JP2018028364A - Vehicle driving unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the elongation of a vehicle drive unit in the axial direction and to narrow mounting space in the vehicle width direction.SOLUTION: A vehicle driving unit comprises reduction gears 3L, 3R arranged between electric motors 2L, 2R, and a gear device 30 which is assembled into the reduction gears and distributes torque of the electric motors to left and right wheels. The reduction gears have intermediate gear shafts 13l, 13r which are arranged between input gear shafts and output gear shafts 14L, 14R, and have input-side large-diameter gears 13a and output-side small-diameter gears 13b. Rotor shafts 12L, 12R of the electric motors have hollow structures. The output gear shafts passes through the rotor shafts 12L, 12R on the same axis. The gear device 30 is composed of a planetary gear mechanism which is arranged coaxially with the intermediate gear shafts 13L, 13R. Idler gears 70, 71 are arranged between the input-side large-diameter gears 13a and input gears 12a, and between the output-side small-diameter gears 13b and output gears 14a, and a part of the gear device 30 overlaps on outer diameter faces of the electric motors.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle drive device capable of amplifying a torque difference and transmitting drive torque from two independent electric motors to left and right drive wheels.

  In vehicles such as electric vehicles, electric motors are arranged on the left and right drive wheels, respectively, and each electric motor is controlled independently to give an appropriate drive torque difference between the left and right drive wheels. It is known to control. For example, when each electric motor is independently connected to the left and right drive wheels via a speed reducer, the rotation speed of each electric motor is reduced by the speed reducer and the output torque of each electric motor ( The driving force is increased by each reduction gear and transmitted to the left and right drive wheels. Here, in order to make the vehicle turn right and turn left in the same manner, each electric motor has the same output characteristics, and each reduction gear has the same reduction ratio.

  The output torques of the left and right electric motors transmitted to the left and right drive wheels are increased according to the reduction ratio of the speed reducer. However, the ratio of the difference between the output torques of the left and right drive wheels is the same as the ratio of the difference between the output torques of the left and right electric motors because the reduction ratio of the left and right reduction gears is the same. The ratio of the torque difference is not increased.

  However, in order to achieve smooth turning of the vehicle and to suppress changes in vehicle behavior such as extreme understeer and extreme oversteer, the left and right drive is more than the ratio of the difference in output torque applied from the left and right electric motors. It may be effective to increase the ratio of the difference in output torque transmitted to the wheels.

  Patent Document 1 and Patent Document 2 include a gear device in which two three-element and two-degree-of-freedom planetary gear mechanisms are coaxially combined between two electric motors and left and right drive wheels. A vehicle drive device is disclosed that can amplify the difference between torques applied to the left and right driving wheels and amplify the difference. In the vehicle drive devices described in Patent Literature 1 and Patent Literature 2, it is possible to obtain a driving torque difference larger than the output torque difference given from the left and right electric motors.

  Moreover, in patent document 1 and patent document 2, it does not mention concretely about arrangement | positioning of the gear apparatus in a vehicle drive device. The applicant of the present application has already filed a patent application for a vehicle drive device in which the gear device for amplifying the torque difference is reduced in size and weight (Japanese Patent Application No. 2006-023529).

  The vehicle drive device (prior application example) for which the applicant of the present application has applied for a patent has the configuration shown in FIGS. 16 and 17.

  As shown in FIG. 16, the vehicle drive device 201 of the prior application example includes two electric motors 202L and 202R that are mounted on the vehicle and can be controlled independently, two electric motors 202L and 202R, and left and right drive wheels. A gear device 300 that is provided between the two electric motors 202L and 202R and distributes the torques of the two electric motors 202L and 202R to the left and right wheels, and speed reducers 203L and 203R that transmit the torques of the two electric motors 202L and 202R to the drive wheels. Yes. The reduction gears 203L and 203R are connected to electric motors 202L and 202R, input gear shafts 212L and 212R having an input gear 212a, output gear shafts 214L and 214R connected to driving wheels and having an output gear 214a, and an input And intermediate gear shafts 213L and 213R that transmit power between the gear shafts 212L and 212R and the output gear shafts 214L and 214R. The intermediate gear shafts 213L and 213R are provided with an input-side large-diameter gear 213a that meshes with the input gear 212a and an output-side small-diameter gear 213b that meshes with the output gear 214a.

  The two electric motors 202L and 202R are electric motors having the same output characteristics and are accommodated in the motor housings 204L and 204R.

  The input gear shafts 212L and 212R, the intermediate gear shafts 213L and 213R, and the output gear shafts 214L and 214R are offset from each other.

As shown in FIGS. 16 and 17, the gear device 300 that distributes the torque from the two electric motors 202L and 202R to the left and right wheels is coaxial with a pair of left and right intermediate gear shafts 213L and 213R arranged coaxially. It consists of a planetary gear mechanism with three elements and two degrees of freedom in combination. Planetary gear mechanism, the internal gear R _L, and R _R, the internal gear R _L, R _R and planet carrier C _L provided coaxially, and C _R, the internal gear R _L, on R _R coaxial provided sun gear S _L, S _R, a plurality of planetary gears P _L as a revolution gear, P and a _R, one of the planet carrier of the two planetary gear mechanism C _L and the other of the sun gear S _R It has a first coupling member 231 for coupling the door, and a second coupling member 232 for coupling the one of the sun gear S _L and the other planet carrier C _R, an intermediate gear shaft in the gear device 300 and coaxially 213L, the 213R, an input-side large-diameter gear 213a meshing with the input gear 212a, a planet carrier C _L of the planetary gear mechanism, is connected to the C _R, it provided an output-side small-diameter gear 213b meshing with the output gear 214a, the planetary carrier C _L, both ends of the C _R rolling bearings 219a It is a structure that is rotatably supported on the housing 209 for accommodating the gear 300 by 219b.

In this prior application example, as described above, the sun gears S _L and S _R constituting the two planetary gear mechanisms of the gear device 300 are provided in order to arrange the gear device 300 on the intermediate gear shafts 213L and 213R of the vehicle drive device 201. , Planetary carriers C _L , C _R , planetary gears P _L , P _R , and internal gears R _L , R _R installation space and intermediate gear shafts 213L, 213R are supported to support the planet carriers C _L , C _R at both ends. Installation space for the bearings 219a and 219b is required, and the axial dimension is increased.

  In the structure in which the electric motors 202L and 202R and the output gear shafts 214L and 214R are offset, the portions of the electric motors 202L and 202R are the longest in the axial direction. In the vehicle driving apparatus shown in FIGS. 16 and 17, the input gear 212a connected to the electric motors 202L and 202R is smaller than the stator diameter of the electric motors 202L and 202R. The gear device 300 installed on the shafts 213L and 213R overlaps in the axial direction. For this reason, the electric motors 202L and 202R and the gear device 300 are inevitably arranged in the axial direction, and the length of the electric motors 202L and 202R in the axial direction is smaller than that of the speed reducer without the gear device 300. Longer.

Moreover, when these vehicle drive devices are applied to passenger cars, they are often used in two-stage deceleration because of the relationship between the rotation speed of the electric motor and the wheel rotation speed. For example, when the maximum rotation speed of the motor is 10000 min ⁻¹ , the wheel diameter is 630 mm, and the maximum vehicle speed is 180 km / h, the wheel rotation speed is 1516 min ⁻¹ , and the reduction ratio in this case is 10000 / 1516≈6.596. . If one tries to achieve such a high reduction ratio with a one-stage reduction, the large-diameter gear becomes large, and the service angle of the drive shaft is shortened by increasing the service angle, or the minimum of the reduction gear housing of the large-diameter gear section. There are disadvantages such as low ground clearance and easy contact with the ground due to unevenness of the ground. Therefore, it is common to reduce the large-diameter gear by two-stage reduction.

  Also in the vehicle drive device described in Patent Documents 1 and 2 and the vehicle drive device of the prior application example, a reduction gear having two-stage reduction is disclosed.

JP 2015-21594 A Japanese Patent No. 4907390

  As described above, the gear device 300 requires an axial length, and the gear device 300 and the electric motors 202L and 202R overlap in the axial direction, whereby the physique of the vehicle drive device 201 becomes longer in the axial direction. For this reason, it is necessary to secure a wide length in the vehicle width direction of the mounting space of the vehicle drive device in the vehicle.

  If the mounting space is wide in the vehicle width direction, the vehicle width becomes wide and the handling of the vehicle in a narrow alley becomes worse. Further, when the vehicle drive device is mounted on the steering wheel, if the vehicle drive device is long in the vehicle width direction, the steering angle is limited, and the turning ability of the vehicle is deteriorated. Furthermore, the structure and arrangement of the suspension device (especially the arm length in the vehicle width direction) is limited, which may lead to disadvantages such as reduced ride comfort and handling stability.

  Further, the reduction gears in the vehicle drive device described in Patent Documents 1 and 2 and the vehicle drive device of the prior application example are all arranged in parallel and offset from each other. If all the gear shafts of the two-stage reduction are arranged parallel and offset, the size of the vehicle drive device in the direction perpendicular to the gear shaft of the reduction gear becomes large. For this reason, the installation space of the vehicle drive device occupying the vehicle body space is increased, and there is a problem that a passenger compartment or a passenger compartment space on which luggage is placed is reduced. In the vehicle drive device, it is desired that the vehicle drive device is also small in the direction perpendicular to the axis (radial direction).

  Therefore, the present invention suppresses the vehicle drive device from becoming longer in the axial direction, can reduce the mounting space in the vehicle width direction, and also reduces the dimension in the direction (radial direction) perpendicular to the gear shaft of the speed reducer. Thus, it is an object to reduce the size of the vehicle drive device.

  In order to solve the above problems, the present invention provides two electric motors mounted on a vehicle and independently controllable, two speed reducers disposed between the two electric motors, and the two speed reducers. And a gear drive that distributes torque from two electric motors to the left and right wheels, wherein the speed reducer includes an input gear provided coaxially with a rotor shaft of the electric motor. An output gear shaft including an output gear coupled to the drive wheel, and an intermediate gear shaft provided between the input gear shaft and the output gear shaft and including an input-side large-diameter gear and an output-side small-diameter gear. A hollow structure that penetrates the rotor shaft of the electric motor in the axial direction, and the input gear is provided on the outer periphery of the end of the inboard side of the rotor shaft of the hollow structure, and an output gear shaft connected to the drive wheel The input gear The gear device is a three-element 2 provided coaxially with a pair of left and right intermediate gear shafts having the input-side large-diameter gear and the output-side small-diameter gear. It consists of a planetary gear mechanism with a degree of freedom, and idler gears are provided between the input side large gears and the input gears of the left and right intermediate gear shafts and between the output side small gears and the output gears of the left and right intermediate gear shafts, respectively. The distance from the center of the rotor shaft of the electric motor to the gear device is made larger than the distance from the center of the rotor shaft of the electric motor to the radial end of the stator of the electric motor. A part of the gear device is overlapped with the outer diameter surface of the electric motor.

  The gear device has a configuration in which two planetary gear mechanisms having three elements and two degrees of freedom are connected, and the planetary gear mechanism includes an internal gear, a planet carrier provided coaxially with the internal gear, A first coupling member having a sun gear provided coaxially with an internal gear and a plurality of planetary gears as revolving gears, and coupling one planet carrier and the other one element of the two planetary gear mechanisms. And a second coupling member that couples one of the same one element and the other planetary carrier, and the input element of the gear device is coaxial with the input-side large-diameter gear of the intermediate gear shaft of the reduction gear. The output side small-diameter gear of the intermediate gear shaft is connected to the output element of the gear device.

