JP2017145931A - Vehicle drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To coaxially process a bearing fitting hole of a rolling bearing supporting a planetary carrier to an internal gear of a planetary gear mechanism constituting a gear device, with high accuracy in a vehicle drive device provided with the gear device for amplifying torque difference.SOLUTION: In a vehicle drive device provided with gear devices 30 for amplifying torque difference between right and left drive wheels, planetary gear mechanisms of the gear devices 30 have internal gears R, R, planetary carriers C, Cdisposed coaxially with the internal gear R, R, sun gears S, Sdisposed coaxially with the internal gears R, R, and planetary gears P, Pas revolution gears. External gears 13a as speed reduction mechanisms are connected to the internal gears R, R, and the internal gears R, Rare supported by the planetary carriers C, Cin a cantilever manner through rolling bearings 39a, so that bearing fitting holes 39b of the rolling bearings 39a can be coaxially formed with high accuracy.SELECTED DRAWING: Figure 2

Description

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

  In vehicles such as electric cars, 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 wheels, thereby controlling the turning moment of the vehicle It is known to do. When it is effective to generate a large difference in driving torque between the left and right drive wheels in order to achieve smooth turning of the vehicle and to suppress changes in vehicle behavior such as extreme understeer and extreme oversteer There is. For this reason, it is desirable to amplify the difference between the torques output from the two electric motors and transmit them to the left and right drive wheels.

  Patent Document 1 and Patent Document 2 include a gear device in which two planetary gear mechanisms having three elements and two degrees of freedom are coaxially arranged between two drive sources 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.

  The vehicle drive device disclosed in Patent Document 1 (hereinafter referred to as Conventional Technology 1) has a configuration as shown in the skeleton diagram shown in FIG.

  The vehicle drive device 100 includes left and right electric motors 102L and 102R mounted on the vehicle, left drive wheels 104L and right drive wheels 104R, a gear device 105 and reduction gear trains 106L and 106R provided therebetween. 107L and 107R.

  The electric motor 102L and the electric motor 102R 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 output shaft 102aL of the electric motor 102L and the output shaft 102aR of the electric motor 102R are connected to the coupling members 111 and 112 of the gear device 105 via reduction gear trains 106L and 106R, respectively. The output from the gear unit 105 is given to the left and right drive wheels 104L and 104R via the reduction gear trains 107L and 107R.

  The gear device 105 is configured by combining two identical planetary gear mechanisms 110L and 110R having three elements and two degrees of freedom on the same axis.

As the planetary gear mechanisms 110L and 110R, for example, single-pinion type planetary gear mechanisms are employed. The single-pinion type planetary gear mechanism includes a sun gear S _L , S _R and internal gears R _L , R _R provided on the same axis, and these sun gears S _L , S _R and internal gears R _L , R _R. A plurality of planetary gears P _L and P _R and planetary gears P _L and P _R are rotatably supported, and are provided coaxially with the sun gears S _L and S _R and the internal gears R _L and R _R. was planet carrier C _L, is composed of a C _R, the planetary gear P _L, P _R is engaged the sun gear S _L, S _R and the internal gear R _L, in the R _R. Here, the sun gear S _L, S _R and the planetary gears P _L, P _R is the external gear having gear teeth on the outer circumference, the internal gear R _L, R _R is the internal gear having gear teeth on the inner peripheral is there.

As shown in FIG. 9, the gear unit 105 includes a first planetary gear mechanism 110L having a sun gear S _L , a planetary carrier C _L , a planetary gear P _L and an internal gear _RL , as well as a sun gear S _R and a planet carrier. C _R, and a second planetary gear mechanism 110R 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 110L and the internal gear R _R of the second planetary gear mechanism 110R is coupled by a first coupling member 111, and the internal gear R _L of the first planetary gear mechanism 110L second The sun gear S _R of the planetary gear mechanism 110R is coupled by the second coupling member 112.

The torque TM1 generated by the electric motor 102L is input to the first coupling member 111 via the reduction gear train 106L, and the torque TM2 generated by the electric motor 102R is input to the second coupling member 112 by the reduction gear train 106R. Is input through. Further, the planet carrier C _R of the planetary carrier C _L and the second planetary gear mechanism 110R of the first planetary gear mechanism 110L, respectively reduction gear train 107L, through 107R left and right drive wheels 104L, the output is connected to the 104R It is taken out.

As described above, in the prior art 1, the inputs from the first electric motor 102L and the second electric motor 102R are S _L + R _R and S _R + R _L , and the outputs to the drive wheels 104L and 104R are C _L, the C _R.

