figure 5 , the oil ring 3 (for example, Figure 2 , Figure 5 the oil ring on the right side in the figure, or the oil ring on the other axial side) may further include an outer end wall 34 away from the stator core 21, and the outer end wall 34 may extend radially outward from the circumferential wall 32 to form an annular shape. Optionally, the outer peripheral portion of the outer end wall 34 may be bent toward the other axial side to form an edge, so as to increase the stability and sealing performance of the installation with the motor housing 4.

[0058] A plurality of partition plates 33 are connected to the circumferential wall 32 or the circumferential wall and the outer end wall 34. The partition plates 33 may be disposed on the outer peripheral surface of the circumferential wall 32. An annular oil chamber is formed by the circumferential wall 32 (or the circumferential wall 32 and the outer end wall 34), the inner wall of the motor housing 4, and the end face of the stator core 21. The plurality of partition plates 33 are arranged along the circumferential direction C of the oil ring 3, and the partition plates 33 can divide the annular oil chamber into a plurality of independent arc-shaped oil chambers R1, and the arc-shaped oil chambers R1 are not communicated with each other. The circumferential wall 32 is located radially inside the oil chamber oil inlet passage 211, and at least one oil chamber oil inlet passage 211 corresponds to each arc-shaped oil chamber R1. As Figure 5 shown, in this embodiment, 3 oil chamber oil inlet passages 211 correspond to each arc-shaped oil chamber R1. The partition plates 33 make each arc-shaped oil chamber R1 independent, and the oil in the arc-shaped oil chambers R1 will not interfere with each other, and the oil pressure can be kept substantially the same. Therefore, the flow rates of the oil discharged from the arc-shaped oil chambers R1 are also approximately the same, and the amounts of oil distributed from different arc-shaped oil chambers R1 (different circumferential regions of the oil ring 3) to the components to be cooled (including windings and rotor assemblies) are approximately equal, so that different positions of the components to be cooled can be cooled more evenly.

[0059] The inner end wall 31 may be provided with a plurality of winding holes 311. The winding holes 311 are arranged along the circumferential direction C of the inner end wall 31. The winding holes 311 may be strip-shaped extending along the radial direction R of the oil ring. The winding 22 may pass through the winding holes 311, so that the end winding 221 can be located radially inside the circumferential wall 32.

[0060] Optionally, the winding 22 and the winding holes 311 may be in interference fit, which can reduce oil leakage. The oil ring 3 and the stator assembly may be connected together by interference fit to form a stator assembly, which is convenient for transportation and management.

[0061] AsFigures 1 to 3 As shown, the peripheral wall 32 or the outer side wall 34 can abut against the inner wall of the housing, so that the inner end walls 31 of both oil rings 3 are in close contact with the stator core 21 to form a seal, preventing oil leakage from other positions except the oil holes (including the end wall radial oil passage 312 and the internal winding oil injection hole 313).

[0062] As Figure 3 and Figure 4 shown, the inner end wall 31 can be provided with an end wall radial oil passage 312. The end wall radial oil passage 312 can extend along the radial direction R of the oil ring 3, and the oil in the arc-shaped oil cavity R1 can flow to the rotor assembly 1 through the end wall radial oil passage 312. In this embodiment, the radially outer part of the end wall radial oil passage 312 can be an oil groove with an opening facing the stator core 21, and the radially inner part of the end wall radial oil passage 312 can be a through hole. Referring to Figure 4 、 Figure 8 , in the circumferential direction C, the end wall radial oil passage 312 can be arranged between the adjacent winding holes 311 and the windings (conductors) in the winding holes 311.