  In addition, the speed reducer is arranged on the inboard side of the vehicle with a gear train composed of an output side small diameter gear and an output gear of the intermediate gear shaft with respect to a gear train composed of an input gear and an input side large diameter gear of the intermediate gear shaft. It was made to be.

  The planetary gear mechanism is a single pinion planetary gear mechanism, and includes a first coupling member that couples one planet carrier of the two planetary gear mechanisms and the other sun gear, one sun gear, and the other planetary gear. A second coupling member coupled to the carrier, the internal gear of the gear device is coaxially connected to the input-side large-diameter gear of the intermediate gear shaft of the reduction gear, and the output-side small-diameter gear of the intermediate gear shaft is It is connected coaxially with the planet carrier of the planetary gear mechanism.

  An axial direction in which an input-side large-diameter gear meshed with an input gear and an idler gear and an internal gear of the planetary gear mechanism are radially overlapped with an intermediate gear shaft of the speed reducer that is coaxial with the gear device. Placed in position.

  The planetary carrier of the planetary gear mechanism supports the planetary gear via a carrier pin and has carrier flanges extending on the inboard side and the outboard side of the vehicle, and the planetary carrier houses the speed reducer. It is rotatably supported by two rolling bearings with respect to the reduction gear housing.

  Further, an output side small-diameter gear of an intermediate gear shaft that meshes with the output gear may be provided coaxially on the inboard side of the planetary carrier vehicle.

  Further, the planetary gear mechanism can be configured such that the internal gear is rotatably supported by a rolling bearing with respect to the planet carrier.

  The speed reducer housing that houses the two speed reducers has a three-piece configuration including a central housing and left and right side housings, and a partition wall that partitions the left and right is provided at a central portion of the central housing. A coupling member and the second coupling member may be configured to penetrate the partition wall.

  The idler gear provided between the input gear of the reduction gear and the input-side large-diameter gear of the intermediate gear shaft is a rolling bearing with respect to a shaft fixed by brackets on motor side walls of the left and right side housings of the reduction gear housing. And can be configured to be held rotatably.

  The idler gear provided between the output side small gear and the output gear of the intermediate gear shaft of the reducer is a rolling bearing with respect to a shaft fixed by a bracket to the partition wall surface of the central housing of the reducer housing. It can be configured to be held rotatably.

  In the gear device, the first coupling member and the second coupling member are arranged coaxially, one coupling member is a hollow shaft, and the other coupling member is a shaft that is inserted into the hollow shaft. It has a heavy structure, and the connection between the first and second coupling members and the planet carrier to which the respective coupling members are coupled can be configured by spline fitting.

  Further, in the coupling member on the inner diameter side of the first and second coupling members, the shaft end opposite to the spline fitting portion with the planet carrier can be rotatably supported by the rolling bearing.

  The planetary gear mechanism is a single pinion planetary gear mechanism, and includes a first coupling member that couples one planet carrier and the other internal gear of the two planetary gear mechanisms, one internal gear, and the other planetary gear. A second coupling member coupled to the carrier, the sun gear of the gear device is coaxially coupled to the input-side large-diameter gear of the intermediate gear shaft of the reduction gear, and the output-side small-diameter gear of the intermediate gear shaft is It can be configured to be connected coaxially with the planet carrier of the planetary gear mechanism.

  The planetary gear mechanism includes an internal gear, a planet carrier provided coaxially with the internal gear, a sun gear provided coaxially with the internal gear, and a plurality of double planets as revolving gears. And when the planetary carrier is fixed, the internal gear rotates in the same direction as the sun gear, and the first planetary carrier of the two planetary gear mechanisms and the other internal gear are coupled to each other. A coupling member, and a second coupling member for coupling one internal gear and the other planetary carrier, and the sun gear of the gear device is coaxially coupled to the input large-diameter gear of the intermediate gear shaft of the reduction gear In addition, the output side small-diameter gear of the intermediate gear shaft can be configured to be coaxially connected to the planet carrier of the planetary gear mechanism.

  The planetary gear mechanism includes an internal gear, a planet carrier provided coaxially with the internal gear, a sun gear provided coaxially with the internal gear, and a plurality of double planets as revolving gears. And when the planet carrier is fixed, the internal gear rotates in the same direction as the sun gear, and couples one planet carrier and the other sun gear of the two planetary gear mechanisms. A coupling member, and a second coupling member that couples one sun gear and the other planet carrier, and the planetary carrier of the gear device is coaxially coupled to the input large-diameter gear of the intermediate gear shaft of the reduction gear In addition, the output side small-diameter gear of the intermediate gear shaft can be configured to be coaxially connected to the internal gear of the planetary gear mechanism.

  As described above, according to the present invention, idler gears are respectively provided between the input side large diameter gears of the left and right intermediate gear shafts and the input gear, and between the output side small diameter gears and the output gears of the left and right intermediate gear shafts. The distance from the center of the rotor shaft of the electric motor to the radial end of the stator of the electric motor is made larger than the distance from the center of the rotor shaft of the electric motor to the gear device, By overlapping a part of the provided gear device with the outer diameter surface of the electric motor, the dimension of the vehicle drive device mounting space in the vehicle width direction can be reduced, the vehicle width can be reduced, narrow alleys, etc. The vehicle is easy to handle, and the vehicle drive device is mounted on the steering wheel, so that the steering angle of the steering wheel can be increased, the vehicle can be turned easily, the structure and arrangement of the suspension system are less restricted, and the vehicle width Direction arm length Kutore, ride comfort and steering stability is obtained, the effect of good, or the like.

  Further, according to the present invention, the output gear shaft is coaxially provided inside the hollow rotor shaft, whereby the size in the direction perpendicular to the shaft of the reduction gear can be reduced and the vehicle drive device can be downsized. .

1 is a cross-sectional plan view showing an embodiment of a vehicle drive device according to the present invention. It is sectional drawing of the II-II line of FIG. It is the cross-sectional top view which expanded a part of FIG. It is sectional drawing of the IV-IV line of FIG. It is sectional drawing of the VV line of FIG. It is explanatory drawing which shows an example of the electric vehicle of the rear-wheel drive system which mounts the vehicle drive device which concerns on this invention, and has shown the gear structure with the skeleton figure. It is explanatory drawing which shows an example of the electric vehicle of the front-wheel drive system which mounts the vehicle drive device which concerns on this invention, and has shown the gear structure with the skeleton figure. It is explanatory drawing which shows an example of the electric vehicle of the four-wheel drive system which mounts the vehicle drive device which concerns on this invention, and has shown the gear structure with the skeleton figure. It is a speed diagram for demonstrating the torque difference amplification factor by the gear apparatus incorporated in the vehicle drive device which concerns on 1st Embodiment of this invention. It is a skeleton figure which shows the gear structure of the vehicle drive device of 2nd Embodiment of this invention. It is a velocity diagram for demonstrating the torque difference amplification factor by the gear apparatus integrated in the vehicle drive device of 2nd Embodiment of this invention. It is a skeleton figure which shows the gear structure of the vehicle drive device 1 of 3rd Embodiment of this invention. It is a speed diagram for demonstrating the torque difference amplification factor by the gear apparatus integrated in the vehicle drive device 1 of 3rd Embodiment of this invention. It is a skeleton figure which shows the gear structure of the vehicle drive device of 4th Embodiment of this invention. It is a speed diagram for demonstrating the torque difference amplification factor by the gear apparatus integrated in the vehicle drive device of 4th Embodiment of this invention. It is a cross-sectional top view which shows the vehicle drive device of a prior application example. It is the cross-sectional top view which expanded a part of FIG.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
As shown in FIG. 1, the two-motor type vehicle drive device 1 according to the present invention has a reduction gear housing 9 that accommodates two reduction gears 3 </ b> L and 3 </ b> R in parallel on the left and right sides. A structure is adopted in which the motor housings 4L and 4R of the two electric motors 2L and 2R are fixedly arranged on the outboard side of the vehicle.

  The electric vehicle AM according to the embodiment of the present invention shown in FIG. 6 is a rear wheel drive system, and includes a chassis 60, rear wheels 61L and 61R as drive wheels, front wheels 62L and 62R, and left and right rear wheels 61L and 61R. The two-motor type vehicle driving device 1 is mounted on the chassis 60 at the center position of the left and right rear wheels 61L and 61R. The driving force of the vehicle driving device 1 is as follows: It is transmitted to the left and right rear wheels 61L and 61R via the constant velocity joints 65a and 65b and the intermediate shaft 65c. In FIG. 6, the gear structure of the vehicle drive device 1 is shown in a skeleton diagram.

The torque (driving force) of the electric motors 2L, 2R is an input side large-diameter gear composed of the input gear 12a of the rotor shafts 12L, 12R serving as the input gear shaft of the reduction gears 3L, 3R and the external gears of the intermediate gear shafts 13L, 13R. 13a is increased by the gear ratio and transmitted to the internal gears R _L and R _R of the gear unit 30.

  An idler gear 70 is provided between the input gear 12a and the input-side large-diameter gear 13a. As shown in FIG. 1, the idler gear 70 described above has a distance (L1) from the center of the rotor shafts 12L, 12R of the electric motors 2L, 2R to the radial ends of the stator 6 of the electric motors 2L, 2R. The diameter of the idler gear 70 is defined such that the distance (L2) from the center of the rotor shafts 12L, 12R of the electric motors 2L, 2R to the gear device 30 is increased. And in order to shorten the dimension of the axial direction of the vehicle drive device 1, a part of gear apparatus 30 is made to overlap with the outer-diameter surface of electric motor 2L, 2R. Thus, by determining the diameter of the idler gear 70, the outer diameter surfaces of the electric motors 2L and 2R and the gear device 30 provided integrally with the speed reducers 3L and 3R do not overlap each other when viewed from the axial direction. Thus, a part of the gear device 30 can be overlapped with the outer diameter surfaces of the electric motors 2L and 2R, the useless space is compressed, and the axial dimension of the vehicle drive device 1 is reduced.

  As shown in FIG. 6, the output-side small-diameter gear 13 b composed of the external gears of the intermediate gear shafts 13 </ b> L and 13 </ b> R is connected via the gear device 30 to the large-diameter output gear 14 a of the output gear shafts 14 </ b> L and 14 </ b> R. And the torque of the electric motors 2L, 2R is further increased by the gear ratio between the output-side small-diameter gear 13b and the output gear 14a, and is output to the drive wheels 61L, 61R.

  The gear device 30 is configured by combining two planetary gear mechanisms 30L and 30R having the same three-element and two-degree-of-freedom with coaxial intermediate gear shafts 13L and 13R. The planetary gear mechanisms 30L and 30R are of a single pinion type. A planetary gear mechanism is used.

The planetary gear mechanisms 30L and 30R are coaxially provided with sun gears S _L and S _R and internal gears R _L and R _R, and between these sun gears S _L and S _R and the internal gears R _L and R _R. A plurality of planetary gears P _L , P _R located in the direction of the planetary gears, and planetary gears P _L , P _R rotatably supported by the planetary gears provided coaxially with the sun gears S _L , S _R and the internal gears R _L , R _R It is composed of carriers C _L and C _R. Here, the sun gears S _L and S _R and the planetary gears P _L and P _R are external gears having gear teeth on the outer periphery, and the internal gears R _L and R _R are internal gears having gear teeth on the inner periphery. The planetary gears P _L and P _R mesh with the sun gears S _L and S _R and the internal gears R _L and R _R.

