JP2021160601A - Vehicle electric driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electric drive device for a vehicle in which the tooth surface of a hypoid gear is easily lubricated and the motor is easily cooled.
An electric drive device for a vehicle is provided by a motor having a housing, a stator housed in the housing, a rotor housed in the housing, a first transmission mechanism housed in the housing, and a hypoid pinion. It includes a pinion gear that is configured and rotates integrally with the output shaft of the first transmission mechanism, and a differential gear that is configured by a hypoid gear and has a ring gear that meshes with the pinion gear and is housed in a housing. The housing contains a first storage chamber containing the stator and rotor and containing the first oil, and a second storage chamber containing the pinion gear and the differential gear and containing a second oil having a viscosity higher than that of the first oil. There is a room and.
[Selection diagram] Fig. 2

Description

The present invention relates to an electric drive device for a vehicle.

Conventionally, an electric drive device for a vehicle including a motor, a gear mechanism for decelerating, a differential gear, a drive shaft, and an axle case is known.

EP3501867A1

In this type of electric drive device for vehicles, a hypoid gear is used to transmit power from the gear mechanism to the differential gear. Therefore, it is beneficial to obtain a configuration in which the tooth surface of the hypoid gear is easily lubricated and the motor is easily cooled. ..

Therefore, one of the problems of the present invention is, for example, to obtain an electric drive device for a vehicle in which the tooth surface of the hypoid gear is easily lubricated and the motor is easily cooled.

The vehicle electric drive device of the present invention includes, for example, a motor having a housing, a stator housed in the housing, and a rotor housed in the housing, and an input shaft to which power is transmitted from the motor. A first gear having an output shaft arranged at a distance from the input shaft and a plurality of gears interposed between the input shaft and the output shaft to transmit the power, and housed in the housing. A differential gear having a transmission mechanism, a pinion gear composed of a hypoid pinion and rotating integrally with the output shaft, and a ring gear composed of a hypoid gear and meshing with the pinion gear, and a differential gear housed in the housing and described in the housing. A drive shaft for transmitting the power from the differential gear is provided, and the housing houses the stator and the rotor, a first storage chamber containing the first oil, and the pinion gear and the differential gear. A second storage chamber containing a second oil having a gear viscosity higher than that of the first oil is provided.

According to the embodiment of the present invention, it is possible to obtain an electric drive device for a vehicle in which the tooth surface of the hypoid gear is easily lubricated and the motor is easily cooled.

FIG. 1 is an exemplary plan view of the vehicle electric drive device of the embodiment. FIG. 2 is an exemplary cross-sectional view of the vehicle electric drive device of the embodiment. FIG. 3 is an exemplary front view of a part of the vehicle electric drive device of the first modification of the embodiment.

Hereinafter, exemplary embodiments of the present invention will be disclosed. In this specification, the ordinal number is used to distinguish parts, parts, etc., and does not indicate the order or priority.

FIG. 1 is an exemplary plan view of the vehicle electric drive device 1 of the present embodiment. The vehicle electric drive device 1 is provided in the vehicle and rotationally drives the wheels 18L and 18R of the vehicle. In the following description, for convenience, three directions orthogonal to each other are defined. The X direction is the same as the front in the vehicle front-rear direction, the Y direction is along the vehicle width direction (vehicle width direction), and the Z direction is the same as above in the vehicle vertical direction. The vehicle electric drive device 1 is also referred to as an electric axle device.

FIG. 2 is an exemplary cross-sectional view of the vehicle electric drive device 1 of the embodiment. As shown in FIG. 2, the vehicle electric drive device 1 includes an axle case 10, a motor 11, a connection mechanism 12, a transmission 13, a differential gear 14, drive shafts 15L, 15R, and a parking lock gear. 17 and a parking brake (not shown) are provided. In the vehicle electric drive device 1, the power output from the motor 11 is transmitted to the drive shafts 15L and 15R via the connection mechanism 12, the transmission 13, and the differential gear 14. As a result, the wheels 18L and 18R fixed to the drive shafts 15L and 15R rotate. The axle case 10 is also referred to as a banjo.

Further, as shown in FIGS. 1 and 2, the vehicle electric drive device 1 includes a drive unit 100 and a transmission unit 200.

As shown in FIG. 2, the drive unit 100 includes a motor 11, a connection mechanism 12, and a drive housing 101.

The drive unit 100 is detachably attached to the axle case 10 in a state of being located on the X direction side, that is, the front side of the axle case 10. The drive unit 100 extends from the axle case 10 in the X direction, that is, forward. In other words, the drive unit 100 projects in the X direction from the axle case 10.

The transmission unit 200 includes a transmission 13, a differential gear 14, a parking lock gear 17, a parking brake, and a transmission housing 201. The transmission unit 200 is detachably attached to the axle case 10 in a state of being located on the opposite side of the axle case 10 in the X direction, that is, on the rear side.

The transmission unit 200 extends from the axle case 10 in the opposite direction to the X direction, that is, rearward. In other words, the transmission unit 200 projects from the axle case 10 in the opposite direction to the X direction.

