CN211280623U

CN211280623U - In-wheel motor type vehicle drive device

Info

Publication number: CN211280623U
Application number: CN201921485480.XU
Authority: CN
Inventors: 森尾俊之; 田中悟
Original assignee: Aisin Seiki Co Ltd
Current assignee: Aisin Corp
Priority date: 2018-09-19
Filing date: 2019-09-06
Publication date: 2020-08-18
Anticipated expiration: 2029-09-06
Also published as: JP7135639B2; JP2020044959A; DE102019121659A1

Abstract

The utility model provides a motor type vehicle drive arrangement in wheel, it includes: an electric motor (10) comprising a motor gear (16); a counter gear (21, 121, 221) including second external teeth (21a) or internal teeth (121a) that mesh with the motor gear; a planetary gear mechanism (101); a hub (50) that transmits driving force to a wheel (3) of a vehicle wheel (1); the planetary gear mechanism is disposed at an outer side in a radial direction (R) with respect to the counter gear, and at least a part of the planetary gear mechanism is disposed in an inner space portion (3a) of the wheel, and the planetary gear mechanism includes a first ring gear (24), a second ring gear (25), and a pinion (26) including a first gear portion (27) and a second gear portion (28) having a diameter (R2) different from a diameter (R1) of the first gear portion.

Description

In-wheel motor type vehicle drive device

Technical Field

The present invention generally relates to an in-wheel motor type vehicle drive device.

Background

Conventionally, an in-wheel motor type vehicle drive device including a pinion gear is known (for example, refer to JP2008-44438A, JP2008-44438A will also be referred to as patent document 1).

According to the in-wheel motor type vehicle driving apparatus (in-wheel motor structure) described in patent document 1, an electric motor and a speed reducing mechanism are provided in a wheel (provided in a space portion surrounded by an inner peripheral surface of a rim (rim) of the wheel, to which the wheel is attached). The rotational output (driving force) of the electric motor is transmitted to the wheels via the speed reduction mechanism. Specifically, the reduction mechanism includes a counter gear mechanism and a planetary gear mechanism. The counter gear mechanism includes a small diameter drive gear disposed concentrically with the output shaft of the electric motor and a large diameter counter gear engaged with the small diameter drive gear. The small diameter drive gear is fixed to an output shaft of the electric motor by spline fitting.

The planetary gear mechanism of the in-wheel motor structure described in patent document 1 includes a sun gear, a planetary gear (pinion gear), and a ring gear. The sun gear is connected to a counter gear of the counter gear mechanism. The planet gears are disposed radially outward relative to the sun gear. The ring gear is disposed at a radially outer side with respect to the planetary gears. Thus, the planet gears are configured to engage the sun gear at a radially inner side and the ring gear at a radially outer side. The counter gear and the ring gear are arranged offset in a direction along the rotation axis.

According to the in-wheel motor structure described in patent document 1, in association with the rotation of the electric motor, the small-diameter drive gear of the counter gear mechanism rotates and the large-diameter counter gear engaged with the small-diameter drive gear rotates. Therefore, the first stage of deceleration is performed. Further, in association with the rotation of the counter gear, the sun gear connected to the counter gear rotates. In association with the rotation of the sun gear, the planetary gears revolve around the sun gear at the radially outer side while the planetary gears rotate around the axes of the planetary gears. The second stage of reduction is performed by rotation of the planetary gear. Then, the revolution or orbital motion of the planetary gear is transmitted to the driving force transmission member spline-fitted to the carrier via the carrier. As a result, the wheels rotate together with the driving force transmitting member.

According to the in-wheel motor structure described in the above-mentioned patent document 1, it is desirable to improve the reduction ratio while performing the reduction of the first stage due to the rotation of the large-diameter counter gear engaged with the small-diameter drive gear and the reduction of the second stage by the rotation of the planetary gear on the axis of the planetary gear itself.

Therefore, there is a need for an in-wheel motor type vehicle drive device capable of improving a reduction ratio.