This gear device 30 includes a first planetary gear mechanism 30L having a sun gear S _L , a planet carrier C _L , a planet gear P _L and an internal gear R _L , and the sun gear S _R , planet carrier C _R , and planet gear P P. The second planetary gear mechanism 30R having the _R and the internal gear R _R is coaxially combined. Here, the sun gears S _L and S _R and the planetary gears P _L and P _R are external gears having gear teeth on the outer periphery, and the internal gears R _L and R _R are internal gears having gear teeth on the inner periphery. The planetary gears P _L and P _R mesh with the sun gears S _L and S _R and the internal gears R _L and R _R.

Outputs from the electric motors 2L and 2R are given to the internal gears R _L and R _R of the two planetary gear mechanisms 30L and 30R, respectively, and outputs from the first coupling member 31 and the second coupling member 32 are output side small diameters. It is increased between the gear 13b and the output gear 14a and applied to the drive wheels 61L and 61R.

  In the rear wheel drive system, the gear device 30 that amplifies the torque difference may be on the vehicle body front side or the rear side with respect to the output gear shafts 14L and 14R.

  As a mounting form of the two-motor type vehicle drive device 1, in addition to the rear wheel drive method shown in FIG. 6, either the front wheel drive method shown in FIG. 7 or the four wheel drive method shown in FIG.

  The electric vehicle AM according to the embodiment shown in FIG. 7 is a front wheel drive system, and drives the chassis 60, the rear wheels 61L and 61R, the front wheels 62L and 62R as drive wheels, and the left and right front wheels 62L and 62R, respectively. The vehicle drive device 1 is mounted on the chassis 60 at the center position of the left and right front wheels 62L and 62R. The drive force of the vehicle drive device 1 is a constant velocity joint 65a, 65b and the intermediate shaft 65c are transmitted to the left and right front wheels 62L and 62R.

  In the front wheel drive system, the gear device 30 that amplifies the torque difference may be on the vehicle body front side or the rear side with respect to the output gear shafts 14L and 14R.

  The electric vehicle AM according to the embodiment shown in FIG. 8 is a four-wheel drive system, and includes a chassis 60, rear wheels 61L and 61R as drive wheels, front wheels 62L and 62R as drive wheels, and left and right rear wheels 61L. , 61R for driving the left and right front wheels 62L, 62R for driving the left and right rear wheels 61L. 61R and the left and right front wheels 62L and 62R are mounted on the chassis 60 at the center position thereof, and the driving force of the vehicle drive device 1 is applied to the left and right rear wheels 61L through the constant velocity joints 65a and 65b and the intermediate shaft 65c. 61R and the left and right front wheels 62L and 62R are transmitted.

  1 and 6 includes two electric motors 2L and 2R that are mounted on a vehicle and can be controlled independently, left and right driving wheels 61L and 61R, and two electric motors 2L, 2R left and right reduction gears 3L, 3R provided between 2R.

  As shown in FIG. 1, a speed reducer housing 9 that accommodates two speed reducers 3L and 3R provided in parallel on the left and right is a central housing 9a and left and right side housings 9bL fixed to both side surfaces of the central housing 9a. , 9bR three-piece structure.

  The left and right electric motors 2L and 2R in the vehicle drive device 1 according to the present invention are accommodated in motor housings 4L and 4R as shown in FIG.

  The motor housings 4L and 4R include cylindrical motor housing bodies 4aL and 4aR, and outer walls 4bL and 4bR that close the outer surfaces of the motor housing bodies 4aL and 4aR. An opening 40 through which the gear shafts 14L and 14R are drawn is provided. Further, the inner side surfaces of the motor housing bodies 4aL and 4aR on the side of the speed reducers 3L and 3R are closed by side surface housings 9bL and 9bR of the speed reducer housing 9.

  A cooling water channel 41 is disposed in the motor housing bodies 4aL and 4aR, and coolant is supplied to the water channel 41 from a radiator (not shown). The water channel 41 constitutes a so-called water jacket, thereby effectively cooling the electric motors 2L, 2R.

  As shown in FIG. 1, the electric motors 2 </ b> L and 2 </ b> R are of a radial gap type in which a stator 6 is provided on the inner peripheral surface of the motor housing body 4 aL and 4 aR, and a rotor 5 is provided on the inner periphery of the stator 6. I am using something.

  The rotor 5 has rotor shafts 12L and 12R at the center. The rotor shafts 12L and 12R function as input gear shafts. The rotor shafts 12L and 12R have a hollow structure penetrating in the axial direction, and end portions of the rotor shafts 12L and 12R on the inboard side of the vehicle pass through the side housings 9bL and 9bR of the speed reducer housing 9 to reduce the speed reducer housing. 9 is inserted. An input gear 12a is provided on the outer peripheral surface of the end of the rotor shafts 12L and 12R inserted into the reduction gear housing 9. The input gear 12a transmits torque to the input-side large-diameter gear 13a of the intermediate gear shafts 13L and 13R via the idler gear 70.

  As shown in FIG. 4, the idler gear 70 has a pair of deep groove balls on a shaft 73a supported by a hole provided in the side housings 9bL, 9bR of the reduction gear housing 9 and a bracket 75 attached to the side housings 9bL, 9bR by bolts 74. It is rotatably supported via rolling bearings 72a and 72a comprising bearings. The rolling bearings 72a and 72a that support the idler gear 70 are not limited to deep groove ball bearings, but may be any radial bearing such as a cylindrical roller bearing or a needle roller bearing.

  In the embodiment of FIG. 1, the input gear 12a is integrally formed on the outer peripheral surfaces of the end portions of the rotor shafts 12L and 12R. However, the input gear 12a is formed so as to be fitted to the rotor shafts 12L and 12R by a spline or the like. May be.

  The rotor shafts 12L, 12R are rotatably supported by the rolling bearings 10a, 10b on the outer walls 4bL, 4bR of the motor housings 4L, 4R and the side housings 9bL, 9bR of the reduction gear housing 9 (FIG. 1). .

  Output gear shafts 14L and 14R are coaxially arranged inside the hollow rotor shafts 12L and 12R.

  The output gear shafts 14 </ b> L and 14 </ b> R have a large-diameter output gear 14 a disposed in the vicinity of the partition wall 11 in the central housing 9 a on the inboard side of the vehicle in the speed reducer housing 9. The bearings 16a and 17b are rotatably supported by the bearing fitting holes 16a of the formed bosses and the openings 40 of the outer walls 4bL and 4bR of the motor housings 4L and 4R. The output gear 14a is splined to the output gear shafts 14L and 14R. The output gear 14a meshes with the output-side small gear 13b of the intermediate gear shafts 13L, 13R via the idler gear 71, and the torque of the electric motors 2L, 2R is generated at the gear ratio between the output-side small gear 13b and the output gear 14a. Further increased and output to the drive wheels 61L and 61R.

  As shown in FIG. 5, the idler gear 71 has a pair of deep groove balls on a shaft 73 b supported by a hole provided in the partition wall 11 of the central housing 9 a of the reduction gear housing 9 and a bracket 76 attached to the partition wall 11 by bolts 74. It is rotatably supported via rolling bearings 72b and 72b comprising bearings. The rolling bearings 72b and 72b for supporting the idler gear 71 are not limited to deep groove ball bearings, but may be any radial bearing such as a cylindrical roller bearing or a needle roller bearing.

  On the outboard side of the rolling bearing 17b that rotatably supports the output gear shafts 14L and 14R, a space between the output gear shafts 14L and 14R and the openings 40 of the outer walls 4bL and 4bR of the motor housings 4L and 4R is sealed. An oil seal 39 is provided.

  A shaft 650 to which an outer ring 651 of a constant velocity joint 65a is attached is spline-fitted to the wheel side ends of the output gear shafts 14L and 14R, and power is transmitted to the drive wheels 61L and 61R via the intermediate shaft 65c. The A trunnion, a roller, an intermediate shaft 65c, and the like are disposed inside the constant velocity joint 65a, and a boot 653 is fitted between the intermediate shaft 65c and the outer ring 651. It is not limited to the tripod type using the trunnion or roller shown in the figure, but may be a double offset type using a steel ball.

  The drive torque of the two-motor type vehicle drive device 1 is transmitted to the left and right drive wheels 61L and 61R via a drive shaft composed of constant velocity joints 65a and 65b and an intermediate shaft 65c (FIG. 6).

  The left and right electric motors 2L and 2R in the two-motor type vehicle drive device 1 use electric motors having the same output characteristics, and are housed in motor housings 4L and 4R as shown in FIG. As shown in FIG. 2, which is a cross-section taken along line II-II in FIG. 1, output gear shafts 14L and 14R are coaxially arranged inside the rotor shafts 12L and 12R serving as input gear shafts, and the rotor shaft 12L, 12R and the intermediate gear shafts 13L and 13R are arranged offset from each other.

  The first rotor shafts 12L, 12R of the reduction gears 3L, 3R and the third output gear shafts 14L, 14R are arranged coaxially and are disposed through the rotor shafts 12L, 12R. By arranging the idler gears 70 and 71, the dimension in the direction perpendicular to the axis (radial direction) of the vehicle drive device 1 is increased, but the second intermediate gear shafts 13L and 13R are compared with the first and third axes. Since it is arranged in an offset manner, the size in the direction perpendicular to the axial direction is smaller than that arranged in an offset manner from one to three axes, and the dimension in the direction perpendicular to the axial direction can be increased. It can be reduced as much as possible. Furthermore, since the outer diameter surfaces of the electric motors 2L and 2R and the gear device 30 are disposed so as to overlap, the axial dimension of the vehicle drive device 1 can be reduced.

  A reduction gear housing 9 that accommodates two reduction gears 3L and 3R provided in parallel on the left and right is divided into three pieces in a direction orthogonal to the gear shafts of the reduction gears 3L and 3R, as shown in FIG. The housing 9a has a three-piece structure including left and right side housings 9bL and 9bR fixed to both side surfaces of the central housing 9a. The left and right side housings 9bL and 9bR are fixed to the openings on both sides of the central housing 9a by a plurality of bolts (not shown).

  As shown in FIG. 1, the central housing 9a is provided with a partition wall 11 at the center. The speed reducer housing 9 is divided into left and right parts by the partition wall 11, and left and right accommodation chambers for accommodating the two speed reducers 3L and 3R are provided in parallel.

  As shown in FIG. 1, the speed reducers 3L and 3R are provided substantially symmetrically, and torque is transmitted from rotor shafts 12L and 12R serving as input gear shafts, and input gears 12a provided on the rotor shafts 12L and 12R. Intermediate gear shafts 13L and 13R having a large-diameter input-side large-diameter gear 13a to which torque is transmitted and an output-side small-diameter gear 13b meshing with the output gear 14a, and an output gear 14a, and the rotor shafts 12L and 12R This is a parallel shaft gear reducer including output gear shafts 14L and 14R arranged coaxially inside. Output gear shafts 14L, 14R coaxially arranged inside the rotor shafts 12L, 12R are pulled out of the motor housings 4L, 4R and driven wheels 61L via constant velocity joints 65a, 65b and an intermediate shaft 65c (FIG. 4). , 61R to transmit torque.

  The input side large gear 13a provided on the input gear 12a and the intermediate gear shafts 13L and 13R meshes via an idler gear 70, and transmits the torque of the input gear 12a to the input side large gear 13a.