The drive unit 100 and the transmission unit 200 are attached to the axle case 10 independently of each other. In other words, the drive unit 100 and the transmission unit 200 are separately attached to the axle case 10. That is, the motor 11 and the transmission 13 are attached to the axle case 10 independently of each other. Further, as shown in FIGS. 1 and 2, the drive unit 100 and the transmission unit 200 are aligned with the leaf springs 1005L and 1005R in the Y direction, that is, in the vehicle width direction. Further, the drive unit 100 and the transmission unit 200 have substantially the same width in the vehicle width direction. The drive unit 100 and the transmission unit 200 may have different widths in the vehicle width direction.

The axle case 10 is a rigid axle case and houses the differential gear 14 and the drive shafts 15L and 15R. The axle case 10, the drive housing 101, and the transmission housing 201 constitute the housing 2 of the vehicle electric drive device 1.

The axle case 10 is composed of a combination of a plurality of members. Specifically, the axle case 10 has a base member 91 and two tubular members 93R and 93L. The base member 91 is formed in a frame shape (endless shape), and is provided with a storage chamber for accommodating the differential gear 14 inside. Further, the two tubular members 93R and 93L extend from the base member 91 in opposite directions along the vehicle width direction. Specifically, the tubular member 93R extends from the base member 91 in the Y direction, and the tubular member 93L extends from the base member 91 in the opposite direction in the Y direction. The two tubular members 93R and 93L are fixed to the base member 91 by a binder such as a screw or a bolt, welding, or the like. Each of the two tubular members 93R and 93L is provided with a storage chamber for accommodating the drive shafts 15L and 15R. The means for fixing the members of the axle case 10 is not limited to the above. The axle case 10 is also referred to as a case or a rigid axle.

Further, the base member 91 has two mating surfaces 91a and 91b. The mating surface 91a is the X direction, that is, the front end surface, and faces the X direction. The mating surface 91b is the opposite direction in the X direction, that is, the rear end surface, and faces the opposite direction in the X direction. The mating surfaces 91a and 91b are flat surfaces.

The drive shafts 15L and 15R extend in the Y direction, that is, in the vehicle width direction. The drive shafts 15L and 15R are arranged in a straight line with an interval in the Y direction (vehicle width direction). The differential gear 14 is arranged between the drive shafts 15L and 15R. The drive shafts 15L and 15R are housed in the axle case 10 and are supported by the axle case 10 via bearings so as to be rotatable around the central axis Ax1. The central axis Ax1 is along the Y direction, that is, the vehicle width direction.

The drive housing 101 of the drive unit 100 includes a base member 102 and a motor case 11a. The base member 102 has a mating surface 102a. The mating surface 102a is the opposite direction in the X direction, that is, the rear end surface, and faces the opposite direction in the X direction. The mating surface 102a is overlapped with the mating surface 91a of the axle case 10. The base member 102 is fixed to the base member 91 by a binder such as a screw or a bolt in a state of being overlapped with the base member 91 on the X direction side, that is, the front side of the base member 91 of the axle case 10. The base member 102 is provided with a part of the accommodating chamber for accommodating the connection mechanism 12 and a part of the accommodating chamber for accommodating the differential gear 14 and the like. The motor case 11a is fixed to the base member 102 by a binder such as a screw or a bolt in a state of being overlapped with the base member 102 on the X direction side, that is, the front side of the base member 102. A storage chamber for accommodating the connection mechanism 12 is provided between the base member 102 and the cover member 11f.

The motor 11 includes a motor case 11a, a motor shaft 11b, a rotor 11c, and a stator 11d.

The motor case 11a houses a part of the motor shaft 11b, the rotor 11c, and the stator 11d. The motor case 11a has a concave main body 11e and a cover member 11f that covers the opening of the main body 11e. The cover member 11f is provided with an opening 11g that penetrates the cover member 11f. That is, the opening 11g is a through hole. The cover member 11f is fixed to the main body 11e. The cover member 11f is removable from the main body 11e.

The motor case 11a is supported (fixed) to the axle case 10. Specifically, the motor case 11a is supported (fixed) to the axle case 10 via the base member 102. The motor case 11a is detachably attached to the base member 102 with screws or the like. That is, the motor 11 is detachably attached to the axle case 10.

The motor shaft 11b extends in the X direction, that is, in the front-rear direction of the vehicle, and is rotatably supported by the motor case 11a around the central axis Ax2. The central axis Ax2 is along the X direction (vehicle front-rear direction), that is, a direction orthogonal to (intersecting) the central axis Ax1. A part of the motor shaft 11b projects from the opening 11g to the outside of the motor case 11a. Further, the portion of the motor shaft 11b inside the main body 11e is rotatably supported by two bearings B12 and B13. The two bearings B12 and B13 are arranged so as to be spaced apart from each other in the X direction. The bearing B12 is supported by the main body 11e. The bearing B13 is supported by the cover member 11f. Specifically, the bearing B13 is fitted in the opening 11g provided in the cover member 11f. Further, the portion of the motor shaft 11b protruding from the main body 11e is rotatably supported by two bearings B1 and B2. The two bearings B1 and B2 are arranged so as to be spaced apart from each other in the X direction. The two bearings B1 and B2 are supported by the cover member 11f and the base member 102. That is, the portion of the motor shaft 11b protruding from the main body 11e is rotatably supported by the cover member 11f and the base member 102 via the two bearings B1 and B2.