SUMMERY OF THE UTILITY MODEL

According to an aspect of the present invention, an in-wheel motor type vehicle drive device includes: an electric motor including a motor gear provided with first external teeth, the electric motor being configured to generate a driving force that drives a wheel; a counter gear including second outer teeth engaged with the first outer teeth of the motor gear or inner teeth engaged with the first outer teeth of the motor gear; a planetary gear mechanism to which a driving force of the counter gear is transmitted; a hub configured to transmit a driving force of the planetary gear mechanism to a wheel of a wheel; the planetary gear mechanism is disposed at an outer side in a radial direction with respect to the counter gear, and at least a part of the planetary gear mechanism is disposed in the inner space portion of the wheel; and the planetary gear mechanism includes a first ring gear, a second ring gear, and a pinion gear including a first gear portion engaged with the first ring gear and a second gear portion engaged with the second ring gear, the second gear portion having a diameter different from a diameter of the first gear portion.

According to the above structure, the planetary gear mechanism includes the first ring gear, the second ring gear, and the pinion gear. The pinion gear includes a first gear portion engaged with the first ring gear and a second gear portion engaged with the second ring gear. The second gear portion has a diameter different from a diameter of the first gear portion. Therefore, the reduction gear ratio can be increased as compared with the planetary gear mechanism of the in-wheel motor structure described in the above-mentioned patent document 1. Further, since the planetary gear mechanism is disposed at the outer side in the radial direction with respect to the counter gear, and at least a part of the planetary gear mechanism is disposed in the inner space portion of the wheel, it is possible to restrict the size of the vehicle drive device from increasing in the axial direction.

According to another aspect of the present invention, the counter gear and the first ring gear are disposed to overlap each other in a direction orthogonal to the rotation axis of the wheel.

According to the above structure, unlike the case where the counter gear and the first ring gear are provided so as to be offset in the direction along the rotational axis of the wheel, it is possible to restrict an increase in the length of the vehicle drive device in the direction along the rotational axis of the wheel.

According to another aspect of the present invention, the rotation axis of the electric motor is disposed at an inner side in the radial direction with respect to the rotation axis of the pinion.

According to the above structure, unlike the case where the rotation axis of the electric motor is disposed at the outer side in the radial direction with respect to the rotation axis of the pinion gear, it is possible to restrict an increase in the length of the vehicle drive device in the radial direction (i.e., the direction orthogonal to the rotation axis).

According to another aspect of the present invention, the hub is disposed at an inner side in a radial direction with respect to a rotation axis of the pinion.

According to the above structure, the diameter of the hub can be reduced as compared with the case where the hub is disposed at the outer side in the radial direction with respect to the rotation axis of the pinion. The diameter of the bearing configured to be included in the hub can thereby be reduced, and therefore the friction of the bearing can be reduced. Further, for example, the diameter of an oil seal (annular seal) provided around the bearing can be reduced, and therefore resistance due to friction of the oil seal can be reduced.

According to another aspect of the present invention, the in-wheel motor type vehicle driving apparatus further includes a flange portion that connects the hub and the second ring gear to each other, and movement of the second ring gear in the axial direction relative to the flange portion is restricted by the retaining ring.

According to the above structure, the second ring gear and the flange portion can move relative to each other within a certain range, unlike the case where the second ring gear and the flange portion are fixed to each other by welding, for example. Therefore, even in the case where the hub is deformed by the stress applied to the wheel, the inclination of the rotation axis of the second ring gear due to the deformation of the hub can be restricted. So that it is possible to restrict the occurrence of deterioration in the engagement or meshing of the second ring gear and the pinion with the second gear portion engaged or meshed with the second ring gear.

