Central integrated coaxial distributed double-motor electric drive axle shell and electric drive axle

Abstract

The utility model discloses a central integration coaxial distribution double-motor electric drive axle housing and electric drive axle, wherein the central integration coaxial distribution double-motor electric drive axle housing comprises a middle housing and two axle housings coaxially arranged at the two ends of the middle housing, the whole middle housing is in a hollow cylindrical structure, the two ends of the middle housing are open, and the two axle housings are arranged in the middle housing. An integrated cavity is formed in the middle shell, at least one hollow hole communicated with the interior of the integrated cavity is formed in the periphery of the middle shell, reinforcing ribs are formed on the peripheral face of the middle shell along the edge of each hollow hole, and the two axle housings are symmetrically arranged at the two ends of the middle shell. According to the scheme, the electric drive system has the advantages of being light in weight and low in cost, meanwhile, independent installation of the two sets of electric drive units and the dual-motor integrated coaxial bridge entering design achieve respective decoupling of the dual-motor bridge entering design, and the bearing risks of the speed reducer and the motors are reduced.

Description

Technical Field

[0001] The utility model relates to the field of electric drive axles, in particular to a central integrated coaxial distributed dual-motor electric drive axle housing and an electric drive axle. Background Art

[0002] A distributed electric drive axle is a mechatronic drive system designed for electric vehicles. Compared with an integrated electric drive axle, the distributed electric drive axle eliminates transmission components such as a clutch, a transmission, a drive shaft, a differential, and a half shaft. Drive motors are directly installed inside or near each drive wheel respectively to achieve separate wheel drive, having the advantages of high integration, small size, light weight, high efficiency, low energy consumption, high flexibility of the chassis, and high response speed.

[0003] Most of the existing layouts of distributed electric drive axles adopt a parallel-axis offset layout. For the Chinese invention patent with the publication number CN118061759A and the utility model patent with the authorization announcement number CN220429858U, both use dual motors to drive the left and right wheels respectively. Parallel axes (parallel intermediate shafts) are adopted inside the reducers between the motors and the wheels, and the motors and the reducers are not integrated into the axle, rather than a truly coaxial layout. Since the motors, the reducers, and the axle housing are fixed by flange surface bolts, complete decoupling cannot be achieved, that is, it is necessary to bear the entire axle load transmitted by the spring plates at both ends of the bridge head. This poses a bearing risk to the reducers and the motors, and there will be deflections and deformations. At the same time, the offset coaxial layout of the electric drive axle makes it impossible to use small-sized motors and reducers, resulting in a large space occupation and difficulty in achieving lightweight. Summary of the Utility Model

[0004] Therefore, to solve the above problems, the utility model provides a central integrated coaxial distributed dual-motor electric drive axle housing and an electric drive axle.

[0005] The utility model is realized by the following technical solutions:

[0006] A central integrated coaxial distributed dual-motor electric drive axle housing includes an intermediate housing and two axle housings coaxially arranged at both ends of the intermediate housing. The intermediate housing is integrally in a hollow cylindrical structure with openings at both ends and forms an integrated cavity inside. At least one hollow hole communicating with the inside of the integrated cavity is provided on the outer periphery of the intermediate housing. Reinforcing ribs are formed along the edge of each hollow hole on the outer peripheral surface of the intermediate housing. The two axle housings are symmetrically arranged at both ends of the intermediate housing. Each axle housing includes a hollow axle tube and a connecting portion integrally provided at the end of the axle tube. The connecting portion is connected to the end of the intermediate housing and a connecting cavity is formed inside the connecting portion. The connecting portion and both ends of the intermediate housing are fixedly connected by a first positioning mechanism.

[0007] Preferably, the first positioning mechanism includes a first flange surface provided at the connection end of the connection portion and the intermediate housing. An axially protruding first stop is provided along the inner circumference of the first flange surface. The first stop is embedded in the opening of the intermediate housing. The end faces of both ends of the intermediate housing are fitted with the first flange surfaces of the two connection portions and are fixed by a plurality of first bolts axially passing through therebetween. The first bolts are arranged at equal angles along the circumferences of the first flange surface and the intermediate housing.