  The intermediate gear shafts 13 </ b> L and 13 </ b> R have a gear shaft assembly having an input-side large-diameter gear 13 a meshed with the input gear 12 a via an idler gear 70 and an output-side small-diameter gear 13 b meshed with the output gear 14 a via an idler gear 71. Is configured. Both ends of the intermediate gear shafts 13L and 13R are inserted into bearing fitting holes 19a formed on both surfaces of the partition wall 11 of the central housing 9a and bearing fitting holes 19b formed on the side housings 9bL and 9bR via rolling bearings 20a and 20b. It is supported. And the bearing fitting hole 19a has penetrated so that the 1st coupling member 31 mentioned later and the 2nd coupling member 32 may pass.

  The intermediate gear shafts 13L and 13R arranged on the same axis have a torque difference between the left and right drive wheels 61L and 61R on the same axis as the intermediate gear shafts 13L and 13R. A gear device 30 for amplifying and distributing is incorporated. The gear device 30 is composed of a planetary gear mechanism having three elements and two degrees of freedom, which are combined on the same axis.

  As described above, the idler gears 70 and 71 are arranged so that the gear device 30 that is a torque difference amplification mechanism and the outer diameter surfaces of the electric motors 2L and 2R overlap. For this reason, the electric motors 2L and 2R can be arranged closer to the inboard side of the vehicle than the distance between the rolling bearing 20b of the intermediate gear shaft 13L and the rolling bearing 20b of the intermediate gear shaft 13R. As a result, the axial length can be made shorter than that of the vehicle drive device of the prior application example shown in FIG.

As shown in the enlarged view of FIG. 3, the gear device 30 includes internal gears R _L and R _R coupled to large-diameter input-side large gears 13 a of the intermediate gear shafts 13 L and 13 _R , an internal gear R _L , R _R and the sun gear S _L provided coaxially, S _R and internal gear R _L, R _R and the sun gear S _L, the planetary gear P _L as a revolving gear meshing with S _R, and P _R, the planetary gears P _L, is connected to the P _R, the internal gear R _L, R _R and the sun gear S _L, S _R and the planetary carrier provided coaxially C _L, the planetary gear mechanism consisting of a C _R 30L, and 30R, whereas Of the first planetary carrier C _L (left side of the figure in FIG. 3) and the other sun gear S _R (right side of the figure in FIG. 3) and one sun gear S _L (shown in FIG. 3) on the left) and the second coupling member 32 for coupling the other of the planet carrier C _R (in FIG. in FIG. 3 the right) and the input gear 12a in mesh The intermediate gear shafts 13L and 13R have input side large-diameter gears 13a, and the output gear shafts 14L and 14R output gears 14a mesh with the intermediate gear shafts 13L and 13R. The output side small-diameter gear 13b of 13R is connected to the planetary carriers C _L and C _R.

In the embodiment shown in FIGS. 1 and 3, the internal gear R _L, the input side is connected to R _R large diameter gear 13a is an internal gear R _L, and is formed integrally with the R _R. By arranging the input-side large-diameter gear 13a and the internal gears R _L and R _R at axial positions that overlap each other in the radial direction, it is possible to reduce the axial dimension compared to arranging them side by side in the axial direction.

Planet carrier C _L, C _R is the planetary gears P _L, a carrier pin 33 which supports the P _R, and the carrier flange 34a on the outboard side which is connected to the outboard side end portion of the carrier pin 33, inboard end And an inboard carrier flange 34b connected to the portion.

  The carrier flange 34a on the outboard side includes a hollow shaft portion 35 extending toward the outboard side, and the end portion on the outboard side of the hollow shaft portion 35 is formed on the side housings 9bL and 9bR of the reduction gear housing 9. The fitting hole 19b is supported via a rolling bearing 20b.

  The carrier flange 34b on the inboard side includes a hollow shaft portion 36 extending toward the inboard side, and an end portion on the inboard side of the hollow shaft portion 36 is formed in a bearing fitting hole formed in the partition wall 11 of the central housing 9a. 19a is supported via a rolling bearing 20a. In the embodiment shown in FIGS. 1 and 3, the hollow shaft portion 36 of the intermediate gear shaft 13 </ b> R is spline-fitted with the second coupling member 32.

  In the embodiment shown in FIGS. 1 and 3, the output-side small-diameter gear 13b is spline-fitted to the outer peripheral surface of the hollow shaft portion 36 of the carrier flange 34b.

The planetary gears P _L and P _R are supported by the carrier pin 33 via the needle roller bearing 37.

Wherein each carrier flange 34a, 34b outer peripheral surface and the inner gear R _L of the, between the R _R, the rolling bearing 38a, are disposed 38b. By being supported by the rolling bearings 38a and 38b, the internal gears R _L and R _R and the input-side large-diameter gear 13a connected thereto can be rotated with high accuracy.

  The first coupling member 31 and the second coupling member 32 that couple the two planetary gear mechanisms that constitute the gear device 30 of the vehicle drive device 1 define the partition wall 11 that partitions the central housing 9a of the speed reducer housing 9 to the left and right. It is built through.

  The first coupling member 31 and the second coupling member 32 are arranged coaxially, and one coupling member (the second coupling member 32 in the embodiment of FIGS. 1 and 3) is a hollow shaft, and the other coupling member. (In the embodiment of FIGS. 1 and 3, the first coupling member 31) has a double structure including a shaft inserted through the hollow shaft.

In the embodiment shown in FIGS. 1 and 3, an end portion of the right side of the planetary gear mechanism 30R side of the second coupling member 32 consists of a hollow shaft, the hollow shaft of the carrier flange 34b on the inboard side of the planet carrier C _R The portion 36 is spline-fitted, but may be integrally formed.

Further, in the embodiment shown in FIGS. 1 and 3, an end portion of the left planetary gear mechanism 30L side of the first coupling member 31, to the hollow shaft portion 35 of the carrier flange 34a on the outboard side of the planet carrier C _L the splines are provided, they are connected by spline fitting to the first coupling member 31 the planet carrier C _L.

End of the planetary gear mechanism 30L side of the second coupling member 32 has, on its outer peripheral surface, the external gear is formed to mesh with the planetary gears P _L of the planetary gear mechanism 30L, the sun gear S of the outer gear planetary gear mechanism 30L _L is composed.

The first coupling member 31 inserted through the second coupling member 32 constituted by a hollow shaft has a large-diameter portion 43 at an end portion on the planetary gear mechanism 30R side. external gear meshing with the planetary gears P _R of the gear mechanism 30R is formed, the outer gear constitutes the sun gear S _R of the planetary gear mechanism 30R.

The coupling member (the first coupling member 31 in the embodiment of FIGS. 1 and 3) on the inner diameter side of the double-structure shaft that couples the two planetary gear mechanisms is the coupling member (the first coupling member 31 in the embodiment of FIGS. 1 and 3). 1 coupling member 31) and the planet carrier (C _{L in the} embodiment of FIGS. 1 and 3), the shaft end opposite to the spline fitting, and the other planet carrier (C _{R in the} embodiment of FIGS. 1 and 3) ) Is supported by a deep groove ball bearing 49.

  As shown in FIGS. 1 and 3, the output gear shafts 14L and 14R are coaxially arranged inside the hollow rotor shafts 12L and 12R. A needle roller bearing 48 is provided between the inner peripheral surface of the inboard side ends of the rotor shafts 12L and 12R and the outer peripheral surface of the output gear shafts 14L and 14R at an axial position that also serves as the inner peripheral surface of the input gear 12a. The input gear 12a supports the radial load received by meshing with the input-side large-diameter gear 13a. The needle roller bearing 48 prevents the inboard side ends of the rotor shafts 12L and 12R from becoming cantilever beams, prevents deflection due to a radial load, and allows the input gear 12a to rotate with high accuracy. A shaft 650 to which an outer ring 651 of a constant velocity joint 65a is attached is spline-fitted to the inner peripheral surface of the end portion on the outboard side of the output gear shafts 14L, 14R.

  The constant velocity joint 65a coupled to the output gear shafts 14L and 14R is connected to the drive wheels 61L and 61R via the intermediate shaft 65c and the constant velocity joint 65b (FIG. 6).

  As shown in FIG. 1, an oil seal 39 is provided between the end of the output gear shafts 14L and 14R on the outboard side and the opening 40 formed in the side housings 9bL and 9bR. This prevents leakage of used lubricant and intrusion of muddy water from the outside.

Each of the input side large-diameter gears 13a is a planetary gear train of sun gears S _L , S _R , planetary gears P _L , P _R , internal gears R _L , R _R of the planetary gear mechanism 30L and the planetary gear mechanism 30R. It is arranged at a position (inboard side) sandwiched in the axial direction. With this configuration, the idler gear 70 that transmits torque to the input-side large-diameter gear 13a and the input gear 12a can be arranged close to the inboard side of the vehicle of the vehicle drive device 1, and two electric motors can be arranged. The motors 2L and 2R can be arranged close to the axial direction. For this reason, the axial direction dimension of the vehicle drive device 1 can be reduced.

  The gears constituting the reduction gears 3L and 3R in the reduction gear housing 9 are all external gears, and the gears and bearings in the reduction gear housing 9 are lubricated in the lower part of the internal space of the reduction gear housing 9. This is done by the oil being swirled by the gears.

  On the other hand, if the lubricating oil that has entered the motor housings 4L and 4R is not sufficiently discharged, the oil level inside the motor housings 4L and 4R increases, and the oil stirring loss due to the rotor 5 increases. For this reason, the following structure is adopted in order to properly discharge the lubricating oil inside the motor housings 4L and 4R to the reduction gear housing 20 side.

  As shown in FIG. 1, the interiors of the motor housings 4 </ b> L and 4 </ b> R are divided into two spaces 4 c and 4 d in the axial direction by the stator 6 and the rotor 5.

  An oil passage communicating the two spaces 4c and 4d is provided in the vicinity of the lowermost portion (bottom dead center) of the stator 6. For example, axial grooves (not shown) are provided on the outer periphery of the stator 6 or the inner peripheral portions of the motor housings 4L and 4R as oil passages that communicate the spaces 4c and 4d.

  Further, a through oil passage 90 is provided in the side housings 9bL and 9bR that partition the motor housings 4L and 4R and the reduction gear housing 9. As shown in FIG. 2, the through oil passage 90 is provided at a lower position in the lowermost part of the reduction gear housing 9.

  An axial groove is provided as an oil passage that communicates the spaces 4c and 4d, and the through oil passage 90 is provided at a position lower than the lowest part (bottom dead center) of the rotor 5, so that it is provided at the end in the wheel side direction. Lubricating oil supplied to the bearings 10b and 17b and the oil seal 39 through the inside of the output gear shafts 14L and 14R moves from the space 4c of the motor housings 4L and 4R to the space 4d and is not lifted up by the rotor 5 , Returned to the reducer housing 9.

  The gear configuration of the two-motor vehicle drive device 1 of the embodiment shown in FIG. 1 is as shown in the skeleton diagram of FIG.

  As shown in FIG. 6, the left and right electric motors 2 </ b> L and 2 </ b> R are operated by electric power supplied from a battery 63 mounted on the vehicle via an inverter 64. The electric motors 2L and 2R are individually controlled by an electronic control device (not shown), and can generate and output different torques.