Drawings

The foregoing and additional features and characteristics of the present invention will become more apparent from the following detailed description considered with reference to the accompanying drawings, in which:

fig. 1 is a cross-sectional view of an in-wheel motor type vehicle drive apparatus according to a first embodiment disclosed herein;

fig. 2 is a view schematically showing an electric motor (motor gear), a counter gear, and a pinion gear according to an embodiment;

fig. 3 is a view showing a structure of a carrier according to an embodiment;

FIG. 4 is an enlarged view showing a portion of FIG. 1;

fig. 5 is a speed diagram of the in-wheel motor type vehicle drive apparatus according to the first embodiment;

fig. 6 is a view schematically showing an in-wheel motor type vehicle drive device according to a second embodiment disclosed herein;

fig. 7 is a view schematically showing an in-wheel motor type vehicle drive device according to a third embodiment disclosed herein; and

fig. 8 is a speed diagram of an in-wheel motor type vehicle driving device according to a third embodiment.

Detailed Description

Embodiments disclosed herein will be described below with reference to the accompanying drawings.

The structure of an in-wheel motor type vehicle driving device 100 according to a first embodiment will be described with reference to fig. 1 to 5.

In this specification, the "axial direction (direction of the rotation axis)" corresponds to a direction (direction X) along the rotation axis C1 of the wheel 1, as shown in fig. 1. The "radial direction" corresponds to a direction (direction R) orthogonal to the rotation axis C1 of the wheel 1. The "inner side in the radial direction" corresponds to a direction toward the rotation axis C1 along the radial direction (direction R1). The "outer side in the radial direction" corresponds to a direction toward the outer side of the rotation axis C1 along the radial direction (direction R2).

As shown in fig. 1, the wheel 1 includes a wheel 3, and the tire 2 is mounted on the wheel 3. The wheel 3 has a substantially cylindrical shape. An electric motor 10, a speed reduction mechanism 20, and a hub 50 configured to generate a driving force for driving the wheel 1 are provided in the interior (interior space portion 3a) of the wheel 3 having a substantially cylindrical shape.

In the inner space portion 3a of the wheel 3, the electric motor 10 is disposed at the inner side of the vehicle (at the side of the direction X1). The rotation axis C2 of the electric motor 10 is provided offset, i.e., deviated, toward the upper direction side with respect to the rotation axis C1 of the wheel 1. Specifically, as shown in fig. 2, the rotation axis C2 of the electric motor 10 is offset in an obliquely upward direction (for example, in an angular direction of approximately forty-five degrees with respect to the horizontal line) with respect to the rotation axis C1 of the wheel 1. Therefore, a portion not occupied by the electric motor 10 is formed at the lower side of the inner space portion 3a of the wheel 3. A ball joint 4 serving as one end of a rotation center when the wheel 1 is turned is provided in the inner space portion 3a at a lower direction side of the wheel 3 with respect to the rotation axis C1 of the wheel 1. A terminal block 5 configured to supply electric power to the electric motor 10 is provided in the inner space portion 3a at an upper direction side of the wheel 3.

As shown in fig. 1, the electric motor 10 includes a stator 11, and a coil 12 provided at the stator 11, and a rotor 13 provided at an inner side in a radial direction with respect to the stator 11. The stator 11 is fixed to a first housing 31, and the first housing 31 is provided to cover the electric motor 10. A shaft 14 serving as an output shaft is provided at the rotor 13. As described above, the rotation axis C2 of the shaft 14 is offset to the obliquely upper side with respect to the rotation axis C1 of the wheel 1. A portion of the shaft 14 at the side of the direction X1 is supported by a bearing portion 15 (bearing) provided at the first housing 31. The portion of the shaft 14 at the side of the direction X2 is supported by another bearing 15 (another bearing) provided at a third housing 33, the third housing 33 being provided between the first housing 31 and the second housing 32, the second housing 32 being provided so as to cover the speed reduction mechanism 20. The motor gear 16 includes first external teeth 16a, and the first external teeth 16a are provided at a portion of the shaft 14 at the side of the direction X2.