The rotor 11c rotates integrally with the motor shaft 11b. The stator 11d surrounds the outer circumference of the rotor 11c and is fixed to the motor case 11a.

The motor 11 applies torque (power) around the central axis Ax2 to the motor shaft 11b by being supplied with electric power. That is, the motor shaft 11b outputs power. The power output from the motor shaft 11b of the motor 11 is input to the transmission 13 via the connection mechanism 12.

The connection mechanism 12 has a first gear 71, a second gear 72, and a transmission shaft 73. The connection mechanism 12 is a reduction mechanism that decelerates the rotation input to the first gear 71 and outputs the rotation from the second gear 72. The connection mechanism 12 may be, for example, a speed-increasing mechanism that accelerates the rotation input to the first gear 71 and outputs it from the second gear 72, or a mechanism that neither decelerates nor accelerates. May be good. The connection mechanism 12 is also referred to as a coupling mechanism or a power transmission mechanism. The connection mechanism 12 is an example of the second transmission mechanism.

The transmission shaft 73 is arranged apart from and parallel to the motor shaft 11b of the motor 11. The transmission shaft 73 extends in the X direction, that is, in the front-rear direction of the vehicle, and is rotatably supported by the drive housing 101 around the central axis Ax3. The central axis Ax3 is parallel to the central axis Ax2 and is aligned with the central axis Ax2 at intervals. Specifically, the transmission shaft 73 is rotatably supported by two bearings B3 and B4. The two bearings B3 and B4 are arranged at intervals in the X direction. The two bearings B3 and B4 are supported by the cover member 11f and the base member 102. That is, the transmission shaft 73 is rotatably supported by the cover member 11f and the base member 102 via two bearings B3 and B4.

The first gear 71 is fixed to the motor shaft 11b of the motor 11 and rotates integrally with the motor shaft 11b around the central axis Ax2.

The second gear 72 is fixed to the transmission shaft 73 and rotates integrally with the transmission shaft 73 around the central axis Ax3.

The transmission housing 201 of the transmission unit 200 includes a differential housing 202 and a transmission housing 24 described later. The transmission housing 24 is also referred to as a transmission case.

The differential housing 202 has two mating surfaces 202a, 202b. The mating surface 202a is the X direction, that is, the front end surface, and faces the X direction. The mating surface 202a is overlapped with the mating surface 91b of the axle case 10. The mating surface 202b is the opposite direction in the X direction, that is, the rear end surface, and faces the opposite direction in the X direction. The mating surface 202b is included in the partition wall 202c of the differential housing 202. The mating surfaces 202a and 202b are flat surfaces.

The differential housing 202 is fixed to the base member 91 by a binder such as a screw or a bolt in a state of being overlapped with the base member 91 on the side opposite to the X direction of the base member 91 of the axle case 10, that is, on the rear side. The differential housing 202 is provided with a part of a storage chamber for accommodating the differential gear 14 and the like.

The transmission 13 is arranged on the opposite side of the motor 11 with respect to the central axis Ax1 of the rotation of the ring gear 52 and the drive shafts 15L and 15R. That is, the central axis Ax1 is located between the motor 11 and the transmission 13. More specifically, the motor 11 and the transmission 13 are arranged in the front-rear direction of the vehicle with the central axis Ax1 in between. Further, the motor 11 and the transmission 13 are located on opposite sides of the axle case 10.

The transmission 13 includes an input shaft 21, an output shaft 22, a plurality of gear stages 30, a gear connection mechanism 23, and a transmission housing 24. The input shaft 21, the output shaft 22, the plurality of gear stages 30, and the gear connecting mechanism 23 are housed in the transmission housing 24. As an example, the transmission 13 has a configuration in which the rotation (power) input to the input shaft 21 is decelerated and the rotation (power) input to the input shaft 21 is accelerated. The transmission 13 may have a configuration in which only deceleration is performed or a configuration in which only speed increase is performed. That is, the transmission 13 may be configured to perform at least one of deceleration and acceleration. The transmission 13 is an example of the first transmission mechanism.

The transmission housing 24 has a mating surface 24a. The mating surface 24a is the X direction, that is, the front end surface, and faces the X direction. The mating surface 24a is overlapped with the mating surface 202b of the differential housing 202.

The transmission housing 24 is supported (fixed) to the axle case 10. Specifically, the transmission housing 24 is supported (fixed) to the axle case 10 via the differential housing 202. The transmission housing 24 is detachably attached to the differential housing 202 by screws or the like. That is, the transmission 13 is detachably attached to the axle case 10.

The input shaft 21 and the output shaft 22 extend in the X direction, that is, in the front-rear direction of the vehicle, are separated from each other, and are arranged in parallel. The input shaft 21 is supported by the transmission housing 24 so as to be rotatable around the central axis Ax3. The central axis Ax3 is along a direction orthogonal to (intersecting) the central axis Ax1. Specifically, the input shaft 21 is rotatably supported by two bearings B5 and B6. The two bearings B5 and B6 are arranged at intervals in the X direction. The bearing B5 is located in the X direction of B6. The two bearings B5 and B6 are supported by the transmission housing 201. That is, the input shaft 21 is rotatably supported by the transmission housing 201 via two bearings B5 and B6. More specifically, the bearing B5 is fitted in the opening 202d provided in the partition wall 202c of the differential housing 202 and supported by the differential housing 202. The bearing B6 is supported by the transmission housing 24. The input shaft 21 is inserted into the opening 202d and penetrates the opening 202d.