The torques of the rotor shafts 12L, 12R of the electric motors 2L, 2R are external gears of the intermediate gear shafts 13L, 13R via the input gear 12a of the rotor shafts 12L, 12R serving as the input gear shafts of the speed reducers 3L, 3R and the idler gear 70. Is transmitted to the internal gears R _L and R _R of the gear unit 30 after being increased in the gear ratio of the input gear 12a and the input large gear 13a.

  Then, the output side small gear 13b of the intermediate gear shafts 13L and 13R is engaged with the large diameter output gear 14a of the output gear shafts 14L and 14R via the idler gear 71 via the gear device 30, and the output side small gear 13b and the output are output. The torque of the rotor shafts 12L and 12R of the electric motors 2L and 2R is further increased by the gear ratio with the gear 14a and is output to the drive wheels 61L and 61R.

As described above, the gear device 30 includes the first planetary gear mechanism 30L having the sun gear S _L , the planet carrier C _L , the planetary gear P _L, and the internal gear _RL , the sun gear S _R , and the planet carrier C _R. a second planetary gear mechanism 30R having a planetary gear P _R and the internal gear R _R is configured by combining coaxially.

Then, the planet carrier C _L of the first planetary gear mechanism 30L is binding and the sun gear S _R of the second planetary gear mechanism 30R to form a first coupling member 31, the sun gear S _L of the first planetary gear mechanism 30L When the planet carrier C _R of the second planetary gear mechanism 30R form a second coupling member 32 are coupled.

  The torque TM1 generated by the electric motor 2L is transmitted to the intermediate gear shaft 13L through the input gear 12a of the rotor shaft 12L serving as the input gear shaft and the input side large gear 13a through the idler gear 70, and is transmitted to the intermediate gear shaft 13L. The torque transmitted to 13L is transmitted to the output-side small gear 13b of the intermediate gear shaft 13L via the first planetary gear mechanism 30L, and the output-side small gear 13b of the intermediate gear shaft 13L is output to the output gear shaft via the idler gear 71. The 14L output gear 14a meshes, and the drive torque TL is output from the output gear shaft 14L to the drive wheel 61L.

  The torque TM2 generated by the electric motor 2R is transmitted to the intermediate gear shaft 13R through meshing engagement between the input gear 12a of the rotor shaft 12R serving as the input gear shaft, the idler gear 70, and the input large-diameter gear 13a, and is transmitted to the intermediate gear shaft 13R. The transmitted torque is transmitted to the output side small gear 13b of the intermediate gear shaft 13R via the second planetary gear mechanism 30R, and the output side small gear 13b of the intermediate gear shaft 13R is output to the output gear shaft 14R via the idler gear 71. 14a meshes with the output gear shaft 14R, and the drive torque TR is output to the drive wheel 61R.

Torques from the electric motors 2L and 2R are applied to the internal gears R _L and R _R of the two planetary gear mechanisms, and outputs from the first coupling member 31 and the second coupling member 32 are applied to the drive wheels 61L and 61R. Given.

  The 2nd coupling member 32 is comprised by the hollow shaft, the 1st coupling member 31 is penetrated in the inside, and the axis | shaft which comprises the 1st coupling member 31 and the 2nd coupling member 32 has a double structure. .

The first coupling member 31 has one end a rotation shaft of the (right end in the drawing) is the sun gear S _R, the other end (left end in the drawing) are provided through the sun gear S _L, connected to the planet carrier C _L Has been. The second coupling member 32 is a hollow shaft, one end (left end in the drawing) has a rotation shaft of the sun gear S _L, the other end (right end in the drawing) is connected to the planet carrier C _R. Two planetary gear mechanisms are coupled by the first coupling member 31 and the second coupling member 32.

Incidentally, the gear device 30 is configured by combining two identical single pinion planetary gear mechanisms 30L and 30R, and therefore can be represented by two velocity diagrams as shown in FIG. In the single pinion planetary gear mechanism, when the planetary carriers C _L and C _R are fixed, the sun gears S _L and S _R and the internal gears R _L and R _R rotate in opposite directions. , The internal gears R _L , R _R and the sun gears S _L , S _R are arranged on the opposite side to the planet carriers C _L , C _R.

Here, for easy understanding, the two speed diagrams are shifted up and down, the speed diagram of the left planetary gear mechanism 30L is shown on the upper side, and the speed diagram of the right planetary gear mechanism 30R is shown on the lower side. Originally, the torques TM1 and TM2 output from the electric motors 2L and 2R are respectively transmitted to the internal gears R _L , via the input-side large-diameter gears 13a meshing with the input gears 12a of the rotor shafts 12L and 12R and the idler gears 70. A reduction ratio is applied because it is input to _RR , and the drive torques TL and TR taken out from the gear unit 30 are output to the left and right drive wheels 61L and 61R via the output gear 14a meshing with the output-side small-diameter gear 13b and the idler gear 71. However, in order to facilitate understanding, the speed ratio and the calculation formulas shown in FIG. 9 are omitted in the description of the speed diagrams and the calculation formulas, and the internal gears R _L and R _R are omitted. The torque input to is kept at TM1 and TM2, and the drive torque is kept at TL and TR.

Since the two planetary gear mechanisms 30L and 30R constituting the gear device 30 use gear elements having the same number of teeth, the distance between the internal gear R _L and the planet carrier C _L and the internal gear in the speed diagram. The distance between R _R and the planet carrier C _R is equal, and this is a. Further, the distance between the sun gear S _L and the planet carrier C _L and the distance between the sun gear S _R and the planet carrier C _R are also equal, which is b. The ratio of the length from the planet carrier C _L , C _R to the internal gear R _L , R _R and the length from the planet carrier C _L , C _R to the sun gear S _L , S _R is the ratio of the internal gear R _L , R _R It is equal to the ratio of the reciprocal number (1 / Zr) of the number of teeth Zr and the reciprocal number (1 / Zs) of the number of teeth Zs of the sun gears S _L and S _R. Therefore, a = (1 / Zr) and b = (1 / Zs).

The following equation (1) is calculated from the balance of moment M with reference to the point of R _R. In FIG. 9, the arrow direction is the positive direction of the moment M.
a * TR + (a + b) * TL- (b + 2a) * TM1 = 0 (1)

The following equation (2) is calculated from the balance of moment M with reference to point R _L.
-A.TL- (a + b) .TR + (b + 2a) .TM2 = 0 (2)

The following formula (3) is obtained from the formula (1) + formula (2).
-B. (TR-TL) + (2a + b). (TM2-TM1) = 0
(TR-TL) = ((2a + b) / b). (TM2-TM1) (3)

  (2a + b) / b in the equation (3) is the torque difference amplification factor α. When a = 1 / Zr and b = 1 / Zs are substituted, α = (Zr + 2Zs) / Zr, and the following torque difference amplification factor α is obtained.

  α = (Zr + 2Zs) / Zr

In the first embodiment of the present invention, the inputs from the electric motors 2L and 2R are the internal gears R _L and R _R , and the outputs to the drive wheels 61L and 61R are the sun gear S _R , the planetary carrier C _L , and the planetary carrier. _CR and sun gear S _L.

  Then, when different torques TM1 and TM2 are generated by the two electric motors 2L and 2R to give the input torque difference ΔTIN (= (TM2−TM1)), the input torque difference ΔTIN is amplified in the gear device 30, and the input torque difference A driving torque difference α · ΔTIN larger than ΔTIN can be obtained. That is, even if the input torque difference ΔTIN is small, the input torque difference ΔTIN can be amplified by the above-described torque difference amplification factor α (= (Zr + 2Zs) / Zr) in the gear device 30, and the left drive wheel 61L and the right drive wheel A driving torque difference ΔTOUT (= α · (TM2−TM1)) larger than the input torque difference ΔTIN can be given to the driving torques TL and TR transmitted to 61R.

In the first embodiment of the present invention, the connection between the two planetary gear mechanisms constituting the gear device 30 that is the torque difference distribution mechanism is the sun gear S _L and the planet carrier C _R , and the sun gear S _R and the planet carrier C _L. Therefore, a connecting member having a larger diameter than the internal gears R _L and R _R is not required. Therefore, the vehicle drive device 1 for an electric vehicle incorporating the torque difference distribution mechanism can be reduced in size and weight.

  In the first embodiment of the present invention, the first rotor shafts 12L, 12R of the reduction gears 3L, 3R and the third output gear shafts 14L, 14R are coaxially arranged, and the interior of the rotor shafts 12L, 12R It is arranged to pass through. By arranging the idler gears 70 and 71, the diameter of the vehicle drive device 1 is increased, but the second intermediate gear shafts 13L and 13R are offset from the first and third shafts. Therefore, the size in the direction perpendicular to the axial direction (radial direction) is smaller than that arranged by offsetting from one axis to three axes, and the increase in dimension in the direction perpendicular to the axial direction can be reduced as much as possible. it can. Furthermore, since the electric motors 2L, 2R and the gear device 30 are arranged so as not to overlap each other when viewed from the axial direction, the dimension in the axial direction of the vehicle drive device 1 can be reduced. Thus, the vehicle drive device 1 can be downsized and the passenger compartment space can be increased.

  Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 10 is a skeleton diagram showing the gear configuration of the vehicle drive apparatus 1 according to the second embodiment of the present invention. FIG. 11 shows the torque difference amplification by the gear apparatus incorporated in the vehicle drive apparatus 1 according to the second embodiment of the present invention. It is a velocity diagram for demonstrating a rate.

  As shown in FIG. 10, the vehicle drive device 1 includes an electric motor 2L and an electric motor 2R mounted on the vehicle, a left drive wheel and a right drive wheel (not shown), and a gear device 30 provided therebetween. Reducers 3L and 3R are provided.

  An idler gear 70 is provided between the input gear 12a provided on the rotor shafts 12L and 12R of the electric motors 2L and 2R and the input-side large gear 13a provided on the intermediate gear shafts 13L and 13R, and the intermediate gear shaft 13L. , 13R, an idler gear 71 is provided between the output side small gear 13b provided on the output gear shaft 14L and the output gear 14a provided on the output gear shafts 14L, 14R. From the distance from the center of the rotor shafts 12L, 12R of the electric motors 2L, 2R to the radial ends of the stators 6 of the electric motors 2L, 2R by the idler gears 70, 71, the rotor shafts 12L of the electric motors 2L, 2R, The distance from the center of 12R to the gear device 30 is increased, and the outer diameter surfaces of the electric motors 2L and 2R and the gear device 30 provided integrally with the speed reducers 3L and 3R are arranged to overlap each other. The useless space is compressed and the axial dimension of the vehicle drive device 1 is reduced.

  The electric motor 2L and the electric motor 2R operate with electric power from a battery (not shown) mounted on the vehicle, are individually controlled by an electronic control device (not shown), and can generate and output different torques. . The driving force of the vehicle drive device 1 is transmitted to left and right drive wheels (not shown) via a constant velocity joint 65a and a drive shaft (not shown).

The torque of the electric motors 2L and 2R is such that the input gear 12a of the rotor shafts 12L and 12R serving as the input gear shafts of the speed reducers 3L and 3R, the idler gear 70, and the large input side large gear 13a of the intermediate gear shafts 13L and 13R. Is transmitted to the sun gears S _L and S _R of the gear unit 30.

  Then, the output side small gear 13b of the intermediate gear shafts 13L and 13R is engaged with the large diameter output gear 14a of the output gear shafts 14L and 14R via the idler gear 71 through the gear device 30, and the output side small gear 13b and the output gear are engaged. The torques of the electric motors 2L and 2R are further increased at a gear ratio with 14a and output to the drive wheels.