In the first embodiment, the rotation axis C2 of the electric motor 10 is disposed at the inner side in the radial direction with respect to the rotation axis C3 of the pinion 26 (the rotation axis of the pinion 26). Specifically, the rotation axis C2 of the electric motor 10 is disposed between the rotation axis C1 of the wheel 1 and the rotation axis C3 of the pinion 26 (the rotation axis of the pinion 26).

The driving force of the electric motor 10 is configured to be transmitted to the wheels 3 via the speed reduction mechanism 20. The reduction mechanism 20 includes a counter gear 21, a carrier 22, a ring gear 23, and a pinion gear 26.

The counter gear 21 includes second external teeth 21a that mesh with the first external teeth 16a of the motor gear 16. The counter gear 21 has a larger diameter than the motor gear 16. That is, the number of teeth of the counter gear 21 is larger than that of the motor gear 16. The axis of rotation of the counter gear 21 coincides with the axis of rotation C1 of the wheel 1. The counter gear 21 is disposed at the outer side in the radial direction with respect to the shaft 6, and the shaft 6 rotates about the rotation axis C1 of the wheel 1.

As shown in fig. 1 and 3, the carrier 22 is provided with a cylindrical portion 42, the cylindrical portion 42 having a cylindrical shape and supporting the pinion gears 26 such that the pinion gears 26 can rotate. In this embodiment, for example, three columnar portions 42 are provided at the carrier 22. The carrier 22 is configured to rotate as the counter gear 21 rotates. Specifically, the driving force of the counter gear 21 is transmitted to a radially inner portion (ring portion) 22a of the carrier 22, and thus the carrier 22 rotates together with the rotation of the counter gear 21. The carrier 22 includes a pair of support plates 41, each of the pair of support plates 41 having a ring shape. One of the pair of support plates 41 is positioned at the side of the direction X1 with respect to the pinion 26 and the other support plate is positioned at the side of the direction X2 with respect to the pinion 26 such that the support plate 41 sandwiches the pinion 26 between the support plates 41. The support plates 41 are connected to each other by bridge members 22 b. The radially inner portion (ring portion) 22a of the carrier 22 and the bridge member 22b are connected to each other by a connecting member 22 c. In this embodiment, a plurality of (e.g., three) bridge members 22b are provided. The bridge members 22b and the columnar portions 42 each having a cylindrical columnar shape are arranged on the circumference alternately with each other in the circumferential direction.

As shown in fig. 1, the pinion 26 is rotatably supported by a columnar portion 42 connected to the pair of support plates 41 each having an annular shape. A plurality of (three in this embodiment) pinion gears 26 are provided. In the first embodiment, each of the pinions 26 includes a first gear portion 27 and a second gear portion 28. The first gear portion 27 is engaged with, i.e., meshed with, a first ring gear 24 which will be described later. The second gear portion 28 is engaged with a second ring gear 25 which will be described later. The diameter r2 of the second gear portion 28 is different from the diameter r1 of the first gear portion 27 (e.g., the diameter r2 is smaller than the diameter r 1). The rotational axis C3 of the first gear portion 27 and the rotational axis C3 of the second gear portion 28 coincide with each other. The first gear portion 27 is disposed at the side of the direction X1 with respect to the second gear portion 28. The number of teeth of the first gear portion 27 and the number of teeth of the second gear portion 28 are different from each other.

The ring gear 23 is disposed at the outer side in the radial direction with respect to the counter gear 21. The ring gear 23 includes a first ring gear 24 and a second ring gear 25 serving as a rotatable output shaft. The first ring gear 24 is fixed to the second housing 32. That is, the first ring gear 24 does not rotate. The first ring gear 24 is disposed at the side of the direction X1 with respect to the second ring gear 25. The pinion 26 is disposed at the inner side in the radial direction with respect to the ring gear 23. The internal teeth 24a of the first ring gear 24 are configured to mesh with the external teeth 27a of the first gear portion 27 of the pinion gear 26. The internal teeth 25a of the second ring gear 25 are configured to mesh with the external teeth 28a of the second gear portion 28 of the pinion gear 26. The axis of rotation of the first ring gear 24 and the axis of rotation of the second ring gear 25 coincide with the axis of rotation C1 of the wheel 1.