[0008] Preferably, two groups of limiting bumps for limiting the electric drive unit are provided on the inner wall surface of the integrated cavity, and the two groups of limiting bumps are spaced apart.

[0009] The central integrated coaxial distributed dual-motor electric drive axle includes the central integrated coaxial distributed dual-motor electric drive axle housing as described in any one of the above.

[0010] Preferably, it includes a dual electric drive system. The dual electric drive system includes two electric drive units arranged coaxially and at intervals. The output end of each electric drive unit is provided in the axle housing at one end of the intermediate housing. Each electric drive unit includes a motor, a reducer, and an output shaft that are coaxially and drivingly connected. The motor and the reducer in the same electric drive unit are integrated in an electric drive housing. The output shaft is connected to the electric drive housing through a shaft sleeve and extends into the interior of one of the axle tubes.

[0011] Preferably, a second positioning mechanism is provided between the axle housing and the electric drive housing of its corresponding electric drive unit. The second positioning mechanism includes a second stop provided on the inner wall surface of the connection portion, and the second stop abuts against the end of the shaft sleeve.

[0012] Preferably, a second flange surface is also coaxially provided in the connection cavity of the connection portion. A third flange surface is provided on the electric drive housing. A third stop is axially protruded along the inner circumference of the third flange surface. The third stop is embedded in the inner circumference of the second flange surface. The second flange surface and the third flange surface are fixed by a plurality of second bolts axially passing through therebetween. The second bolts are arranged at equal angles along the circumferences of the second flange surface and the third flange surface.

[0013] Preferably, it further includes a controller provided on the top of the intermediate housing, and the controller is connected to the intermediate housing through a suspension rubber bushing.

[0014] Preferably, the outer circumference of the intermediate housing includes at least a first hollow hole. The three-phase interfaces of the motors in the two electric drive units are all located in the first hollow hole. A high-voltage plug connector trailing wire is connected to the bottom of the controller. The high-voltage plug connector trailing wire passes through the first hollow hole and is connected to the three-phase interfaces of the motors in the two electric drive units.

[0015] Preferably, a second hollow hole is further provided on the outer periphery of the intermediate housing, and the motors in the two electric drive units are both connected with a heat dissipation mechanism, and the heat dissipation mechanism exposes out of the intermediate housing from the second hollow hole.

[0016] The beneficial effects of the technical solution of the present utility model are mainly reflected in:

[0017] 1. For the motor and the reducer of the electric drive axle in this solution, the integration into the axle realizes a highly integrated central integrated coaxial arrangement. On the one hand, the distributed electric drive axle cancels transmission components such as the clutch, transmission, drive shaft, differential, and half shaft, and is applicable to small-sized motors and reducers, making the electric drive system have the advantages of light weight and low cost. On the other hand, the highly integrated coaxial arrangement minimizes the Z-direction space occupation as much as possible, simplifies the overall structure of the electric drive axle housing, and reduces the overall volume of the electric drive axle.

[0018] 2. The housing of the central integrated coaxial distributed dual-motor electric drive axle includes an intermediate housing and axle housings symmetrically arranged at both ends of the intermediate housing. Among them, an integrated cavity is formed inside the intermediate housing, and a connection cavity for accommodating the reducer is further provided in the connection part of the axle housing. The two electric drive units are respectively fixedly connected to the two side axle housings through multiple groups of positioning mechanisms, and at the same time are respectively fixedly connected to the intermediate housing. On the premise of effective fixation, the independent installation of the two electric drive units and the design of the dual-motor integrated coaxial into the axle are realized, achieving the decoupling of the two dual-motor into the axle designs, avoiding the shear and bending loads caused by the axle load, and avoiding the direct influence on the electric drive system when the overall axle load acts, reducing the bearing risks of the reducer and the motor.

[0019] 3. The controller is installed on the top of the intermediate housing to realize the integration into the axle. The assembly points of the two are connected by a suspension rubber bushing, and the controller is connected to the three-phase interface of the motor through a high-voltage plug-in wire, thus avoiding hard connection, ensuring the decoupling of the controller and the electric drive system during operation, and avoiding damage to the connection between the controller and the three-phase interface of the motor due to hard assembly.