[0063] The wall of the end wall radial oil passage 312 is provided with an internal winding oil injection hole 313. The internal winding oil injection hole 313 can penetrate the inner end wall 31, and the internal winding oil injection hole 313 can be arranged on the wall of the end wall radial oil passage 312 on the outer side in the axial direction A of the motor 100. That is, the internal winding oil injection hole 313 of the oil ring 3 at the left end of the motor 100 is located on the left side wall of the end wall radial oil passage 312, and the internal winding oil injection hole 313 of the oil ring 3 at the right end of the motor 100 is located on the right side wall of the end wall radial oil passage 312. The oil flowing through the end wall radial oil passage 312 can spray oil to the axial middle part of the winding 22 through the internal winding oil injection hole 313. The internal winding oil injection hole 313 is located at the middle position in the radial direction R of the end winding 221. When observed along the axial direction A of the motor, the position of the internal winding oil injection hole 313 coincides with the winding 22, so that the oil can be directly sprayed to the radial middle part of the winding 22, and the cooling effect is better. One or more internal winding oil injection holes 313 can be arranged along the radial direction R of the oil ring 3, for example, two are arranged.

[0064] Optionally, the radially outer section of the end wall radial oil passage 312 can be in the form of a slotted groove, and the radially inner section of the end wall radial oil passage 312 can be in the form of a through hole. Of course, the present application does not limit the specific form of the end wall radial oil passage 312.

[0065] In the peripheral wall 32 within each arc-shaped oil chamber R1 region, there are oil injection holes 321 on the outer side of the winding. The oil in the arc-shaped oil chamber R1 can be distributed to the outer periphery of the end winding 221 through the oil injection holes 321 on the outer side of the winding. In the peripheral wall 32 within each arc-shaped oil chamber R1 region, there can be multiple oil injection holes 321 on the outer side of the winding. The multiple oil injection holes 321 can be arranged along the axial direction A of the oil ring 3 and along the circumferential direction C of the oil ring 3 simultaneously, so that the oil can be distributed to the outer periphery of the end winding 221 as evenly as possible.

[0066] The bridge drive system of the present application can have the following beneficial effects.

[0067] (1) The oil can flow through the end wall radial oil passage 312 to the rotor assembly 1, so that both the rotor assembly and the end winding can directly contact the oil, and the cooling effect is better.

[0068] (2) Through the oil injection holes 313 inside the winding, the oil can be directly sprayed onto the radial middle part of the winding 22, and the middle part in the radial direction of the end winding can directly contact the oil, and the cooling effect is better.

[0069] (3) By partitioning multiple independent arc-shaped oil chambers R1 along the circumferential direction C of the oil ring 3, the flow rates of the oil distributed and sprayed out from each arc-shaped oil chamber R1 are approximately the same, and the amounts of oil are approximately equal, which can make different positions of the cooled component be cooled more evenly.

[0070] It should be understood that at least some aspects or features of the above embodiments, examples or illustrations can be appropriately combined.

[0071] It can be understood that in the present application, when the number of components or members is not specifically limited, the number can be one or more, and here the multiple means two or more. For the case where the number of components or members shown in the drawings and / or described in the specification is a specific number such as two, three, four, etc., this specific number is usually exemplary rather than restrictive, and it can be understood as multiple, that is, two or more. However, this does not mean that the present application excludes the case of one.

[0072] In this application, unless otherwise clearly stated or defined, terms such as "installation", "assembly", "connection", "linkage", "attachment", "abutment", "communication", "interconnection", "conduction", "fixation", "fastening", etc. should be understood in a broad sense. For example, it can be direct or indirect. For example, regarding connection, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, which can be the internal communication between two components or the interaction relationship between two components, unless otherwise clearly stated or defined. For example, regarding communication / conduction, etc., it can be direct communication / conduction or indirect communication / conduction via an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0073] In this application, unless otherwise clearly stated or defined, a component being disposed in / installed in / located in / accommodated in / placed within another component can be either of the following two situations: a part or most of the component is located within the other component; and the component is completely accommodated within the other component.

[0074] Although the above embodiments have been used to describe this application in detail, for those skilled in the art, this application is obviously not limited to the embodiments described in this specification. This application can be modified and implemented as a variant embodiment without departing from the gist and scope of this application determined by the claims. Therefore, the descriptions in this specification are for illustrative purposes and do not have any restrictive meaning for this application.