The first ring gear 24, the second ring gear 25, and the pinion 26 form a planetary gear mechanism 101. The planetary gear mechanism 101 is disposed at the outer side in the radial direction with respect to the counter gear 21, and at least a part of the planetary gear mechanism 101 is disposed in the internal space portion 3a of the wheel 3 (for example, in the first embodiment, the entire planetary gear mechanism 101 is disposed in the internal space portion 3 a).

In the first embodiment, the counter gear 21 and the first ring gear 24 are disposed so as to overlap each other in a direction (radial direction) orthogonal to the rotation axis C1 of the wheel 1. The counter gear 21, the motor gear 16, the first gear portion 27 of the pinion gear 26, and the first ring gear 24 are disposed in the stated order from the inner side in the radial direction toward the outer side in the radial direction.

The hub 50 is configured to transmit the driving force of the planetary gear mechanism 101 to the wheel 3 of the wheel 1. The hub 50 is disposed at the outer side in the radial direction with respect to the shaft 6. The hub 50 includes a radially inner member 51 provided at the shaft 6, a radially outer member 52 provided at an outer side in the radial direction with respect to the radially inner member 51, and a bearing 53 provided between the radially inner member 51 and the radially outer member 52. An oil seal 54 is provided at each of a portion of the bearing 53 at the side of the direction X1 and another portion of the bearing 53 at the side of the direction X2, the oil seal 54 sealing the oil for smoothly rotating the bearing 53.

The hub 50 is disposed at the inner side in the radial direction with respect to the rotation axis C3 of each of the pinions 26. The hub 50 and the second gear portion 28 of each of the pinions 26 are disposed so as to overlap with each other in a direction (radial direction) orthogonal to the rotation axis C1 of the wheel 1.

As shown in fig. 4, in the first embodiment, the hub 50 and the second ring gear 25 are connected to each other through the flange portion 55. The second ring gear 25 is fixed with respect to the flange portion 55 by using a snap ring 60. Specifically, one end portion (an end portion at the inner side in the radial direction) of the flange portion 55 is spline-fitted or spline-engaged with the radially outer member 52 and is thus fixed to the radially outer member 52. Portions 25c of the internal teeth 25a of the second ring gear 25 are shaved or cut and used as splines. The other end portion (end portion at the outer side in the radial direction) of the flange portion 55 is engaged with the portion 25 c. The second ring gear 25 includes a groove portion 25b provided in the vicinity of the portion 25c serving as a spline. The snap ring 60 is disposed at the groove portion 25 b. The flange portion 55 is restricted from moving in the circumferential direction relative to the second ring gear 25 by splines, and is restricted from moving in the axial direction relative to the second ring gear 25 by a snap ring 60. That is, the second ring gear 25 is restricted from moving in the axial direction relative to the flange portion 55 by the snap ring 60. Therefore, even in the case where the hub 50 is deformed by the stress applied to the wheel 1 and the flange portion 55 is inclined with respect to the radial direction in association with the deformation of the hub 50, the inclination includes only a low or small influence on the second ring gear 25. Snap ring 60 is an example of a retaining ring of the present invention.

As shown in fig. 1, the radially outer member 52 of the hub 50 and the wheel 3 are fixed (fastened) to each other by bolts 61.

A seal 62 is provided between the second housing 32 provided to cover the reduction mechanism 20 and the radially outer member 52 of the hub 50.