[0020] 4. The hollow holes formed on the outer periphery of the intermediate housing can, on the one hand, facilitate the electrical connection between the controller and the motor, and on the other hand, can be used for the layout of the heat dissipation mechanism of the motor. In addition, the setting of the hollow holes can increase the heat dissipation area and reduce the weight of the intermediate housing, further realizing the lightweight design of the electric drive axle housing and the overall electric drive axle. Description of the Drawings

[0021] Figure 1 is a perspective view of the housing of the central integrated coaxial distributed dual-motor electric drive axle;

[0022] Figure 2It is the front view of the central integrated coaxial distributed dual-motor electric drive axle housing;

[0023] Figure 3 It is the sectional view of the central integrated coaxial distributed dual-motor electric drive axle housing;

[0024] Figure 4 It is Figure 3 the enlarged view of part A in

[0025] Figure 5 It is the front view of the central integrated coaxial distributed dual-motor electric drive axle;

[0026] Figure 6 It is the sectional view of the central integrated coaxial distributed dual-motor electric drive axle;

[0027] Figure 7 It is Figure 6 the enlarged view of part B in

[0028] Figure 8 It is the front view of the controller and the dual-electric drive system (the high-voltage plug-in wire and the output shaft are omitted). Detailed implementation manners

[0029] To clearly and detailedly show the purpose, advantages and features of the present utility model, it will be illustrated and explained through the non-restrictive description of the following preferred embodiments. This embodiment is only a typical example of applying the technical solution of the present utility model, and all technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present utility model.

[0030] At the same time, it is stated that in the description of the solution, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "front", "rear", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of description and simplification of the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model.

[0031] In addition, the terms "first" and "second" in this solution are only used for descriptive purposes, and cannot be understood as indicating or implying the ranking of importance, or implicitly indicating the quantity of the technical features shown. Therefore, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the present utility model, the meaning of "a plurality" is two or more, unless otherwise clearly and specifically defined.

[0032] The present utility model discloses a central integrated coaxial distributed dual-motor electric drive axle housing, as Figures 1 - 4As shown, it includes an intermediate housing 1 and two axle housings 2 coaxially arranged at both ends of the intermediate housing 1. One end of each of the two axle housings 2 is connected to the intermediate housing 1, and the other end is connected to the wheel end.

[0033] As Figures 1 - 3 shown, the intermediate housing 1 is integrally in a hollow cylindrical structure with openings at both ends, and an integrated cavity 103 is formed inside. The integrated cavity 103 is used to accommodate part of the structure of the dual electric drive system. At least one hollow hole 101 communicating with the inside of the integrated cavity 103 is provided on the outer periphery of the intermediate housing 1. The arrangement of the hollow holes 101 can not only achieve the light weight of the intermediate housing 1, but also provide a connection channel for some external accessories to the integrated cavity 103. The shape, number and arrangement position of the hollow holes 101 can be adjusted according to actual needs. In some embodiments, the shapes of the hollow holes 101 on the outer periphery of the intermediate housing 1 are different, and the adjacent hollow holes 101 are irregularly arranged. In a preferred embodiment, a plurality of hollow holes 101 are arranged at equal angles on the outer periphery of the intermediate housing 1, and the shape and size of each hollow hole 101 are the same, which will not be elaborated here.

[0034] While achieving the light weight of the intermediate housing 1, in order to ensure the support strength of the structure of the intermediate housing 1, reinforcing ribs 102 are formed along the edge of each hollow hole 101 on the outer peripheral surface of the intermediate housing 1.

[0035] The two axle housings 2 are symmetrically arranged at both ends of the intermediate housing 1. Each axle housing 2 includes a hollow axle tube 201 and a connecting portion 202 integrally provided at the end of the axle tube 201. The connecting portion 202 is connected to the end of the intermediate housing 1, and a connecting cavity is formed inside the connecting portion 202. In a preferred embodiment, the connecting portion 202 transitions from the end of the above-mentioned axle tube 201 towards the intermediate housing 1, and ensures that the outer diameter of the connecting portion 202 matches the outer diameters of both ends of the intermediate housing 1.

