Coaxial electric drive axle

Abstract

A coaxial electric drive axle comprises an electric drive assembly and an electric drive axle housing, the drive assembly comprises a housing, a motor, a speed reducer gear set and a differential mechanism, the motor, the speed reducer gear set and the differential mechanism are arranged in the electric drive axle housing of an integrated structure, the electric drive axle housing comprises a main axle housing and a rear cover, the main axle housing is provided with a mounting cavity, the rear side of the main axle housing is connected with the rear cover, and the front side of the main axle housing is connected with the housing. The shell is provided with a stator fixing plate, a motor stator is fixed on the stator fixing plate, a motor shaft, an intermediate shaft and a differential mechanism are supported on the shell through bearings, the motor shaft is connected with the differential mechanism through a speed reducer gear set, the shell is connected with a main axle housing, and the motor, a primary driving gear, a secondary driven gear and the differential mechanism are arranged in a main axle housing mounting cavity. The motor shaft is a hollow shaft, one end of the left-end half shaft penetrates through the motor shaft to be connected with a differential mechanism left half shaft bevel gear, and one end of the right-end half shaft is connected with a differential mechanism right half shaft bevel gear.

Description

Technical Field

[0001] The utility model relates to the field of new energy vehicles, and particularly relates to a coaxial electric drive axle. Background Art

[0002] At present, the electric drive axles of new energy vehicles can be divided into parallel-axis electric drive axles and coaxial electric drive axles. The motor shaft of the parallel-axis electric drive axle is parallel to the half shaft, but the motor shaft and the half shaft are not on the same axis; the motor shaft of the coaxial electric drive axle is a hollow shaft, and the half shaft passes through the motor rotor and the motor shaft of the motor shaft, so that the motor shaft and the half shaft are on the same axis; the coaxial electric drive axle has the advantages of small vibration, compact structure and low mass compared with the parallel-axis electric drive axle.

[0003] In the prior art, such as the invention patent "A Semi-Coaxial Electric Drive Axle Assembly" with the application publication number of CN110469645A, in order to facilitate the installation of components such as motors and differentials, the coaxial electric drive axle is axially divided into multiple sections of shells along the motor shaft, such as a motor end cover, a motor mounting housing, a differential mounting housing, etc. The motor is installed in the motor mounting housing, and the differential is installed in the differential mounting housing. The multiple sections of shells are fixedly connected by bolts. The motor end cover and the differential mounting housing are respectively fixedly connected to the left axle tube and the right axle tube by bolts. However, since the axle tubes of the coaxial electric drive axle need to bear the torque of the electric drive axle, when the left and right axle tubes of this axially distributed coaxial electric drive axle bear a large torque, the positions of the bearings installed in the motor mounting housing and the differential mounting housing are prone to deformation, resulting in bearing damage, thereby damaging components such as the motor and the differential in the shell, seriously affecting the service life of the coaxial electric drive axle. Moreover, when components such as the motor and the differential are damaged and malfunction, the entire coaxial electric drive axle must be completely removed to replace and repair the damaged components, and the after-sales maintenance cost is extremely high. Summary of the Invention

[0004] In view of the above problems, the utility model provides a coaxial electric drive axle, which greatly enhances the load-bearing capacity of the electric drive axle by integrally forming the electric drive axle housing with the left and right axle tubes. At the same time, the electric drive assembly is separated from the electric drive axle housing, reducing the after-sales maintenance cost.

[0005] The technical solution of the present utility model is a coaxial electric drive axle, which includes an electric drive assembly and an electric drive axle housing. The drive assembly includes a housing, a motor, a reducer gear set, and a differential. The motor, the reducer gear set, and the differential are arranged in an integral electric drive axle housing. The electric drive axle housing includes a main axle housing and a rear cover. The main axle housing is provided with an installation cavity that penetrates through the front and rear. The rear side of the main axle housing is fixedly connected to the rear cover, and the front side of the main axle housing is fixedly connected to the housing of the drive assembly. The housing is provided with a stator fixing plate, and the stator of the motor is fixed on the stator fixing plate. The motor shaft, the intermediate shaft of the reducer gear set, and the differential are respectively supported by bearings in the housing. The motor shaft is connected to the differential through the reducer gear set. The housing is fixedly connected to the main axle housing by bolts, so that the motor, the first-stage driving gear, the second-stage driven gear, and the differential of the reducer gear set are located in the installation cavity of the main axle housing, and their central axes are all on the same straight line. The motor shaft is a hollow shaft, and one end of the left half shaft passes through the motor shaft to connect the left half shaft bevel gear of the differential, and one end of the right half shaft is connected to the right half shaft bevel gear of the differential.