In the first embodiment, the driving force of the electric motor 10 is configured to be transmitted to the second ring gear 25 serving as an output shaft via the counter gear 21, the carrier 22, and the pinion gear 26. Specifically, the counter gear 21 engaged with the motor gear 16 rotates in association with the rotation of the electric motor 10. Therefore, the first stage of deceleration is performed. The carrier 22 rotates in association with the rotation of the counter gear 21. In association with the rotation of the carrier 22, the first gear portion 27 of each pinion 26 revolves or orbits (orbit) at the radially inner side of the first ring gear 24 while the pinion 26 rotates around the rotational axis of the pinion 26. Since the first ring gear 24 is stationary, the pinion 26 orbits such that the second gear portion 28, having a smaller diameter r2, orbits along the second ring gear 25. Therefore, the deceleration is performed according to the gear ratio of the first gear portion 27 and the second gear portion 28 of the pinion 26. Then, the wheel 3 and the radially outer member 52 of the hub 50 rotate together in association with the rotation of the second ring gear 25.

As shown in fig. 5, it is assumed that the pinion 26 (the first gear portion 27 and the second gear portion 28) rotates at the speed 1 with the first ring gear 24 fixed (speed 0). Then the second ring gear 25 is decelerated to a speed between speed 1 and speed 0.

The following effects can be obtained in the first embodiment.

In the first embodiment, as described above, the planetary gear mechanism 101 includes the first ring gear 24, the second ring gear 25, and the pinion gears 26, the pinion gears 26 each include the first gear portion 27 and the second gear portion 28, the first gear portion 27 is engaged or meshed with the first ring gear 24, and the second gear portion 28 is engaged or meshed with the second ring gear 25 and has a diameter different from that of the first gear portion 27. Therefore, the reduction gear ratio can be improved in the first embodiment as compared with the planetary gear mechanism of the in-wheel motor structure described in the above-mentioned patent document 1. Further, since the planetary gear mechanism 101 is disposed at the outer side in the radial direction with respect to the counter gear 21, and at least a part of the planetary gear mechanism 101 is disposed in the internal space portion 3a of the wheel 3, an increase in the size of the vehicle drive device 100 in the axial direction is restricted.

Unlike the case where the counter gear 21 and the first ring gear 24 are provided so as to be offset in the direction along the rotation axis C1 of the wheel 1, in the first embodiment, it is possible to restrict an increase in the length of the vehicle drive device 100 in the direction along the rotation axis C1 of the wheel 1.

Unlike the case where the rotation axis C2 of the electric motor 10 is disposed at the outer side in the radial direction with respect to the rotation axis C3 of the pinion 26, in the first embodiment, it is possible to restrict an increase in the length of the vehicle drive device 100 in the radial direction (i.e., the direction orthogonal to the rotation axis C1 of the wheel 1).

In the first embodiment, the diameter of the hub 50 can be reduced as compared with the case where the hub 50 is disposed at the outer side in the radial direction with respect to the rotation axis C3 of the pinion 26. So that the diameter of the bearing 53 included in the hub 50 can be reduced and thus the friction of the bearing 53 can be reduced. Further, the diameter of the oil seal 54 (annular seal) provided around the bearing 53 can be reduced, and therefore the resistance due to the friction of the oil seal 54 can be reduced.

Unlike the case where the second ring gear 25 and the flange portion 55 are fixed to each other by welding, for example, in the first embodiment, the second ring gear 25 and the flange portion 55 can move relative to each other to some extent or within a certain range. Therefore, even in the case where the hub 50 is deformed by the stress applied to the wheel 1, the inclination of the rotation axis of the second ring gear 25 due to the deformation of the hub 50 is restricted. It is thereby possible to restrict the occurrence of deterioration in the engagement of the second ring gear 25 and the second gear portion 28 of the pinion 26, which is engaged with the second ring gear 25.

In the first embodiment, the ball joint 4 that turns the wheel 1 is provided in the interior of the wheel 3 at the lower direction side with respect to the rotation axis C1 of the wheel 1, that is, at the side opposite to the upper direction side where the electric motor 10 is provided. So that the ball joint 4 can be easily provided inside the wheel 3 at the lower direction side where the electric motor 10 is not provided.