  The rotor shafts 12L and 12R have a hollow structure penetrating in the axial direction, and an input gear 12a is provided at the inboard side ends of the rotor shafts 12L and 12R. Output gear shafts 14L and 14R are coaxially arranged inside the hollow rotor shafts 12L and 12R.

  The gear device 30 is configured by combining two planetary gear mechanisms 30L and 30R having the same three-element and two-degree-of-freedom with coaxial intermediate gear shafts 13L and 13R. The planetary gear mechanisms 30L and 30R are of a single pinion type. A planetary gear mechanism is used.

Then, the planet carrier C _L of the first planetary gear mechanism 30L and the internal gear R _R of the second planetary gear mechanism 30R is coupled by a first coupling member 31, and the internal gear R _L of the first planetary gear mechanism 30L second a planet carrier C _R of the planetary gear mechanism 30R is coupled by the second coupling member 32.

Input is increased by the gear ratio between the torque TM1 generated by the electric motor 2L is input gear 12a and the idler gear 70 and the intermediate gear shaft input side large diameter gear 13a of 13L to the sun gear S _L of the first planetary gear mechanism 30L The torque TM2 generated by the electric motor 2R is increased by the gear ratio of the input gear 12a, the idler gear 70, and the input-side large-diameter gear 13a of the intermediate gear shaft 13R to increase the sun gear S _{R of} the second planetary gear mechanism 30R. Is input.

  The first coupling member 31 and the second coupling member 32 are provided with an output-side small-diameter gear 13b, and the output-side small-diameter gear 13b, the idler gear 71, and the large-diameter output gear 14a of the output gear shafts 14L and 14R mesh with each other. The constant velocity joint 65a is connected to the left and right drive wheels via the drive shaft, and the output is taken out.

In the second embodiment, the input from the electric motors 2L and 2R is the sun gears S _L and S _R , and the output to the drive wheels is the planet carrier C _L and the internal gear R _R and the planet carrier C _R and the internal It becomes gear _RL .

  Here, the drive torque transmitted by the gear device 30 according to the second embodiment will be described with reference to the velocity diagram shown in FIG.

Since the gear device 30 shown in FIG. 10 is configured by combining two identical single pinion planetary gear mechanisms 30L and 30R, the gear device 30 can be represented by two velocity diagrams as shown in FIG. Here, for ease of understanding, the two speed diagrams are shifted up and down, the speed diagram of the first planetary gear mechanism 30L is shown on the upper side, and the speed diagram of the second planetary gear mechanism 30R is shown on the lower side. Is shown. Similarly to the description in the first embodiment, in the following explanation of the velocity diagram and each calculation formula, the reduction ratios in the reduction gears 3L and 3R are omitted, and the sun gears S _L and S _R are omitted. The torque input to is kept TM1 and TM2.

In the gear device 30 shown in FIG. 10, the planet carrier C _L and the internal gear R _R, as shown by broken line in the drawing of FIG. 11, are coupled by a first coupling member 31, planet carrier C _R and the internal gear R _L is These are coupled by the second coupling member 32 as indicated by a broken line in the figure.

The torques TM1 and TM2 output from the electric motor 2L and the electric motor 2R are input to the sun gears S _L and S _R , respectively. On the other hand, driving torques TL and TR transmitted from the first coupling member 31 and the second coupling member 32 located in the middle on the velocity diagram to the left and right driving wheels are output.

  Also with the gear device 30 configured in this manner, the left drive is achieved by giving a torque difference (input torque difference) ΔTIN (= TM2−TM1) to the motor torques TM1 and TM2 generated by the electric motor 2L and the electric motor 2R. A drive torque difference ΔTOUT (= TR−TL) can be generated between the drive torque TL transmitted to the wheel and the drive torque TR transmitted to the right drive wheel.

The torque difference amplification factor α of the gear device 30 according to the second embodiment will be described. Also in the second embodiment, the two single pinion type planetary gear mechanisms 30L and 30R use gear elements having the same number of teeth, and therefore in the velocity diagram, the internal gear _RL and the planet carrier C The distance from _L and the distance between the internal gear R _R and the planet carrier C _R are equal, and this is a. Further, the distance between the sun gear S _L and the planet carrier C _L and the distance between the sun gear S _R and the planet carrier C _R are also equal, which is b. The ratio of the length from the planet carrier C _L , C _R to the internal gear R _L , R _R and the length from the planet carrier C _L , C _R to the sun gear S _L , S _R is the ratio of the internal gear R _L , R _R It is equal to the ratio of the reciprocal number (1 / Zr) of the number of teeth Zr and the reciprocal number (1 / Zs) of the number of teeth Zs of the sun gears S _L and S _R. Therefore, a = (1 / Zr) and b = (1 / Zs).

  In the velocity diagram of FIG. 11, when considering the balance of torque, the torque difference amplification factor α can be obtained. In FIG. 11, the arrow direction indicates the positive direction of the moment M.

The following equation (4) is calculated from the balance of the moment M with respect to the point of S _R.
b.TR + (a + b) .TL- (a + 2b) .TM1 = 0 (4)

Following formula (5) is calculated from the balance of moment M relative to the points S _L.
-B.TL- (a + b) .TR + (a + 2b) .TM2 = 0 (5)

The following equation (6) is calculated from the equation (4) + the equation (5).
a. (TR-TL)-(a + 2b). (TM2-TM1) = 0
(TR-TL) = ((a + 2b) / a). (TM2-TM1) (6)

  (A + 2b) / a in the equation (6) is the torque difference amplification factor α.

  When a = 1 / Zr and b = 1 / Zs are substituted, α = (2Zr + Zs) / Zs.

In this second embodiment, the electric motor 2L, input from 2R is the sun gear S _L, S _R, the output to the driving wheels planet carrier C _L and the internal gear R _R, a planet carrier C _R and the internal gear R _L , and the torque difference amplification factor α is (2Zr + Zs) / Zs.

  As described above, when different torques TM1 and TM2 are generated by the two electric motors 2L and 2R to give the input torque difference ΔTIN, the torque distribution gear device 30 amplifies the input torque difference ΔTIN, which is greater than the input torque difference ΔTIN. A large driving torque difference ΔTOUT (= α · (TM2−TM1)) can be obtained.

  Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 12 is a skeleton diagram showing a gear configuration of a vehicle drive device 1 according to a third embodiment of the present invention. FIG. 13 is a torque difference amplification by a gear device incorporated in the vehicle drive device 1 according to the third embodiment of the present invention. It is a velocity diagram for demonstrating a rate.

  As shown in FIG. 12, the vehicle drive device 1 includes an electric motor 2L and an electric motor 2R mounted on the vehicle, a left drive wheel and a right drive wheel (not shown), and a gear device 30 provided therebetween. Reducers 3L and 3R are provided.

  An idler gear 70 is provided between the input gear 12a provided on the rotor shafts 12L and 12R of the electric motors 2L and 2R and the input-side large-diameter gear 13a provided on the intermediate gear shafts 13L and 13R, and the intermediate gear shaft 13L, An idler gear 71 is provided between the output side small gear 13b provided on 13R and the output gear 14a provided on the output gear shafts 14L and 14R. From the distance from the center of the rotor shafts 12L, 12R of the electric motors 2L, 2R to the radial ends of the stators 6 of the electric motors 2L, 2R by the idler gears 70, 71, the rotor shafts 12L of the electric motors 2L, 2R, The distance from the center of 12R to the gear device 30 is increased, and the outer diameter surfaces of the electric motors 2L and 2R and the gear device 30 provided integrally with the speed reducers 3L and 3R are arranged to overlap each other. The useless space is compressed and the axial dimension of the vehicle drive device 1 is reduced.

  The electric motor 2L and the electric motor 2R operate by electric power from a battery (not shown) mounted on the vehicle, are individually controlled by an electronic control device (not shown), and can generate and output different torques. . The driving force of the vehicle drive device 1 is transmitted to left and right drive wheels (not shown) via a drive shaft (not shown) including a constant velocity joint 65a.

The torque of the electric motors 2L and 2R is transmitted from the input gear 12a of the rotor shafts 12L and 12R serving as the input gear shafts of the reduction gears 3L and 3R to the input side large gear 13a of the intermediate gear shafts 13L and 13R via the idler gear 70. Then, it is increased by the gear ratio between the input gear 12a and the input-side large-diameter gear 13a and transmitted to the sun gears S _L and S _R of the gear device 30.

  Then, the output side small gear 13b of the intermediate gear shafts 13L and 13R is engaged with the large diameter output gear 14a of the output gear shafts 14L and 14R via the idler gear 71 via the gear device 30, and the output side small gear 13b and the output are output. The torques of the electric motors 2L, 2R are further increased by the gear ratio with the gear 14a and output to the drive wheels.

  The rotor shafts 12L and 12R have a hollow structure penetrating in the axial direction, and an input gear 12a is provided at the ends of the rotor shafts 12L and 12R. Output gear shafts 14L and 14R are coaxially arranged inside the hollow rotor shafts 12L and 12R.

  The gear device 30 is configured by combining two planetary gear mechanisms 30L and 30R having the same three-element two-degree-of-freedom with coaxial intermediate gear shafts 13L and 13R. The planetary gear mechanisms 30L and 30R are of a double pinion type. A planetary gear mechanism is used.

Then, the planet carrier C _L of the first planetary gear mechanism 30L and the internal gear R _R of the second planetary gear mechanism 30R is coupled by a first coupling member 31, and the internal gear R _L of the first planetary gear mechanism 30L second a planet carrier C _R of the planetary gear mechanism 30R is coupled by the second coupling member 32.

Torque TM1 generated by the electric motor 2L is transmitted from the input gear 12a via the idler gear 70 to the input-side large-diameter gear 13a of the intermediate gear shaft 13L, and has a gear ratio between the input gear 12a and the input-side large-diameter gear 13a. is input is increased to the sun gear S _L of the first planetary gear mechanism 30L, transmitted to the input side large diameter gear 13a of the intermediate gear shaft 13R through the idler gear 70 torque TM2, which is generated by the electric motor 2R is the input gear 12a is inputted is increased by the gear ratio between the input gear 12a and the input side large-diameter gear 13a with the sun gear S _R of the second planetary gear mechanism 30R.

  The first coupling member 31 and the second coupling member 32 are provided with an output-side small gear 13b, and the output-side small gear 13b meshes with the large-diameter output gear 14a of the output gear shafts 14L and 14R via the idler gear 71. The torque increased by the gear ratio between the output side small-diameter gear 13b and the output gear 14a is connected to the left and right drive wheels via the drive shaft including the constant velocity joint 65a and is taken out.

In the third embodiment, the input from the electric motors 2L and 2R is the sun gears S _L and S _R , and the output to the drive wheels is the planet carrier C _L and the internal gear R _R , the planet carrier C _R and the internal It becomes gear _RL .

  Here, the driving torque transmitted by the gear device 30 according to the third embodiment will be described with reference to a velocity diagram shown in FIG.

Since the gear device 30 shown in FIG. 12 is configured by combining two planetary gear mechanisms 30L and 30R of the same double pinion, it can be expressed by two velocity diagrams as shown in FIG. Here, for ease of understanding, the two speed diagrams are shifted up and down, the speed diagram of the first planetary gear mechanism 30L is shown on the upper side, and the speed diagram of the second planetary gear mechanism 30R is shown on the lower side. Is shown. Further, similarly to the description in the first and second embodiments, in the following explanation of the velocity diagram and each calculation formula, the reduction ratio in each of the reduction gears 3L, 3R is omitted, and each sun gear S _L , the torque input to the S _R to remain TM1 and TM2.