[0006] Preferably, the reducer gear set further includes a first-stage driven gear and a second-stage driving gear. The first-stage driving gear is fixedly connected to the motor shaft, the first-stage driven gear and the second-stage driving gear are fixedly connected to the intermediate shaft of the reducer gear set, and the second-stage driven gear is fixedly connected to the differential housing. The first-stage driving gear meshes with the first-stage driven gear, and the second-stage driving gear meshes with the second-stage driven gear.

[0007] Further, the second-stage driving gear and the intermediate shaft are of an integrally formed structure.

[0008] Preferably, the stator fixing plate is fixedly connected to a bearing installation sleeve. The bearing installation sleeve is provided with a differential left bearing and the first-stage driving gear of the reducer gear set. The differential left bearing is used to support the left side of the differential.

[0009] Further, the bearing installation sleeve is provided with a meshing port, and the first-stage driving gear meshes with the first-stage driven gear of the reducer gear set through the meshing port.

[0010] Preferably, the housing includes a main housing, a reduction gear cover, and a motor rear cover. The reduction gear cover and the motor rear cover are both fixed to the main housing by bolts. A bearing groove is provided at the connection between the reduction gear cover and the main housing, and a bearing is arranged in the bearing groove to support the intermediate shaft of the reducer gear set. An electric motor left bearing seat is integrally formed on the motor rear cover, and the electric motor left bearing seat supports the left side of the motor shaft through an electric motor left bearing. A stator fixing plate is provided on the main housing, and an electric motor right bearing is fixed on the stator fixing plate to support the right side of the motor shaft. A differential right bearing seat is also provided on the main housing, and the differential right bearing seat supports the right side of the differential through a differential right bearing.

[0011] Furthermore, the right differential bearing housing includes a base and a bearing cover. The base is integrally formed with the main housing, and the bearing cover is fixedly connected to the base by bolts.

[0012] Preferably, the stator of the motor is provided with fixed through holes, and the stator fixing plate is provided with threaded holes corresponding to the fixed through holes of the stator. The stator is fixed to the stator fixing plate by long bolts.

[0013] Preferably, a plurality of mounting and fixing holes are evenly distributed on the housing. The housing is fixed to the main axle housing by bolts, so that the center lines of the main axle housing and the drive assembly coincide to form a sealed space.

[0014] Preferably, the motor further includes a rotor. The rotor is arranged inside the stator, and the rotor shaft of the rotor is the motor shaft.

[0015] The advantages of the present utility model are as follows: By integrally forming the electric drive axle housing with the left and right axle tubes, the load-bearing capacity of the coaxial electric drive axle is greatly improved. At the same time, by radially arranging the housing and the rear cover, the problem that the bearing position in the housing is prone to force deformation when the axle tube bears a large torque is avoided, ensuring the normal operation of the bearing and greatly improving the service life of the coaxial electric drive axle. Moreover, the electric drive assembly is separated from the electric drive axle housing of the present utility model. When the components inside the electric drive assembly are damaged and need to be repaired and replaced, only the electric drive assembly needs to be removed, and the damaged components are replaced, avoiding the problem of having to remove the entire electric drive axle from the vehicle body to replace the damaged components, greatly reducing the after-sales and maintenance costs of new energy vehicles using the coaxial electric drive axle of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the electric drive assembly and the electric drive axle housing of the present utility model;

[0017] Figure 2 is a schematic sectional view of the electric drive assembly of the present utility model;

[0018] Figure 3 is a schematic structural diagram of the electric drive assembly of the present utility model;

[0019] Figure 4 is a schematic structural diagram of the housing of the electric drive assembly of the present utility model;

[0020] Figure 5 is a schematic structural diagram of the motor of the present utility model;