The structure of an in-wheel motor type vehicle driving device 200 according to the second embodiment will be described with reference to fig. 6. The second embodiment differs from the first embodiment in that the teeth of the counter gear 121 that engage with the first external teeth 16a of the motor gear 16 are different.

The vehicle drive device 200 is configured such that the internal teeth 121a of the counter gear 121 mesh with the first external teeth 16a of the motor gear 16. Therefore, the counter gear 121 has a larger diameter than the counter gear 21 of the first embodiment. Further, the motor gear 16, the counter gear 121, the pinion gear 26, and the ring gear 23 are disposed in the stated order from the inner side in the radial direction toward the outer side in the radial direction.

Other configurations and structures, speed diagrams (refer to fig. 5), and effects of the second embodiment are similar to those of the first embodiment.

The structure of an in-wheel motor type vehicle driving device 300 according to a third embodiment will be described with reference to fig. 7 and 8. Unlike the first and second embodiments in which the driving force of the counter gear 21 is transmitted to the carrier 22, in the third embodiment, the driving force of the counter gear 221 is transmitted to the first ring gear 224.

The in-wheel motor type vehicle driving device 300 is configured such that the counter gear 221 (internal teeth) is engaged with the motor gear 16 (external teeth). The counter gear 221 is connected to the first ring gear 224, and thus the first ring gear 224 rotates in association with the rotation of the counter gear 221. The first gear portion 27 (external teeth) of the pinion 26 is engaged with the first ring gear 224 (internal teeth). The pinion gears 26 are rotatably supported by a carrier 222 fixed to the second housing 32. The second ring gear 25 (internal teeth) is engaged with the second gear portion 28 (external teeth) of the pinion 26. The driving force of the electric motor 10 is configured to be transmitted to the second ring gear 25 serving as an output shaft via the counter gear 221, the first ring gear 224, the pinion gear 26 supported by the fixed carrier 222.

As shown in fig. 8, it is assumed that the first ring gear 224 rotates at a speed 1 with the pinion 26 (the first gear portion 27 and the second gear portion 28) fixed (speed 0). Then the second ring gear 25 is decelerated to a speed between speed 1 and speed 0.

Other configurations and structures, and effects of the third embodiment are similar to those of the first embodiment.

Modified examples the foregoing embodiments disclosed herein are examples and are not provided to limit the scope of the present invention in all respects. The scope of the present invention is defined by the scope of the claims, not by the description of the foregoing embodiments, and includes all changes (modification examples) within the scope of the claims and their equivalents.

For example, the foregoing embodiment shows an example case where the counter gear and the first ring gear are provided so as to overlap each other in a direction orthogonal to the rotation axis of the wheel, however, the present invention is not limited thereto. For example, the counter gear and the first ring gear may be arranged offset in the direction of the rotational axis of the wheel.

The foregoing embodiment shows an example case where the second ring gear is fixed with respect to the flange portion by using the snap ring, however, the present invention is not limited thereto. For example, the second ring gear may be fixed with respect to the flange portion by using a retaining ring other than the snap ring.

The foregoing embodiment shows an example case where the rotational axis of the electric motor is offset toward the upper direction side with respect to the rotational axis of the wheel and the ball joint is provided at the lower direction side with respect to the rotational axis of the wheel, however, the present invention is not limited thereto. For example, the rotational axis of the electric motor may be provided offset toward the lower direction side with respect to the rotational axis of the wheel, and/or the ball joint may be provided at the upper direction side with respect to the rotational axis of the wheel.

The foregoing embodiment shows an example case where the diameter r2 of the second gear portion 28 is smaller than the diameter r1 of the first gear portion 27, however, the present invention is not limited thereto. For example, the diameter r2 of the second gear portion 28 may be larger than the diameter r1 of the first gear portion 27.

Other structures and configurations described below are conceivable in addition to the in-wheel motor type vehicle drive device of the foregoing embodiment.