[0036] As Figure 4As shown, the connecting portion 202 is fixedly connected to both ends of the intermediate housing 1 through a first positioning mechanism. In one embodiment, the first positioning mechanism includes a first flange surface 2021 provided at the connecting end of the connecting portion 202 and the intermediate housing 1. An axially protruding first stop 2022 is provided along the inner circumference of the first flange surface 2021. The first stop 2022 is embedded in the opening of the intermediate housing 1, and the end faces of both ends of the intermediate housing 1 are fitted to the first flange surfaces 2021 of the two connecting portions 202. Screw holes are provided in a one-to-one correspondence on the first flange surface 2021 and the end face of the intermediate housing 1, and the connecting portion 202 and the intermediate housing 1 are fixed by a plurality of first bolts 8 axially passing between the first flange surface 2021 and the end face of the intermediate housing 1. The first bolts 8 are arranged at equal angles in the circumferential direction of the first flange surface 2021 and the intermediate housing 1, thereby ensuring the stability of the radial and axial assembly of the two at the same time.

[0037] As Figures 1 - 3 shown, in some embodiments, two groups of limiting bumps 104 for limiting the electric drive unit 4 are provided on the inner wall surface of the integrated cavity 103. The two groups of limiting bumps 104 are arranged at intervals. Specifically, the two groups of limiting bumps 104 are respectively used to limit the positions of the two electric drive units 4 in the double electric drive system in the integrated cavity 103. Since the two groups of limiting bumps 104 are arranged at intervals, a certain distance can be ensured between the two sets of electric drive units 4, realizing the integration of the two sets of electric drive units 4 into the bridge while decoupling them from each other. In one embodiment, each group of limiting bumps 104 includes two spaced-apart limiting bumps 104, and the two limiting bumps 104 are respectively arranged on both sides of a hollow hole 101. A limiting screw hole may be provided in the limiting bump 104, so that when the electric drive unit 4 is assembled into the bridge, it is fixed to the two limiting bumps 104 by screws / bolts.

[0038] The present utility model also discloses a central integrated coaxial distributed dual-motor electric drive axle, as Figures 5 - 8 shown, including the central integrated coaxial distributed dual-motor electric drive axle housing described in any one of the above.

[0039] In some embodiments, the central integrated coaxial distributed dual-motor electric drive axle includes a double electric drive system. The double electric drive system includes two coaxial and spaced-apart electric drive units 4. The output end of each electric drive unit 4 is arranged in the axle housing 2 at one end of the intermediate housing 1. On the one hand, it ensures that the axle housing 2 and the intermediate housing 1 jointly bear the double electric drive system. On the other hand, in the double electric drive system, a single electric drive unit 4 is cooperatively loaded by a corresponding axle housing 2 and intermediate housing 1.

[0040] Among them, each electric drive unit 4 includes a motor 401, a reducer 402 and an output shaft (not shown in the figure) that are coaxial and transmission-connected. The motor 401 and the reducer 402 within the same electric drive unit 4 are integrated within an electric drive housing. The output shaft is connected to the electric drive housing through a shaft sleeve 9 and extends to the outside of the electric drive housing. When the electric drive unit 4 is assembled within the electric drive axle housing 2, the output shaft extends into the interior of one of the axle tubes 201 and ultimately connects to the wheel end.

[0041] As Figure 6 , Figure 7 shown, in some embodiments, a second positioning mechanism is provided between the axle housing 2 and the electric drive housing of its corresponding electric drive unit 4. The second positioning mechanism includes a second stop 2024 provided on the inner wall surface of the connecting portion 202. The second stop 2024 abuts against the end of the shaft sleeve 9. In a preferred embodiment, the second stop 2024 is located at the connection between the connecting portion 202 and the axle tube 201, and the second stop 2024 is a protruding annular stop provided on the inner wall surface of the connecting portion 202. When the electric drive unit 4 is assembled within the electric drive axle housing 2, one end of the shaft sleeve 9 outside the output shaft abuts against the surface of the second stop 2024, thereby realizing the fixation of the output shaft of the electric drive unit 4 by the axle housing 2.