[0021] Figure 6 is a schematic sectional view of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] See Figures 1 to 6, a coaxial electric drive axle, comprising an electric drive assembly 1 and an electric drive axle housing 2. The drive assembly 1 includes a housing 11, a motor 12, a reducer gear set 13, and a differential 14. The motor 12, the reducer gear set 13, and the differential 14 are arranged in an integral electric drive axle housing 2. The electric drive axle housing 2 includes a main axle housing 21 and a rear cover 22. The main axle housing 21 is provided with an installation cavity that penetrates through the front and rear. The rear side of the main axle housing 21 is fixedly connected to the rear cover 22, and the front side of the main axle housing 21 is fixedly connected to the housing 11 of the drive assembly 1. The housing 11 is provided with a stator fixing plate 114. The stator 121 of the motor 12 is provided with fixing through holes, and the stator fixing plate 114 is provided with threaded holes corresponding to the fixing through holes of the stator 121. The stator 121 is fixed to the stator fixing plate 114 by long bolts. The stator fixing plate 114 is fixedly connected to a bearing installation sleeve 15. A differential left bearing 342 and a first-stage driving gear 131 of the reducer gear set 13 are arranged inside the bearing installation sleeve 15. The differential left bearing 342 is used to support the left side of the differential. The bearing installation sleeve 15 is provided with a meshing port, and the first-stage driving gear 131 meshes with the first-stage driven gear of the reducer gear set 13 through the meshing port. The motor 12 further includes a rotor 122. The rotor 122 is arranged inside the stator 121, and the rotor shaft of the rotor 122 is the motor shaft 1221. The housing 11 includes a main housing 111, a reduction gear cover 112, and a motor rear cover 113. The reduction gear cover 112 and the motor rear cover 113 are both fixed to the main housing 111 by bolts. A bearing groove is provided at the connection between the reduction gear cover 112 and the main housing 111, and a bearing is arranged in the bearing groove to support the intermediate shaft of the reducer gear set 13. An integral motor left bearing seat is formed on the motor rear cover 113. The motor left bearing seat supports the left side of the motor shaft 1221 through a motor left bearing 321. A stator fixing plate 114 is provided on the main housing 111, and a motor right bearing 322 is fixed on the stator fixing plate 114 to support the right side of the motor shaft 1221. A differential right bearing seat is further provided on the main housing 111. The differential right bearing seat includes a base and a bearing cover 115. The base is integrally formed with the main housing 111, and the bearing cover 115 is connected and fixed to the base by bolts. The differential right bearing seat supports the right side of the differential through a differential right bearing 341. The reducer gear set 13 further includes a first-stage driven gear 132, a second-stage driving gear 133. The first-stage driving gear 131 is fixedly connected to the motor shaft. The first-stage driven gear 132 and the second-stage driving gear 133 are fixedly connected to the intermediate shaft of the reducer gear set 13. The second-stage driving gear 133 and the intermediate shaft are of an integral formed structure. A second-stage driven gear 134 is fixedly connected to the housing of the differential 14. The first-stage driving gear 131 meshes with the first-stage driven gear 132, and the second-stage driving gear 133 meshes with the second-stage driven gear 134.A plurality of mounting and fixing holes are evenly distributed on the housing 11. The housing 11 is fixed to the main axle housing 21 by bolts, so that the center lines of the main axle housing 21 and the drive assembly 1 coincide to form a sealed space. At the same time, the motor 12, the first-stage driving gear 131 of the reducer gear set 13, the second-stage driven gear 134, and the differential 14 are located in the installation cavity of the main axle housing 21, and their central axes are all on the same straight line. The motor shaft 1221 is a hollow shaft. One end of the left half shaft 41 passes through the motor shaft and is connected to the left half shaft bevel gear of the differential 14, and one end of the right half shaft 42 is connected to the right half shaft bevel gear of the differential 14.

[0023] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications made by those skilled in the art without departing from the spirit of the present invention fall within the protection scope of the present invention.