In the gear device 30 shown in FIG. 12, the planet carrier C _L and the internal gear R _R, as shown by broken line in the drawing of FIG. 13, are coupled by a first coupling member 31, planet carrier C _R and the internal gear R _L is These are coupled by the second coupling member 32 as indicated by a broken line in the figure.

The torques TM1 and TM2 output from the electric motor 2L and the electric motor 2R are input to the sun gears S _L and S _R , respectively. On the other hand, driving torques TL and TR transmitted from the first coupling member 31 and the second coupling member 32 located in the middle on the velocity diagram to the left and right driving wheels are output.

  Also with the gear device 30 configured in this manner, the left drive is achieved by giving a torque difference (input torque difference) ΔTIN (= TM2−TM1) to the motor torques TM1 and TM2 generated by the electric motor 2L and the electric motor 2R. A drive torque difference ΔTOUT (= TR−TL) can be generated between the drive torque TL transmitted to the wheel and the drive torque TR transmitted to the right drive wheel.

The torque difference amplification factor α of the gear device 30 according to the third embodiment will be described. In the third embodiment, since the two double pinion planetary gear mechanisms 30L and 30R use gear elements having the same number of teeth, in the velocity diagram, the internal gear R _L and the planet carrier C _L And the distance between the internal gear R _R and the planetary carrier C _R are equal to each other. Further, the distance between the sun gear S _L and the internal gear R _L and the distance between the sun gear S _R and the internal gear R _R are also equal, which is b. The ratio of the length from the planet carrier C _L , C _R to the internal gear R _L , R _R and the length from the planet carrier C _L , C _R to the sun gear S _L , S _R is the ratio of the internal gear R _L , R _R It is equal to the ratio of the reciprocal number (1 / Zr) of the number of teeth Zr and the reciprocal number (1 / Zs) of the number of teeth Zs of the sun gears S _L and S _R. Therefore, a = (1 / Zr) and a + b = (1 / Zs).

  In the speed diagram of FIG. 13, when considering the balance of torque, the torque difference amplification factor α can be obtained. In FIG. 13, the arrow direction indicates the positive direction of the moment M.

The following equation (7) is calculated from the balance of the moment M with respect to the point of S _R.
b.TL + (a + b) .TR- (a + 2b) .TM1 = 0 (7)

The following equation (8) is calculated from the balance of the moment M with reference to the point of S _L.
-B.TR- (a + b) .TL + (a + 2b) .TM2 = 0 (8)

The following equation (9) is calculated from the equation (7) + the equation (8).
a. (TR-TL)-(a + 2b). (TM1-TM2) = 0
(TR-TL) = ((a + 2b) / a). (TM1-TM2) (9)

  In equation (9), (a + 2b) / a is the torque difference amplification factor α.

  When a = 1 / Zr and a + b = 1 / Zs are substituted, α = (2Zr−Zs) / Zs.

In the third embodiment, the electric motor 2L, input from 2R is the sun gear S _L, S _R, the output to the driving wheels planet carrier C _L and the internal gear R _R, a planet carrier C _R and the internal gear R _L , and the torque difference amplification factor α is (2Zr−Zs) / Zs.

  As described above, when different torques TM1 and TM2 are generated by the two electric motors 2L and 2R to give the input torque difference ΔTIN, the input torque difference ΔTIN is amplified in the gear device 30, and the driving is greater than the input torque difference ΔTIN. A torque difference ΔTOUT (= α · (TM1−TM2)) can be obtained.

  FIG. 14 is a skeleton diagram showing a gear configuration of a vehicle drive device according to the fourth embodiment of the present invention, and FIG. 15 is a torque difference by the gear device incorporated in the vehicle drive device according to the fourth embodiment of the present invention. It is a velocity diagram for demonstrating the amplification factor.

  The electric motor 2L and the electric motor 2R operate with electric power from a battery (not shown) mounted on the vehicle, are individually controlled by an electronic control device (not shown), and can generate and output different torques. . The driving force of the vehicle drive device 1 is transmitted to left and right drive wheels (not shown) via a drive shaft (not shown) including a constant velocity joint 65a.

The torques of the electric motors 2L and 2R mesh with the input side large gear 13a of the intermediate gear shafts 13L and 13R via the idler gear 70 and the input gear 12a of the rotor shafts 12L and 12R serving as the input gear shafts of the speed reducers 3L and 3R. , is transmitted is increased by the gear ratio between the input gear 12a and the input side large-diameter gear 13a planet carrier of the gear device 30 C _L and the sun gear S _R, a planet carrier C _R and the sun gear S _L.

  Then, the output side small gear 13b of the intermediate gear shafts 13L and 13R is engaged with the large diameter output gear 14a of the output gear shafts 14L and 14R via the idler gear 71 via the gear device 30, and the output side small gear 13b and the output are output. The torques of the electric motors 2L, 2R are further increased by the gear ratio with the gear 14a and output to the drive wheels.

  Then, by arranging the outer diameter surfaces of the electric motors 2L and 2R and the torque distribution gear device 30 provided integrally with the speed reducers 3L and 3R so as to overlap with each other, a useless space is compressed and the vehicle drive device 1 is compressed. The axial dimension of is reduced.

  The rotor shafts 12L and 12R have a hollow structure penetrating in the axial direction, and an input gear 12a is provided at the inboard side ends of the rotor shafts 12L and 12R. Output gear shafts 14L and 14R are coaxially arranged inside the hollow rotor shafts 12L and 12R.

  The gear unit 30 is configured by combining two identical planetary gear mechanisms 30L and 30R having three elements and two degrees of freedom on the same axis.

The planetary gear mechanisms 30L and 30R employ a double pinion planetary gear mechanism having two planetary gears. The planetary gear mechanism, a sun gear S _L provided coaxially, S _R and the internal gear R _L, and R _R, these sun gears S _L, when rotating the S _R, the sun gear S _L, S Planetary carriers C _L and C _R that are coaxially provided between _R and the internal gears R _L and R _R, and a plurality of double planets that are rotatably supported by the planet carriers C _L and C _R and mesh with each other. It consists of gears P _L and P _R. Here, the sun gears S _L and S _R and the planetary gears P _L and P _R are external gears having gear teeth on the outer periphery, and the internal gears R _L and R _R are internal gears having gear teeth on the inner periphery.

In the two planetary gears P _L and P _{R, one} of the two gears meshes with the sun gears S _L and S _R, and the other of the two gears meshes with the internal gears R _L and R _R. In the double pinion planetary gear mechanism as shown in FIG. 14, when the planet carriers C _L and C _R are fixed, the sun gears S _L and S _R and the internal gears R _L and R _R rotate in the same direction. In the velocity diagram shown in FIG. 15, the internal gears R _L and R _R and the sun gears S _L and S _R are arranged on the same side with respect to the planetary carriers C _L and C _R. In other words, the planet carrier C _L, C _R is the internal gear R _L, sun gear across the R _R S _L, located on the opposite side of the S _R, the internal gear R _L, when fixing the R _R is the sun The gears S _L and S _R and the planet carriers C _L and C _R rotate in the opposite directions.

In the velocity diagram shown in FIG. 15, the ratio of the length from the planet carriers C _L and C _R to the internal gears R _L and R _R and the length from the planet carriers C _L and C _R to the sun gears S _L and S _R Is equal to the ratio of the reciprocal number (1 / Zr) of the number of teeth Zr of the internal gears R _L and R _R and the reciprocal number (1 / Zs) of the number of teeth Zs of the sun gears S _L and S _R.

As shown in FIG. 14, the gear device 30 includes a first planetary gear mechanism 30L having a sun gear S _L , a planetary carrier C _L , a planetary gear P _L and an internal gear _RL , as well as the sun gear S _R and the planet carrier. C _R, and a second planetary gear mechanism 30R having a planetary gear P _R and the internal gear R _R is configured by combining coaxially.

Then, the sun gear S _L of the first planetary gear mechanism 30L and planet carrier C _R of the second planetary gear mechanism 30R is coupled with the first coupling member 31, and the planet carrier C _L of the first planetary gear mechanism 30L second The sun gear SR of the planetary gear mechanism 30 </ b> _R is coupled by the second coupling member 32.

As shown in FIG. 14, the torque TM1 generated by the electric motor 2R is input to the first coupling member 31 via the reduction gear train, and the torque generated by the electric motor 2L is input to the second coupling member 32. TM2 is input via the reduction gear train. Further, the internal gear R _L of the first planetary gear mechanism 30L is connected to the left driving wheel via the output gear shaft 14L, the internal gear R _R of the second planetary gear mechanism 30R right driving wheels through the output gear shaft 14R Connected to.

  Here, the drive torque transmitted by the gear device 30 will be described with reference to a velocity diagram shown in FIG. Since the gear device 30 is configured by combining two identical planetary gear mechanisms 30L and 30R, it can be represented by two velocity diagrams as shown in FIG. Here, for easy understanding, the two speed diagrams are shifted up and down, the speed diagram of the first planetary gear mechanism 30L is shown on the upper side, and the speed diagram of the second planetary gear mechanism 30R is shown on the lower side.

The speed diagram of the first planetary gear mechanism 30L and the speed diagram of the second planetary gear mechanism 30R indicate that the sun gears S _L and S _R and the planet carriers C _L and C _R are internal gears R _L and R _R. It is arranged on the left and right sides. That is, in FIG. 15, the planet carrier C _R of the second planetary gear mechanism 30R is arranged on the sun gear S _L of the first planetary gear mechanism 30L, first under the planet carrier C _L of the first planetary gear mechanism 30L the sun gear S _R of second planetary gear mechanism 30R is arranged.

In the gear device 30, elements located at both ends of the two velocity diagrams shown in FIG. 15 are joined to each other as shown by a broken line in the figure to form a first coupling member 31 and a second coupling member 32. The Then, the torque TM1 output from the electric motor 2R is applied to the first coupling member 31 via the reduction gear train. This is connected sun gear S _L to the first coupling member 31, part of the torque TM1 output from the electric motor 2R is to be given via the reduction gear train. The remainder of the torque TM1 output from the electric motor 2R is provided to the planet carrier C _R through the reduction gear train.

The torque TM2 output from the electric motor 2L is input to the second coupling member 32 via the reduction gear train. This second coupling member 32 connected to the sun gear S _R, a portion of the torque TM2 that is output from the electric motor 2L is to be given via the reduction gear train. The remainder of the torque TM2 that is output from the electric motor 2L is applied to the planet carrier C _L via a reduction gear train. Here, originally, the torques TM1 and TM2 output from the electric motors 2R and 2L are input to the coupling members 31 and 32 via the reduction gear trains, so that a reduction ratio is applied. For this reason, in the description of the velocity diagram and each calculation formula, the reduction ratio is omitted, and the torque input to each coupling member 31 and 32 remains TM1 and TM2.

Drive torques TL and TR transmitted from the internal gears R _L and R _R located in the middle of the speed diagram to the left and right drive wheels are output.

  By providing the torque difference (input torque difference) ΔTIN (= TM2−TM1) to the motor torques TM1 and TM2 generated by the electric motor 2R and the electric motor 2L by the gear device 30 thus configured, the left driving wheel A drive torque difference ΔTOUT (= TL−TR) can be generated between the drive torque TL transmitted to the right drive wheel and the drive torque TR transmitted to the right drive wheel. That is, according to this gear device 30, the relationship of the following formula (10) is obtained. The coefficient α is a torque difference amplification factor.