Claims

1. A bridge drive system, characterized in that, Comprising: A housing; A rotor assembly (1); A stator assembly (2), the stator assembly (2) being disposed radially outside the rotor assembly (1), the stator assembly (2) including a stator core (21) and a winding (22); and Two oil rings (3), the two oil rings (3) being respectively disposed at two axial ends of the stator core (21), an annular oil chamber being defined by the oil rings (3), the inner wall of the housing, and the end faces of the stator core (21), the oil rings (3) including an inner end wall (31) close to the stator core (21) and a peripheral wall (32), the peripheral wall (32) being connected to the outer peripheral portion of the inner end wall (31), The peripheral wall (32) is provided with oil injection holes (321) outside the winding, and the oil in the annular oil chamber can flow to the outer peripheral portion of the winding (22) via the oil injection holes (321) outside the winding, The inner end wall (31) is provided with a radial oil passage (312) in the end wall, and the oil in the annular oil chamber can flow to the rotor assembly (1) via the radial oil passage (312) in the end wall.

2. The bridge drive system according to claim 1, characterized in that, The radial oil passage (312) in the end wall is provided with oil injection holes (313) inside the winding, and the oil injection holes (313) inside the winding are disposed on the wall portion of the radial oil passage (312) in the end wall that is located on the outer side in the axial direction (A) of the stator assembly (2) for injecting oil to the middle portion in the radial direction of the winding.

3. The bridge drive system according to claim 1, characterized in that, The outer peripheral surface of the peripheral wall (32) is provided with a plurality of partition plates (33), the plurality of partition plates (33) being arranged along the circumferential direction (C) of the oil ring (3), and the plurality of partition plates (33) dividing the annular oil chamber into a plurality of independent arc-shaped oil chambers (R1).

4. The bridge drive system according to claim 3, wherein A plurality of the oil injection holes (321) outside the winding are provided on the peripheral wall (32) in each of the arc-shaped oil chamber (R1) regions. The radial oil passage (312) in the end wall is provided on the inner end wall (31) in each of the arc-shaped oil chamber (R1) regions.

5. The bridge drive system according to claim 1, wherein The stator core (21) is provided with an oil chamber oil inlet passage (211), the oil chamber oil inlet passage (211) penetrating through the stator core (21) along the axial direction (A) of the stator core (21), and the housing is provided with a housing oil inlet passage (41), the housing oil inlet passage (41) being communicated with the oil chamber oil inlet passage (211).

6. The bridge drive system according to claim 5, characterized in that An annular groove (212) is provided on the outer peripheral surface of the stator core (21), the annular groove (212) being located at the middle position in the axial direction (A) of the stator core (21), the annular groove (212) truncating the oil chamber oil inlet passage (211) into two parts, and the housing oil inlet passage (41) being communicated with the annular groove (212).

7. The bridge drive system according to claim 1, characterized in that, The inner end wall (31) is provided with a plurality of winding holes (311), and the winding (22) passes through the winding holes (311).

8. The bridge drive system according to claim 7, wherein The winding (22) and the winding holes (311) are in interference fit.

9. The bridge drive system according to claim 2, characterized in that, In a single radial oil passage (312) in the end wall, a plurality of the oil injection holes (313) inside the winding are provided along the radial direction (R) of the oil ring (3).

10. The bridge drive system according to claim 1, characterized in that, The inner end wall (31) is in close contact with the axial end face of the stator core (21), the peripheral wall (32) abuts against the inner wall of the housing, and the peripheral wall (32), the inner wall of the housing, and the axial end face of the stator core (21) enclose the annular oil chamber, or The inner end wall (31) is in close contact with the axial end face of the stator core (21), the oil ring (3) further includes an outer end wall (34) away from the stator core (21), and the peripheral wall (32), the outer end wall (34), the inner wall of the housing, and the axial end face of the stator core (21) enclose the annular oil chamber.

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