(addition item 1) according to the in-wheel motor type

vehicle driving device

100, 200, 300 described above, the pinion 26 is disposed at the inner side in the radial direction with respect to the first ring gear 24 and the second ring gear 25 such that the pinion 26 is engaged with the internal teeth 24a of the first ring gear 24 and the internal teeth 25a of the second ring gear 25.

(addition item 2) according to the in-wheel motor type

vehicle driving apparatus

100, 200, 300 described above, the rotation axis C2 of the electric motor 10 is disposed offset toward one of the upper direction side and the lower direction side with respect to the rotation axis C1 of the wheel 1, and the ball joint 4 serving as one end of the rotation center when the wheel 1 is turned is disposed in the internal space portion 3a at the other of the upper direction side and the lower direction side with respect to the rotation axis C1 of the wheel 1.

(addition item 3) the in-wheel motor type vehicle driving device 200 described above further includes a first carrier that supports the pinion gear 26 so that the pinion gear 26 is rotatable, the first carrier rotating together with the rotation of the counter gear 21, wherein the driving force of the electric motor 10 is configured to be transmitted to the second ring gear 25 serving as the output shaft 14 via the counter gear 21, the first carrier, and the pinion gear 26.

(addition item 4) the in-wheel motor type vehicle driving apparatus 300 described above further includes a second carrier that supports the pinion 26 such that the pinion 26 is rotatable, the second carrier being fixed to a case that covers the pinion 26, wherein the driving force of the electric motor 10 is configured to be transmitted to the second ring gear 25 serving as the output shaft 14 via the counter gear 221, the first ring gear 224, and the pinion 26 supported by the fixed second carrier.

Claims

1. An in-wheel motor type vehicle drive device (100, 200, 300) comprising:

an electric motor (10), the electric motor (10) including a motor gear (16) provided with first external teeth (16a), the electric motor (10) being configured to generate a driving force that drives a wheel (1);

a counter gear (21, 121, 221), the counter gear (21, 121, 221) comprising second external teeth (21a) meshing with the first external teeth (16a) of the motor gear (16) or internal teeth (121a) meshing with the first external teeth (16a) of the motor gear (16);

a planetary gear mechanism (101) to which a driving force of the counter gear (21, 121, 221) is transmitted;

a hub (50), the hub (50) being configured to transmit a driving force of the planetary gear mechanism (101) to a wheel (3) of the wheel (1);

the planetary gear mechanism (101) is disposed at an outer side in a radial direction (R) with respect to the counter gear (21, 121, 221), and at least a part of the planetary gear mechanism (101) is disposed in an inner space portion (3a) of the wheel (3); and is

Characterized in that the planetary gear mechanism (101) comprises a first ring gear (24), a second ring gear (25) and a pinion (26), the pinion (26) comprising a first gear portion (27) engaged with the first ring gear (24) and a second gear portion (28) engaged with the second ring gear (25), the second gear portion (28) having a diameter (r2) different from a diameter (r1) of the first gear portion (27).

2. The in-wheel motor type vehicle driving apparatus (100, 200, 300) according to claim 1, wherein the counter gear (21, 121, 221) and the first ring gear (24) are disposed so as to overlap each other in a direction orthogonal to a rotation axis (C1) of the wheel (1).

3. The in-wheel motor type vehicle driving apparatus (100, 200, 300) according to claim 1 or 2, characterized in that a rotation axis (C2) of the electric motor (10) is provided at an inner side in the radial direction (R) with respect to a rotation axis (C3) of the pinion gear (26).

4. The in-wheel motor type vehicle driving apparatus (100, 200, 300) according to claim 1 or 2, characterized in that the hub (50) is provided at an inner side in the radial direction (R) with respect to a rotation axis (C3) of the pinion gear (26).

5. The in-wheel motor type vehicle driving apparatus (100, 200, 300) according to claim 1 or 2, characterized by further comprising:

a flange portion (55), the flange portion (55) connecting the hub (50) and the second ring gear (25) to each other, and

movement of the second ring gear (25) in the axial direction (X) relative to the flange portion (55) is restricted by a retaining ring (60).