[0042] In some embodiments, a third positioning mechanism is further provided between the connecting portion 202 and the electric drive housing. The third positioning mechanism includes a second flange surface 2023 coaxially provided within the connection cavity, and a third flange surface 404 provided on the electric drive housing. A third stop 405 protrudes axially along the inner circumference of the third flange surface 404. The third stop 405 is embedded within the inner circumference of the second flange surface 2023. The second flange surface 2023 and the third flange surface 404 are fixed by a number of second bolts 10 axially passing through the two. The second bolts 10 are arranged at equal angles along the circumferences of the second flange surface 2023 and the third flange surface 404, thereby ensuring the stability of their assembly.

[0043] In the above embodiments, the fixation of one set of electric drive units 4 is realized by the second positioning mechanism and the third positioning mechanism of the axle housing 2, and the fixation of two sets of electric drive units 4 is realized by the two sets of limiting bumps 104 of the intermediate housing 1. Therefore, through the mutual cooperation of the intermediate housing 1 and the two axle housings 2, the independent installation of the two sets of electric drive units 4 and the design of integrating two motors 401 coaxially into the axle are realized, achieving the decoupling of the two motors 401 in the axle design, avoiding the shear and bending loads caused by excessive axle loads, avoiding the direct influence on the electric drive system when the overall axle load acts, and reducing the bearing risks of the reducer 402 and the motor 401.

[0044] AsFigures 5 - 8 As shown in the figure, in some embodiments, it further includes a controller 3 disposed on the top of the intermediate housing 1. The controller 3 is connected to the intermediate housing 1 through a suspension rubber bushing 6, so as to achieve soft assembly of the controller 3 on the intermediate housing 1 while realizing the integration of the controller 3, ensuring decoupling of the controller 3 and the electric drive system during operation, and avoiding damage to the connection points of the controller 3 and the three-phase interfaces of the motor 401 due to hard assembly. Among them, the suspension rubber bushing 6 can adopt any existing suspension bushing structure, which will not be elaborated here. One end of the suspension rubber bushing 6 is connected to the housing of the controller 3, and the other end is connected to the outer surface of the intermediate housing 1. The number of suspension rubber bushings 6 between the controller 3 and the intermediate housing 1 can be adjusted according to actual needs. To ensure the stability of the controller 3 fixation, at least two or more suspension rubber bushings 6 should be provided.

[0045] As Figure 5 shown in the figure, in some embodiments, the outer periphery of the intermediate housing 1 at least includes a first hollow hole. The three-phase interfaces of the motors 401 in the two electric drive units 4 are both located in the first hollow hole. A high-voltage plug-in wire 5 is connected to the bottom of the controller 3. The high-voltage plug-in wire 5 passes through the first hollow hole and is connected to the three-phase interfaces of the motors 401 in the two electric drive units 4. By adopting the connection method of the high-voltage plug-in wire 5, hard connection at the interface is avoided, so that when the dual electric drive system operates and is subjected to vibration load, the controller 3 and the electric drive system are decoupled, and damage to the connection points of the controller 3 and the three-phase interfaces of the motor 401 due to fixed connection is avoided.

[0046] In some embodiments, a second hollow hole is further provided on the outer periphery of the intermediate housing 1. The motors 401 in the two electric drive units 4 are both connected with a heat dissipation mechanism 7 (not shown in the figure). The heat dissipation mechanism 7 exposes from the second hollow hole to the outside of the intermediate housing 1. In one embodiment, the heat dissipation mechanism 7 includes two oil coolers disposed on the two motors 401. An oil cooling water channel is integrated inside the oil cooler. The oil cooling water channel is communicated with the cooling water channel of the motor 401, and the oil cooler is provided with a water outlet nozzle communicated with the cooling water channel. The water outlet nozzle exposes outside the second hollow hole, which is convenient for connecting an external pipeline and discharging the cooling medium. The specific structures of the oil cooler and the cooling water channels inside the motor 401 can refer to the prior art and will not be elaborated here.

[0047] The present utility model has multiple implementation manners. All technical solutions formed by equivalent transformation or equivalent substitution fall within the protection scope of the present utility model.