Claims

1. A coaxial electric drive axle, comprising a drive assembly (1) and an electric drive axle housing (2), wherein the drive assembly (1) includes a housing (11), a motor (12), a reduction gear set (13), and a differential (14), and is characterized in that: The motor (12), the reduction gear set (13), and the differential (14) are arranged in an integral electric drive axle housing (2). The electric drive axle housing (2) includes a main axle housing (21) and a rear cover (22). The main axle housing (21) is provided with an installation cavity that penetrates through the front and rear. The rear side of the main axle housing (21) is fixedly connected to the rear cover (22). The front side of the main axle housing (21) is fixedly connected to the housing (11) of the drive assembly (1). The housing (11) is provided with a stator fixing plate (114). The stator (121) of the motor (12) is fixed on the stator fixing plate (114). The motor shaft (1221) of the motor (12), the intermediate shaft of the reduction gear set (13), and the differential (14) are respectively supported by bearings in the housing (11). The motor shaft (1221) is connected to the differential (14) through the reduction gear set (13). The housing (11) is fixedly connected to the main axle housing (21) by bolts, so that the motor (12), the first-stage driving gear (131) of the reduction gear set (13), the second-stage driven gear (134), and the differential (14) are located in the installation cavity of the main axle housing (21), and their central axes are all on the same straight line. The motor shaft (1221) is a hollow shaft. One end of the left half shaft (41) passes through the motor shaft and is connected to the left half shaft bevel gear of the differential (14). One end of the right half shaft (42) is connected to the right half shaft bevel gear of the differential (14).

2. The coaxial electric drive axle according to claim 1, characterized in that: The reduction gear set (13) further includes a first-stage driven gear (132) and a second-stage driving gear (133). The first-stage driving gear (131) is fixedly connected to the motor shaft. The first-stage driven gear (132) and the second-stage driving gear (133) are fixedly connected to the intermediate shaft of the reduction gear set (13). The second-stage driven gear (134) is fixedly connected to the housing of the differential (14). The first-stage driving gear (131) meshes with the first-stage driven gear (132), and the second-stage driving gear (133) meshes with the second-stage driven gear (134).

3. The coaxial electric drive axle according to claim 2, wherein: The second-stage driving gear (133) and the intermediate shaft are of an integrally formed structure.

4. The coaxial electric drive axle according to claim 1, characterized in that: The stator fixing plate (114) is fixedly connected to a bearing installation sleeve (15). The differential left bearing (342) and the first-stage driving gear (131) of the reduction gear set (13) are arranged in the bearing installation sleeve (15). The differential left bearing (342) is used to support the left side of the differential.

5. The coaxial electric drive axle according to claim 4, wherein: The bearing installation sleeve (15) is provided with a meshing opening. The first-stage driving gear (131) meshes with the first-stage driven gear of the reduction gear set (13) through the meshing opening.

6. The coaxial electric drive axle according to claim 1, characterized in that: The housing (11) includes a main housing (111), a reduction gear cover (112), and a motor rear cover (113). The reduction gear cover (112) and the motor rear cover (113) are both fixed to the main housing (111) by bolts. A bearing groove is provided at the connection between the reduction gear cover (112) and the main housing (111), and a bearing is arranged in the bearing groove to support the intermediate shaft of the reduction gear set (13). An integral motor left bearing seat is provided on the motor rear cover (113), and the motor left bearing seat supports the left side of the motor shaft (1221) through a motor left bearing (321). A stator fixing plate (114) is provided on the main housing (111), and a motor right bearing (322) is fixed on the stator fixing plate (114) to support the right side of the motor shaft (1221). A differential right bearing seat is further provided on the main housing (111), and the differential right bearing seat supports the right side of the differential through a differential right bearing (341).

7. A coaxial electric drive axle according to claim 6, characterized in that: The differential right bearing seat includes a base and a bearing cover (115). The base is integrally formed with the main housing (111), and the bearing cover (115) is connected and fixed to the base by bolts.

8. The coaxial electric drive axle according to claim 1, wherein: Fixed through-holes are provided on the stator (121) of the motor (12), and threaded holes corresponding to the fixed through-holes of the stator (121) are provided on the stator fixing plate (114). The stator (121) is fixed to the stator fixing plate (114) by long bolts.

9. The coaxial electric drive axle according to claim 1, characterized in that: A plurality of mounting and fixing holes are evenly distributed on the housing (11), and the housing (11) is fixed to the main axle housing (21) by bolts, so that the center line of the main axle housing (21) coincides with that of the drive assembly (1) to form a sealed space.

10. The coaxial electric drive axle according to claim 1, characterized in that: The motor (12) further includes a rotor (122). The rotor (122) is arranged inside the stator (121), and the rotor shaft of the rotor (122) is the motor shaft (1221).

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