The output shaft 22 is supported by the transmission housing 24 so as to be rotatable around the central axis Ax4. The central axis Ax4 is along a direction orthogonal to (intersecting) the central axis Ax1. The central axis Ax4 is parallel to the central axis Ax3 and is aligned with the central axis Ax3 at intervals. Specifically, the output shaft 22 is rotatably supported by two bearings B7 and B8. The two bearings B7 and B8 are arranged at intervals in the X direction. The bearing B7 is located in the X direction of B8. The bearing B7 is the one of the two bearings B7 and B8 that is closer to the differential gear 14. The two bearings B7 and B8 are supported by the transmission housing 201. That is, the input shaft 21 is rotatably supported by the transmission housing 201 via two bearings B7 and B8. More specifically, the bearing B7 is fitted in the opening 202e provided in the partition wall 202c of the differential housing 202 and supported by the differential housing 202. Further, the bearing B7 is composed of a combination of two bearings B7a and B7b. The bearing B8 is supported by the transmission housing 24. The output shaft 22 is inserted into the opening 202e and penetrates the opening 202e. Here, the opening 202d and the opening 202e are separated from each other. Further, the opening 202d and the opening 202e and the opening 11g are separated from each other. The central axes Ax1 to Ax4 are also referred to as rotation axes.

The power of the motor 11 is input to the input shaft 21 via the connection mechanism 12, and the motor 11 is rotated by the power.

Each of the plurality of gear stages 30 is a constantly meshing type gear stage, and is provided over the input shaft 21 and the output shaft 22. The plurality of gear stages 30 have different gear ratios (gear ratio = rotation speed of input shaft 21 / rotation speed of output shaft 22). Gear stages are also referred to as gear pairs. The gear ratio is also called the gear ratio.

The plurality of gear stages 30 include a first speed gear stage 31 and a second speed gear stage 32. The first speed gear stage 31 and the second speed gear stage 32 are arranged so as to be spaced apart from each other in the axial direction of the central axis Ax2 of the input shaft 21. The gear ratio of the second speed gear stage 32 is relatively smaller than the gear ratio of the first speed gear stage 31. The first speed gear stage 31 constitutes the reduction mechanism 41 by the input shaft 21 and the output shaft 22. The speed reduction mechanism 41 decelerates the rotation input to the input shaft 21 and outputs the rotation from the output shaft 22. The second speed gear stage 32 constitutes the reduction mechanism 42 by the input shaft 21 and the output shaft 22. The speed reduction mechanism 42 accelerates the rotation input to the input shaft 21 and outputs the rotation from the output shaft 22. Further, the speed reduction mechanism 41 and the speed reduction mechanism 42 are supported by the axle case 10 via the transmission housing 24 and the differential housing 202. The first speed gear stage 31 is also referred to as a low gear, and the second speed gear stage 32 is also referred to as a high gear. The configuration of the plurality of gear stages 30 is not limited to the above. For example, one of the first speed gear stage 31 and the second speed gear stage 32 may be a speed increasing structure, and both the first speed gear stage 31 and the second speed gear stage 32 are speed increasing mechanisms. There may be.

The first speed gear stage 31 has a drive gear 33 and a driven gear 34 that mesh with each other, and the second speed gear stage 32 has a drive gear 35 and a driven gear 36 that mesh with each other. The drive gears 33 and 35 and the driven gears 34 and 36 are examples of gears.

The drive gears 33 and 35 are fixed to the input shaft 21 and rotate integrally with the input shaft 21 around the central axis Ax3.

The driven gears 34 and 36 are supported by the output shaft 22 via bearings so as to be rotatable relative to the output shaft 22, and rotate around the central axis Ax4. The driven gears 34 and 36 can idle with respect to the output shaft 22 when they are not connected to the output shaft 22 by the gear connecting mechanism 23. Further, the driven gears 34 and 36 are restricted from moving in the axial direction of the central axis Ax4.

Further, the output shaft 22 is provided with a final gear 38. The final gear 38 is fixed to the output shaft 22 and rotates integrally with the output shaft 22 around the central axis Ax4. The final gear 38 is composed of a hypoid pinion. The final gear 38 is an example of a pinion gear.

The gear connection mechanism 23 is provided between the driven gear 34 of the first speed gear stage 31 and the driven gear 36 of the second speed gear stage 32. The gear connection mechanism 23 selects a connection state (coupled state) and a cutoff state (non-coupling state) between the output shaft 22 and the driven gear 34 of the first speed gear stage 31 and the driven gear 36 of the second speed gear stage 32. Switch to. That is, the gear connection mechanism 23 switches the transmission state of rotation between the output shaft 22 and the driven gears 34 and 36. The gear connection mechanism 23 is also referred to as a switching mechanism or a selection mechanism.