Claims

1. A centrally integrated coaxial distributed dual-motor electric drive axle housing, comprising an intermediate housing and two axle housings coaxially arranged at both ends of the intermediate housing, characterized in that: The intermediate shell is a hollow cylindrical structure as a whole, with openings at both ends and an integrated cavity formed inside. The outer periphery of the intermediate shell is provided with at least one hollow hole communicating with the interior of the integrated cavity. Reinforcing ribs are formed on the outer peripheral surface of the intermediate shell along the edge of each hollow hole. Two bridge shells are symmetrically arranged at the two ends of the intermediate shell. The bridge shells each include a hollow bridge tube and a connecting part integrally arranged at the end of the bridge tube. The connecting part is connected to the end of the intermediate shell and a connecting cavity is formed inside the connecting part. The connecting part is fixedly connected to the two ends of the intermediate shell by a first positioning mechanism.

2. The centrally integrated coaxial distributed dual-motor electric drive axle housing according to claim 1 is characterized by: The first positioning mechanism includes a first flange surface arranged at the connecting end of the connecting part and the intermediate shell, and the inner circumference of the first flange surface is axially protruding with a first stop, and the first stop is embedded in the opening of the intermediate shell. The end surfaces of both ends of the intermediate shell are fitted with the first flange surfaces of the two connecting parts and are fixed by a plurality of first bolts axially penetrated therebetween, and the first bolts are arranged at equal angles along the circumference of the first flange surface and the intermediate shell.

3. The centrally integrated coaxial distributed dual-motor electric drive axle housing according to claim 1 is characterized by: Two groups of limiting protrusions for limiting the electric drive unit are arranged on the inner wall surface of the integrated cavity, and the two groups of limiting protrusions are arranged at intervals.

4. Central integrated coaxial distributed dual-motor electric drive axle, characterized by: It comprises a centrally integrated coaxial distributed dual-motor electric drive axle housing as described in any one of claims 1-3.

5. The centrally integrated coaxial distributed dual-motor electric drive axle according to claim 4 is characterized by: It includes a dual electric drive system, which includes two coaxial and spaced electric drive units, the output end of each electric drive unit is arranged in a bridge housing at one end of the intermediate housing, each electric drive unit includes a coaxial and transmission-connected motor, a reducer and an output shaft, the motor and reducer in the same electric drive unit are integrated in an electric drive housing, the output shaft is connected to the electric drive housing through a bushing and extends to the interior of one of the bridge tubes.

6. The centrally integrated coaxial distributed dual-motor electric drive axle according to claim 5 is characterized by: A second positioning mechanism is provided between the bridge housing and the electric drive housing of the corresponding electric drive unit, and the second positioning mechanism includes a second stopper provided on the inner wall surface of the connecting portion, and the second stopper abuts against the end of the bushing.

7. The centrally integrated coaxial distributed dual-motor electric drive axle according to claim 6 is characterized by: A second flange surface is coaxially arranged in the connecting cavity of the connecting part, and a third flange surface is arranged on the electric drive housing. A third stop is axially protruding on the inner circumference of the third flange surface, and the third stop is embedded in the inner circumference of the second flange surface. The second flange surface and the third flange surface are fixed by a plurality of second bolts axially arranged therebetween, and the second bolts are arranged at equal angles along the circumference of the second flange surface and the third flange surface.

8. The centrally integrated coaxial distributed dual-motor electric drive axle according to claim 5 is characterized by: It also includes a controller arranged on the top of the intermediate shell, and the controller is connected to the intermediate shell through a suspension rubber bushing.

9. The centrally integrated coaxial distributed dual-motor electric drive axle according to claim 8 is characterized by: The outer periphery of the intermediate shell includes at least a first hollow hole, and the three-phase interfaces of the motors in the two electric drive units are both located in the first hollow hole. A high-voltage connector wire is connected to the bottom of the controller, and the high-voltage connector wire passes through the first hollow hole and is connected to the three-phase interfaces of the motors in the two electric drive units.

10. The centrally integrated coaxial distributed dual-motor electric drive axle according to claim 9 is characterized in that: A second hollow hole is further provided on the outer periphery of the intermediate shell, and the motors in the two electric drive units are both connected to a heat dissipation mechanism, which is exposed to the outside of the intermediate shell through the second hollow hole.

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