  (TL-TR) = α × (TM2-TM1) (10)

The torque difference amplification factor α of the gear device 30 according to the fourth embodiment will be described. Here, two double-pinion planetary gear mechanism 30L, 30R is due to the use of gear elements of the same number of teeth, in the velocity diagram, the distance between the internal gear R _L and a planet carrier C _L and the internal gear The distance between R _R and the planet carrier C _R is equal, and this is a. Further, the distance between the sun gear S _L and the internal gear R _L and the distance between the sun gear S _R and the internal gear R _R are also equal, which is b.

The torques TM1 and TM2 of the electric motor 2R and the electric motor 2L are input to the first and second coupling members 31 and 32 at both left and right ends, respectively, and the drive torques TL and TR are extracted from the internal gears R _L and R _R.

From the relationship between torque input and output, the following equation (11) is obtained.
TR + TL = TM1 + TM2 (11)

Further, expression of the left end (C _L, S _R portion) moment relative to the in the figure become the following equation (12). In the figure, the arrow direction indicates the positive direction of the moment M.

  0 = aTL + bTR− (a + b) TM1 (12)

  Summarizing TL and TR from these equations (11) and (12), the following equations (13) and (14) are obtained.

TL = ((a / (ba)) + 1) .TM2- (a / (ba)). TM1 (13)
TR = ((a / (ba)) + 1) .TM1- (a / (ba)). TM2 (14)

  From these equations (13) and (14), the drive torque difference (TL-TR) is the following equation (15).

(TL-TR) = ((a + b) / (ba)). (TM2-TM1) (15)

  In the case of the double pinion planetary gear mechanism, the length a is the reciprocal (1 / Zr) of the number of teeth Zr of the internal gear R, and the length a + b is the reciprocal (1 / Zs) of the number of teeth Zs of the sun gear S. Is rewritten as equation (16).

  (TL-TR) = (Zr / (Zr-2Zs)). (TM2-TM1) (16)

  From the above equations (10) and (16), the torque difference amplification factor α is Zr / (Zr−2Zs).

As described above, in the fourth embodiment, the inputs from the electric motors 2L and 2R are the sun gear S _R and the planet carrier C _L , the sun gear S _L and the planet carrier C _R , and the output to the drive wheels is The internal gears R _L and R _R are obtained.

  When different torques TM1 and TM2 are generated by the two electric motors 2R and 2L to give an input torque difference ΔTIN (= TM2−TM1), the gear device 30 amplifies the input torque difference ΔTIN and is larger than the input torque difference ΔTIN. A drive torque difference α · ΔTIN can be obtained. That is, even if the input torque difference ΔTIN is small, the gear device 30 can amplify the input torque difference ΔTIN with a predetermined torque difference amplification factor α, and drive torque TL transmitted to the left drive wheel and the right drive wheel, A driving torque difference ΔTOUT (= α · (TM2−TM1) = TL−TR) larger than the input torque difference ΔTIN can be given to TR.

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. The scope of the present invention is claimed. The equivalent meanings recited in the claims, and all modifications within the scope.

1: Vehicle drive device 2L, 2R: Electric motor 3L, 3R: Reduction gear 4L, 4R: Motor housing 4aL, 4aR: Motor housing body 4bL, 4bR: Outer wall 5: Rotor 6: Stator 9: Reduction gear housing 9a: Center Housing 9bL, 9bR: Side housing 11: Partition wall 12L, 12R: Rotor shaft 12a: Input gear 13L, 13R: Intermediate gear shaft 13a: Input side large gear 13b: Output side small gear 14L, 14R: Output gear shaft 14a: Output gear 30: torque distribution gear device 30L: first planetary gear mechanism 30R: second planetary gear mechanism 31: first coupling member 32: second coupling members 65a, 65b: constant velocity joint 65c: intermediate shafts 70, 71 : Idler gear 90: through oil passage C _L , C _R : planetary carrier P _L , P _R : planetary gear R _L , R _R : Internal gear S _L , S _R : Sun gear

Claims (16)

Two electric motors mounted on the vehicle and independently controllable, two speed reducers arranged between the two electric motors, and the torques from the two electric motors are incorporated into the two speed reducers. In a vehicle drive device comprising a gear device that distributes to wheels,
The speed reducer includes an input gear shaft including an input gear provided coaxially with a rotor shaft of the electric motor, an output gear shaft including an output gear coupled to a drive wheel, and an input gear shaft and an output gear shaft. An inboard of a vehicle having a hollow structure that has an input side large-diameter gear and an intermediate gear shaft that includes an output-side small-diameter gear and that penetrates the rotor shaft of the electric motor in the axial direction. The input gear is provided on the outer periphery of the side end, and an output gear shaft connected to the drive wheel is provided so as to pass through a rotor shaft having a hollow structure coaxially with the input gear shaft. A three-element two-degree-of-freedom planetary gear mechanism provided coaxially with a pair of left and right intermediate gear shafts having a large-side gear and an output-side small gear. Between the left and right gears An idler gear is provided between the output-side small-diameter gear and the output gear of the axle, and the center of the rotor shaft of the electric motor is determined from the distance from the center of the rotor shaft of the electric motor to the radial end of the stator of the electric motor. A vehicle drive device characterized in that the distance from the gear device to the gear device is increased and a part of the gear device provided on the left and right intermediate gear shafts is overlapped with the outer diameter surface of the electric motor. The gear device has a configuration in which two planetary gear mechanisms having three elements and two degrees of freedom are connected,
The planetary gear mechanism includes an internal gear, a planet carrier provided coaxially with the internal gear, a sun gear provided coaxially with the internal gear, and a plurality of planetary gears as revolution gears. ,
A first coupling member that couples one planet carrier and the other one element of the two planetary gear mechanisms; and a second coupling member that couples the same one element to the other planet carrier. ,
The input element of the gear device is coaxially connected to the input-side large-diameter gear of the intermediate gear shaft of the speed reducer, and the output-side small-diameter gear of the intermediate gear shaft is connected to the output element of the gear device. The vehicle drive device according to claim 1.   In the speed reducer, a gear train composed of an output side small diameter gear and an output gear of the intermediate gear shaft is arranged on the inboard side of the vehicle with respect to a gear train composed of the input side large gear on the input gear and the intermediate gear shaft. The vehicle drive apparatus according to claim 1, wherein the vehicle drive apparatus is configured as described above. The planetary gear mechanism is a single pinion planetary gear mechanism,
A first coupling member that couples one planetary carrier and the other sun gear of the two planetary gear mechanisms, and a second coupling member that couples one sun gear and the other planetary carrier,
The internal gear of the gear device is coaxially connected to the input-side large-diameter gear of the intermediate gear shaft of the reduction gear, and the output-side small-diameter gear of the intermediate gear shaft is coaxially connected to the planet carrier of the planetary gear mechanism. The vehicle drive device according to claim 2 or 3, characterized by the above.   The input side large-diameter gear meshed with the input gear and the idler gear through the intermediate gear shaft of the reduction gear, which is coaxial with the gear device, and the internal gear of the planetary gear mechanism are in an axial position where they overlap each other in the radial direction. The vehicle drive device according to claim 4, wherein the vehicle drive device is arranged. The planetary carrier of the planetary gear mechanism has a carrier flange that supports the planetary gear via a carrier pin and extends on the inboard side and the outboard side of the vehicle,
5. The vehicle drive device according to claim 4, wherein the planetary carrier is rotatably supported by two rolling bearings with respect to a reduction gear housing that houses the reduction gear.   The vehicle drive apparatus according to any one of claims 4 to 6, wherein an output side small-diameter gear of an intermediate gear shaft that meshes with an output gear is coaxially connected to an inboard side of the planetary carrier vehicle.   8. The vehicle drive device according to claim 4, wherein an internal gear of the planetary gear mechanism is rotatably supported by a rolling bearing with respect to the planet carrier.   The reduction gear housing that accommodates the two reduction gears has a three-piece configuration including a central housing and left and right side housings, and a partition wall that partitions the left and right is provided at a central portion of the central housing, and the first coupling member The vehicle drive device according to any one of claims 4 to 7, wherein the second coupling member penetrates the partition wall.   The idler gear provided between the input gear of the reduction gear and the input-side large-diameter gear of the intermediate gear shaft is a rolling bearing with respect to a shaft fixed by brackets on motor side walls of the left and right side housings of the reduction gear housing. The vehicle drive device according to claim 9, wherein the vehicle drive device is rotatably held by the vehicle.   The idler gear provided between the output side small-diameter gear and the output gear of the intermediate gear shaft of the speed reducer is rotatable by a rolling bearing with respect to a shaft fixed by a bracket to the partition wall surface of the central housing of the speed reducer housing. The vehicle drive device according to claim 9, wherein the vehicle drive device is held by the vehicle. In the gear device, the first coupling member and the second coupling member are arranged coaxially, one coupling member is a hollow shaft, and the other coupling member is a double shaft that is inserted into the hollow shaft. Structure,
The vehicle according to any one of claims 4 to 11, wherein the connection between the first coupling member and the second coupling member and a planet carrier to which the respective coupling members are coupled is spline fitting. Drive device.   The shaft member opposite to the spline fitting portion with the planet carrier is rotatably supported by a rolling bearing in the inner diameter side coupling member among the first and second coupling members. The vehicle drive device according to any one of 12. The planetary gear mechanism is a single pinion planetary gear mechanism,
A first coupling member that couples one planet carrier and the other internal gear of the two planetary gear mechanisms, and a second coupling member that couples one internal gear and the other planet carrier;
The sun gear of the planetary gear mechanism is coaxially connected to the input-side large-diameter gear of the intermediate gear shaft of the reduction gear, and the output-side small gear of the intermediate gear shaft is coaxially connected to the planet carrier of the planetary gear mechanism. The vehicle drive device according to claim 2, wherein: The planetary gear mechanism includes an internal gear, a planet carrier provided coaxially with the internal gear, a sun gear provided coaxially with the internal gear, and a plurality of double planetary gears as revolution gears. Have
When the planet carrier is fixed, the internal gear rotates in the same direction as the sun gear,
A first coupling member that couples one planet carrier and the other internal gear of the two planetary gear mechanisms, and a second coupling member that couples one internal gear and the other planet carrier;
The sun gear of the planetary gear mechanism is coaxially connected to the input-side large-diameter gear of the intermediate gear shaft of the reduction gear, and the output-side small gear of the intermediate gear shaft is coaxially connected to the planet carrier of the planetary gear mechanism. The vehicle drive device according to claim 2. The planetary gear mechanism includes an internal gear, a planet carrier provided coaxially with the internal gear, a sun gear provided coaxially with the internal gear, and a plurality of double planetary gears as revolution gears. Have
When the planet carrier is fixed, the internal gear rotates in the same direction as the sun gear,
A first coupling member that couples one planetary carrier and the other sun gear of the two planetary gear mechanisms, and a second coupling member that couples one sun gear and the other planetary carrier,
The planetary carrier of the gear device is coaxially connected to the input-side large-diameter gear of the intermediate gear shaft of the reduction gear, and the output-side small-diameter gear of the intermediate gear shaft is coaxially connected to the internal gear of the planetary gear mechanism. The vehicle drive device according to claim 2.

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