The gear connection mechanism 23 has a hub 43 and a sleeve 44. The hub 43 is coupled to the output shaft 22 and rotates integrally with the output shaft 22 around the central axis Ax4. The sleeve 44 is coupled to the hub 43 by spline coupling, rotates integrally with the hub 43 around the central axis Ax4, and is movable with respect to the hub 43 in the axial direction of the output shaft 22. That is, the sleeve 44 rotates integrally with the output shaft 22 around the central axis Ax4, and can move in the axial direction of the output shaft 22 with respect to the output shaft 22.

The sleeve 44 has a first coupling position to be coupled to the driven gear 34, a second coupling position to be coupled to the driven gear 36, and a neutral position between the first coupling position and the second coupling position (FIG. 2). It is configured to be movable between. An actuator and a moving mechanism (not shown) selectively position the sleeve 44 in one of a first coupling position with the driven gear 34, a second coupling position with the driven gear 36, and a neutral position. When the sleeve 44 is positioned at the first coupling position with the driven gear 34, the output shaft 22 and the driven gear 34 can rotate integrally. In this case, transmission of the first speed rotation from the motor shaft 11b of the motor 11 to the connection mechanism 12, the drive gear 33, the driven gear 34, the output shaft 22, the final gear 38, the differential gear 14, and the drive shafts 15L and 15R. The route is constructed.

Further, in the state where the sleeve 44 is positioned at the second coupling position with the driven gear 36, the output shaft 22 and the driven gear 36 can rotate integrally. In this case, the transmission of the second speed rotation from the motor shaft 11b of the motor 11 to the connection mechanism 12, the drive gear 35, the driven gear 36, the output shaft 22, the final gear 38, the differential gear 14, and the drive shafts 15L and 15R. The route is constructed.

When the sleeve 44 is positioned in the neutral position, the driven gears 34 and 36 can idle with respect to the output shaft 22.

The differential gear 14 includes a differential gear case 51, a ring gear 52, and a differential mechanism (not shown).

The differential gear case 51 is housed in the differential housing 202. The differential gear case 51 is supported by the differential housing 202 via bearings B9 and B10 so as to be rotatable around the central axis Ax1.

The ring gear 52 is composed of a hypoid gear. The ring gear 52 is fixed to the differential gear case 51 and rotates integrally with the differential gear case 51 around the central axis Ax1. That is, the ring gear 52 is rotatably supported by the differential housing 202 via the bearing B7 around the central axis Ax1. Further, the ring gear 52 meshes with the final gear 38, and power is transmitted from the final gear 38. The final gear 38 and the ring gear 52 form a reduction gear ratio (so-called final reduction ratio).

The differential mechanism is housed in the differential gear case 51. The differential mechanism has a pinion shaft, two pinion gears, and two side gears. The pinion shaft extends in a direction orthogonal to the central axis Ax1. The pinion shaft is supported by the differential gear case 51. The pinion gear is supported by the pinion shaft so as to be rotatable around the pinion shaft. The pinion shaft and the pinion gear rotate around the central axis Ax1 integrally with the differential gear case 51. The two side gears are engaged with the two pinion gears while being fixed to the ends of the two drive shafts 15L and 15R, respectively.

In the differential gear 14 having the above configuration, when the ring gear 52 rotates, the differential gear case 51 rotates integrally with the pinion shaft. The pinion shaft revolves the pinion gear around the central axis Ax1. As a result, the side gear rotates around the central axis Ax1, and the drive shafts 15L and 15R rotate. When a differential rotation occurs in the side gear, the pinion gear rotates around the pinion shaft to absorb the differential rotation.

The transmission unit 200 having the above configuration is composed of a combination of a plurality of units. Specifically, the transmission unit 200 has a differential unit 203 and a gear unit 204.

The differential unit 203 includes a differential gear 14 and a differential housing 202. The gear unit 204 has a transmission 13 (reduction mechanism 41, reduction mechanism 42, transmission housing 24). The gear unit 204 is detachably attached to the differential unit 203.

Further, the transmission shaft 73 and the input shaft 21 of the transmission 13 are arranged on the same straight line and are connected to each other by the coupling portion 80. The transmission shaft 73, the input shaft 21, and the coupling portion 80 form a through drive shaft 81 that extends in the X direction, that is, in the vehicle front-rear direction, and transmits power between the motor 11 and the transmission 13. The through drive shaft 81 is rotatable around the central axis Ax3, extends from the X direction side (front side) of the axle case 10 to the opposite side (rear side) of the X direction, and the power output from the motor shaft 11b is transmitted. Will be done. The through drive shaft 81 is housed in the axle case 10 and is supported by the axle case 10 via bearings B3 to B6 so as to be rotatable around the central axis Ax3. The through drive shaft 81 is also referred to as a coupling shaft. The transmission shaft 73 is also referred to as a first portion, and the input shaft 21 is also referred to as a second portion.

The through drive shaft 81 extends in the X direction, that is, in the vehicle front-rear direction, at a position separated from the drive shaft 15R (central axis Ax1), specifically, in the Z direction, that is, above the central axis Ax1. Therefore, in top view, the through drive shaft 81 overlaps (intersects) the central axis Ax1. The through drive shaft 81 may be provided above the drive shaft 15L and the differential gear 14, or may be provided below the drive shaft 15R, the drive shaft 15L, and the differential gear 14.