  Next, the vehicle drive device disclosed in Patent Document 2 (hereinafter referred to as Conventional Technology 2) has a configuration as shown in the skeleton diagram shown in FIG.

  In FIG. 10, in order to make the difference from the prior art 1 easier to understand, the electric motors 102L and 102R are arranged on the left and right to make the same figure as in the prior art 1, and the same components are denoted by the same reference numerals. ing.

  As shown in FIG. 10, the vehicle drive device 100 is provided between a first electric motor 102L and a second electric motor 102R mounted on the vehicle, a left drive wheel 104L and a right drive wheel 104R, and these. A gear device 105 and reduction gear trains 106L and 106R are provided.

The first electric motor 102L and the second electric motor 102R operate with electric power from a battery (not shown) mounted on the vehicle, and are individually controlled by an electronic control device (not shown) to generate different torques. Can be output. The output shaft 102aL of the first electric motor 102L and the output shaft 102aR of the second electric motor 102R are connected to the sun gears S _L and S _R of the gear device 105 via reduction gear trains 106L and 106R, respectively. The output from the gear unit 105 is given to the left and right drive wheels 104L, 104R.

  Like the prior art 1, the gear device 105 of the prior art 2 is configured by combining two identical planetary gear mechanisms 110L and 110R having three elements and two degrees of freedom on the same axis. As the planetary gear mechanisms 110L and 110R, for example, single-pinion type planetary gear mechanisms are employed.

Then, the planet carrier C _L of the first planetary gear mechanism 110L and the internal gear R _R of the second planetary gear mechanism 110R is coupled by a first coupling member 111, the internal gear R _L of the first planetary gear mechanism 110L When the planet carrier C _R of the second planetary gear mechanism 110R is coupled by the second coupling member 112.

The first electric motor 102L torque TM1 generated in is input to the sun gear S _L of the first planetary gear mechanism 110L via a reduction gear train 106L, torque TM2 generated by the second electric motor 102R is decelerated It is input to the sun gear S _R of the second planetary gear mechanism 110R through a gear train 106R.

  The first coupling member 111 and the second coupling member 112 are connected to the left and right drive wheels 104L and 104R, respectively, and output is taken out.

In this prior art 2, the inputs from the electric motors 102L and 102R are S _L and S _R , and the outputs to the drive wheels 104L and 104R are C _L + R _R and C _R + R _L.

  In the above-described prior art 1 and prior art 2, when the two electric motors 102L and 102R generate different torques TM1 and TM2 to give the input torque difference ΔTIN, the gear device 105 receives the input torque difference. ΔTIN is amplified, and a driving torque difference ΔTOUT larger than the input torque difference ΔTIN can be obtained.

In the prior art 1 and the prior art 2, since the torque difference is amplified by connecting the internal gears R _L and R _R constituting the two planetary gear mechanisms and the coupling member, either the right or left inner gear is used. Since one of the coupling members that connect the gears R _L and R _R to another member always has a larger diameter than the other internal gears R _L and R _R , there is a problem that the apparatus becomes large.

  For this reason, the applicant of the present application has already filed a patent application for a vehicle drive device that is smaller and lighter than the gear device that amplifies the torque difference between the prior art 1 and the prior art 2 (Japanese Patent Application No. 2006). No. 023529).

  The vehicle drive device (prior application example 1) for which the applicant of this application has applied for a patent has the configuration shown in FIGS. 11 and 12.

A planetary gear mechanism constituting the gear device 300 in the vehicle driving apparatus 200 of Sakinegairei 1 210L, 210R, respectively internal gear R _L, and R _R, the internal gear R _L, planet carrier provided on R _R coaxial a C _L, and C _R, the internal gear R _L, the sun gear provided on R _R coaxial S _L, and S _R, the planetary gear P _L as a revolving wheel, and P _R. Gear 300, one of the planet carrier C _L and the other of the first coupling member 211 for coupling the sun gear S _R, a second coupling member for coupling one of the sun gear S _L and the other planet carrier C _R 212, the first coupling member 211 and the second coupling member 212 are arranged coaxially, and among the first coupling member 211 and the second coupling member 212, the second coupling member 212 is a hollow shaft, The coupling member 211 has a shaft inserted through the hollow shaft, and the shaft passing between the two planetary gear mechanisms 210L and 210R has a double structure, and the internal gear R _{L of the} planetary gear mechanisms 210L and 210R. , R _R and the input gear 213 of the speed reduction mechanism are engaged with and connected to external gears 217 provided on the internal gears R _L , R _R.

JP 2015-21594 A Japanese Patent No. 4907390

  By the way, since the vehicle drive device is mounted on the vehicle body, it is essential to reduce the size and weight in order to reduce the mounting space and secure a wide vehicle compartment space.