The coupling portion 80 separately couples the transmission shaft 73 and the input shaft 21. The coupling portion 80 is housed in the differential housing 202. The coupling portion 80 is located closer to the drive gear 33 among the second gear 72 of the connection mechanism 12 and the drive gear 33 of the reduction gear 41 in the transmission 13. In top view, the coupling portion 80 is located behind the drive shaft 15R. The position of the connecting portion 80 is not limited to the above.

The coupling portion 80 splines the transmission shaft 73 and the input shaft 21, for example. Specifically, the coupling portion 80 has a male spline portion 80a provided on the transmission shaft 73 and a female spline portion 80b provided on the input shaft 21 and spline-coupled with the male spline portion 80a. In such a configuration, the transmission shaft 73 and the input shaft 21 can be separated from each other by separating the transmission shaft 73 and the input shaft 21 along the axial direction of the central axis Ax3, and the transmission shaft 73 and the input shaft 21 can be separated from each other. The transmission shaft 73 and the input shaft 21 can be coupled by bringing the 21 into close proximity along the axial direction of the central axis Ax3. The input shaft 21 may be provided with a male spline portion 80a, and the transmission shaft 73 may be provided with a female spline portion 80b. Further, the coupling portion 80 may detachably connect the transmission shaft 73 and the input shaft 21 with a coupling tool such as a screw or a bolt.

Further, the drive unit 100 has a bearing B11 that rotatably supports the coupling portion 80. The bearing B11 supports the outer circumference of the female spline portion 80b provided on the input shaft 21. The bearing B11 is supported by the base member 102 of the drive housing 101. Specifically, the bearing B11 is provided in the partition wall 102c of the base member 102 and is fitted in the opening 102g. The opening 102 g is a through hole. The bearing B11 is a bearing different from the bearings B3 to B6. The diameter of the bearing B11 is smaller than the diameter of the bearings B3 to B6.

As described above, in the present embodiment, the drive unit 100 has a drive housing 101 that houses the motor 11 and the transmission shaft 73, and the coupling portion 80 is housed in the drive housing 101.

Further, the parking lock gear 17 and the parking brake are connected to the output shaft 22 of the transmission 13.

Further, in the present embodiment, the motor 11 and the transmission 13 (reduction mechanism 41, reduction mechanism 42) are arranged on opposite sides to each other with respect to the rotation central shafts Ax1 of the ring gear 52 and the drive shafts 15L and 15R. .. That is, the central axis Ax1 is located between the motor 11 and the transmission 13 (reduction mechanism 41, reduction mechanism 42). More specifically, the motor 11 and the transmission 13 (reduction mechanism 41, reduction mechanism 42) are arranged in the front-rear direction of the vehicle with the central axis Ax1 in between.

Next, the compartment in the housing 2 and the oil contained in the housing 2 will be described. As shown in FIG. 2, a plurality of storage chambers R1 to R4 are provided in the housing 2.
The accommodation chambers R1 to R4 are arranged in the front-rear direction of the vehicle. The accommodation chamber R2 is located on the vehicle rear side of the accommodation chamber R1, the accommodation chamber R3 is located on the vehicle rear side of the accommodation chamber R2, and the accommodation chamber R4 is located on the vehicle rear side of the accommodation chamber R3. The accommodation chamber R1 and the accommodation chamber R2 are separated by a cover member 11f of the differential housing 202. The accommodation chamber R2 and the accommodation chamber R3 are separated by a partition wall 102c of the differential housing 202. The accommodation chamber R3 and the accommodation chamber R4 are separated by a partition wall 202c of the differential housing 202.

The accommodation chamber R1 accommodates the stator 11d and the rotor 11c. Oil 501 is contained in the containment chamber R1. Line L1 in FIG. 2 shows the liquid level of oil 501. The storage chamber R1 is an example of the first storage chamber, and the oil 501 is an example of the first oil.

The accommodation chamber R2 accommodates the connection mechanism 12. Oil 502 is contained in the containment chamber R2. The line L2 in FIG. 2 shows the liquid level of the oil 502. The storage chamber R2 is an example of the third storage chamber, and the oil 502 is an example of the first oil.

The accommodation chamber R3 accommodates the final gear 38 and the differential gear 14. Oil 503 is stored in the storage chamber R3. Therefore, the oil 503 is interposed between the tooth surface of the final gear 38 and the tooth surface of the ring gear 52. The line L3 in FIG. 2 shows the liquid level of the oil 503. The storage chamber R1 is an example of the first storage chamber, and the oil 503 is an example of the second oil.

The accommodation chamber R4 accommodates the reduction mechanisms 41 and 42. Oil 504 is stored in the storage chamber R3. The line L4 in FIG. 2 shows the liquid level of the oil 504.

In the present embodiment, the oil 501 of the accommodation chamber R1 and the oil 502 of the accommodation chamber R2 are of the same type and have the same viscosity, and the oil 503 of the accommodation chamber R3 and the oil 504 of the accommodation chamber R4 are of the same type. Yes The viscosity is the same. The viscosities of oils 503 and 504 are higher than the viscosities of oils 501 and 502. Further, the thermal conductivity of the oils 501 and 502 is higher than that of the oils 501 and 504. Oils 501 and 502 are, for example, automatic transmission fluid (ATF). On the other hand, the oils 503 and 504 are, for example, differential oils.

As described above, in the present embodiment, the oils 501 and 502 and the oils 503 and 504 are different. Therefore, in the present embodiment, the seals separating the containment chambers R1 and R2 and the containment chambers R3 and R4 are sealed so as to restrict the flow of the oils 501 to 504 between the containment chambers R1 and R2 and the containment chambers R3 and R4. The portion 401 is provided in the housing 2. Specifically, the seal portion 401 is arranged on the side opposite to the X direction of the bearing B11, and restricts the flow of oils 501 to 504 in the opening 102 g. That is, the seal portion 401 is provided between the accommodation chamber R3 and the accommodation chamber R2. The seal portion 401 is, for example, an oil seal.

In the vehicle electric drive device 1 having the above configuration, the power output from the motor shaft 11b of the motor 11 is input to the input shaft 21 of the transmission 13 via the connection mechanism 12. The power input to the transmission 13 is input to the ring gear 52 of the differential gear 14 via one of the plurality of gear stages 30 (first speed gear stage 31 or second speed gear stage 32). .. The power input to the ring gear 52 is input to the drive shafts 15L and 15R via the differential mechanism. At this time, the oils 501 to 504 are stirred.

As described above, in the present embodiment, the vehicle electric drive device 1 includes a housing 2, a motor 11, a reduction mechanism 41, a reduction mechanism 42 (first transmission mechanism), a final gear 38 (pinion gear), and a differential. It includes a gear 14 and drive shafts 15L and 15R. The motor 11 has a stator 11d housed in the housing 2 and a rotor 11c housed in the housing 2. The deceleration mechanism 41 and the deceleration mechanism 42 are interposed between the input shaft 21 to which power is transmitted from the motor 11, the output shaft 22 arranged at intervals from the input shaft 21, and the input shaft 21 and the output shaft 22. It has drive gears 33 and 35 for transmitting power and driven gears 34 and 36 (plurality of gears). The final gear 38 is composed of a hypoid pinion and rotates integrally with the output shaft 22. The differential gear 14 has a ring gear 52 that is composed of a hypoid gear and meshes with the final gear 38, and is housed in the housing 2. The drive shafts 15L and 15R are housed in the housing 2, and power is transmitted from the differential gear 14. The housing 2 contains a storage chamber R1 (first storage chamber) containing the stator 11d and the rotor 11c and containing the oil 501 (first oil), and the final gear 38 and the differential gear 14 having a viscosity of oil 501. A housing chamber R3 (second storage chamber) containing oil 503 (second oil) having a viscosity higher than that of the oil 503 (second oil) is provided.

Therefore, according to the present embodiment, the oil 503 easily lubricates the tooth surface of the ring gear 52 (hypoid gear) of the differential gear 14, that is, the ring gear 52 is easily lubricated, and the oil 501 easily cools the motor 11. ..

Further, in the present embodiment, the vehicle electric drive device 1 includes a seal portion 401 provided in the housing 2. The differential gear 14 is located between the motor 11 and the reduction mechanism 41 and the reduction mechanism 42. The seal portion 401 separates the storage chamber R1 and the storage chamber R3 so as to restrict the flow of the oil 501 and the oil 503 between the storage chamber R1 and the storage chamber R3. Therefore, it is possible to prevent the oil 501 and the oil 503 from being mixed with each other.

Further, in the present embodiment, the vehicle electric drive device 1 is located between the motor 11 and the differential gear 14, and the connection mechanism 12 (second transmission) that transmits the power of the motor 11 to the reduction mechanism 41 and the reduction mechanism 42. Mechanism). The housing 2 is provided with a storage chamber R2 (third storage chamber) located between the storage chamber R1 and the storage chamber R3, which houses the connection mechanism 12 and contains the oil 502 (first oil). .. The seal portion 401 is provided between the accommodation chamber R3 and the accommodation chamber R2. Therefore, for example, even when the rotation speed of the connection mechanism 12 is higher than the rotation speed of the reduction mechanism 41 and the reduction mechanism 42, the stirring loss of the oil 502 by the connection mechanism 12 can be reduced, so that the efficiency of power transmission is high. Easy to turn into.

(First modification)
FIG. 3 is an exemplary front view of a part of the vehicle electric drive device 1 of the first modification of the embodiment.

In the first modification, the oil 501 in the containment chamber R1 is the automatic transmission fluid (ATF), and the oils 503 to 504 in the containment chambers R2 to R4 are differential oils. The viscosity of the oil 502 is the same as that of the oils 503 and 504, and is higher than the viscosity of the oil 501.

Further, in the first modification, the seal portion 401 is provided between the accommodation chamber R1 (first accommodation chamber) and the accommodation chamber R2 (third accommodation chamber). Specifically, it is provided on the opposite side of the bearing B13 in the X direction to limit the flow of oils 501 to 504 in the opening 11g. Further, a partition wall 11h is provided in the motor shaft 11b.

As described above, in the first modification, the seal portion 401 is provided between the accommodation chamber R1 and the accommodation chamber R2. Therefore, the seal portion 401 can be configured relatively simply.

(Second modification)
In this second modification, the oils 501, 502, 504 in the containment chambers R1, R2, and R4 are automatic transmission fluids (ATFs), and the oil 503 in the containment chambers R3 is differential oil.

(Third modification example)
In the third modification, the oils 501 and 504 in the accommodation chambers R1 and R4 are automatic transmission fluids (ATFs), and the oils 503 in the accommodation chambers R2 and R3 are differential oils.

In the above embodiment, the motor 11 and the drive unit 100 are located on the front side of the axle case 10 in the vehicle front-rear direction, and the transmission 13 and the transmission unit 200 are located on the rear side of the axle case 10 in the vehicle front-rear direction. Examples have been shown, but are not limited to this. That is, the motor 11 and the drive unit 100 may be located on the rear side of the axle case 10 in the vehicle front-rear direction, and the transmission 13 and the transmission unit 200 may be located on the front side of the axle case 10 in the vehicle front-rear direction.

Further, in the above embodiment, an example is shown in which the motor 11, the drive unit 100, the transmission 13 and the transmission unit 200 are located on opposite sides of the axle case 10, but the present invention is not limited to this. For example, the motor 11, the drive unit 100, the transmission 13, and the transmission unit 200 may be located on the same side of the axle case 10.

Further, in the above embodiment, an example in which the first direction is the X direction along the vehicle front-rear direction is shown, but the present invention is not limited to this. The first direction may be inclined with respect to the front-rear direction of the vehicle. That is, the motor shaft 11b, the input shaft 21, the output shaft 22, and the through drive shaft 81 may be inclined with respect to the vehicle front-rear direction as long as they are orthogonal to the vehicle width direction.

Further, in each of the above embodiments, examples of the reduction mechanism 41 and the reduction mechanism 42 as the first gear mechanism are shown, but the present invention is not limited thereto. For example, the first gear mechanism may be composed of only one reduction mechanism 41 or only one reduction mechanism 42. That is, the first gear mechanism may have a configuration in which the gear stage 30 cannot be selected. Further, the first gear mechanism may have a configuration in which the rotation speed of the input shaft 21 and the rotation speed of the output shaft 22 are the same, that is, a configuration in which deceleration and acceleration are not performed.

Although the embodiments of the present invention have been described above, the above-described embodiments are merely examples and are not intended to limit the scope of the invention. The novel embodiment described above can be implemented in various forms, and various omissions, replacements, or changes can be made without departing from the gist of the invention. Further, the above-described embodiment is included in the scope and gist of the invention, and is also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 ... Electric drive device for vehicles, 2 ... Housing, 10 ... Axle case, 11 ... Motor, 11b ... Motor shaft, 11c ... Rotor, 11d ... stator, 12 ... Connection mechanism (second transmission mechanism), 14 ... Differential gear, 15L, 15R ... drive shaft, 21 ... input shaft, 22 ... output shaft, 33, 35 ... drive gear (gear), 34, 36 ... driven gear (gear), 38 ... final gear (pinion gear), 41 ... reduction mechanism ( 1st transmission mechanism), 42 ... Deceleration mechanism (1st transmission mechanism), 401 ... Seal part, 501-504 ... Oil, R1-R4 ... Storage chamber.

Claims (4)

With the housing
A motor having a stator housed in the housing and a rotor housed in the housing.
An input shaft to which power is transmitted from the motor, an output shaft arranged at intervals from the input shaft, and a plurality of gears interposed between the input shaft and the output shaft to transmit the power. A first transmission mechanism having and housed in the housing,
A pinion gear composed of hypoid pinions and rotating integrally with the output shaft,
A differential gear that is composed of hypoid gears and has a ring gear that meshes with the pinion gear, and is housed in the housing.
A drive shaft housed in the housing and transmitting the power from the differential gear,
With
The housing contains a first storage chamber containing the stator and the rotor and containing the first oil, and a second oil containing the pinion gear and the differential gear and having a viscosity higher than that of the first oil. An electric drive device for a vehicle provided with a second storage chamber in which the vehicle is housed. A seal portion provided in the housing is provided.
The differential gear is located between the motor and the first transmission mechanism.
The seal portion separates the first accommodating chamber and the second accommodating chamber so as to restrict the flow of the first oil and the second oil between the first accommodating chamber and the second accommodating chamber. The electric drive device for a vehicle according to claim 1. It is located between the motor and the differential gear, and includes a second transmission mechanism that transmits the power of the motor to the first transmission mechanism.
The housing is provided with a third storage chamber located between the first storage chamber and the second storage chamber, which houses the second transmission mechanism and contains the second oil.
The electric drive device for a vehicle according to claim 2, wherein the seal portion is provided between the first accommodation chamber and the third accommodation chamber. It is located between the motor and the differential gear, and includes a second transmission mechanism that transmits the power of the motor to the first transmission mechanism.
The housing is provided with a third storage chamber located between the first storage chamber and the second storage chamber, which houses the second transmission mechanism and contains the first oil.
The electric drive device for a vehicle according to claim 2, wherein the seal portion is provided between the second accommodation chamber and the third accommodation chamber.

Images