  Therefore, when the gear device is disposed between the speed reduction mechanisms, it is necessary to share the gears constituting the speed reduction mechanism and the gear device parts that amplify the torque difference in order to reduce the size.

  Further, when the gear device is disposed between the speed reduction mechanisms, each planetary gear mechanism constituting the gear device and the external gear as the speed reduction mechanism are connected to each mechanism (torque amplification mechanism or speed reduction mechanism). In order to rotate with high precision, it is conceivable to support with a rolling bearing.

In prior application example 1 in which the applicant of the present application has filed a patent application, as shown in FIGS. 11 and 12, the internal gears R _L and R _R and the planetary carriers C _L and C _R are connected by rolling bearings 214a and 214b. The planetary carriers C _L and C _R are supported rotatably, and both ends of the planet carriers C _L and C _R are supported by the rolling bearings 215a and 215b to improve the rotation accuracy.

Planet carrier C _L, C inner the _R gear R _L, the rolling bearing 214a for supporting against R _R, 214b, as shown in FIG. 12, the internal gear R _L, fitting the two bearings provided at both ends of R _R It is installed in the joint holes 216a and 216b.

However, it is difficult to precisely process the shaft centers of the two bearing fitting holes 216a and 216b positioned at both ends of the internal gears R _L and R _R with each other.

  Increasing the processing accuracy so that the shaft centers of the two bearing fitting holes 216a and 216b are aligned with each other may increase the cost.

  Accordingly, the present invention provides a vehicle drive device provided with a gear device for amplifying a torque difference, wherein a bearing fitting hole of a rolling bearing that supports a planet carrier with respect to an internal gear of a planetary gear mechanism constituting the gear device is coaxially provided. It is to be able to process with high precision.

  In order to solve the above-described problems, the present invention provides a three-element and two-degree-of-freedom planetary gear mechanism coaxially between two drive sources mounted on a vehicle and independently controllable and left and right drive wheels. Two combinations, a specific element of one planetary gear mechanism and a specific element of the other planetary gear mechanism are connected to each other by a first coupling member and a second coupling member to drive left and right from two driving sources. In the vehicle drive device provided with the gear device for amplifying the torque difference in the wheel, the planetary gear mechanism is provided coaxially with the internal gear, the planet carrier provided coaxially with the internal gear, and the internal gear. A sun gear and a planetary gear as a revolving gear, an external gear as a speed reduction mechanism is connected to the internal gear, and the internal gear is cantilevered via a rolling bearing with respect to the planet carrier. It is characterized by that.

  The rolling bearing that cantilever-supports the internal gear with respect to the planet carrier can be constituted by two deep groove ball bearings.

  The rolling bearing that cantilever-supports the internal gear with respect to the planet carrier may be constituted by a single deep groove ball bearing as long as the supporting rigidity can be ensured.

  The rolling bearing that cantilever-supports the internal gear with respect to the planet carrier may be a double-row angular ball bearing.

  The speed reduction mechanism is connected to a drive source, an input gear shaft having an input gear, an output gear shaft connected to a drive wheel and having an output gear, and between the input gear shaft and the output gear shaft by meshing of the gears. At least one or more intermediate gear shafts for transmitting power may be arranged, and an outer gear that meshes with the input gear of the input gear shaft may be provided on the outer peripheral portion of the internal gear.

  The external gear as a speed reduction mechanism provided in the internal gear may be formed integrally with the internal gear, or may be formed separately from the internal gear.

  The small-diameter gear that meshes with the output gear of the output gear shaft may be provided on the outboard side of the planet carrier, or may be provided on the inboard side of the planet carrier.

  As described above, according to the present invention, since the internal gear is cantilever-supported by the rolling bearing with respect to the planetary carrier, the bearing fitting hole in which the rolling bearing is arranged can be made one. It is possible to accurately form a bearing fitting hole for arranging the shaft on the same axis.

  Rolling bearings that support the internal gear with respect to the planetary carrier can have two deep groove ball groove holders arranged in a double row in one bearing fitting hole. One deep groove ball groove receiver may be arranged in a single row.

  In addition to deep groove ball bearings, rolling bearings can use double row angular contact ball bearings. Using double row angular contact ball bearings can increase support rigidity compared to using deep groove ball bearings. It becomes possible.

It is a cross-sectional top view which shows embodiment of the vehicle drive device of this invention. It is an enlarged view of the gear apparatus part of embodiment of FIG. It is an enlarged view of the gear apparatus part of other embodiment. It is an enlarged view of the gear apparatus part of other embodiment. It is an enlarged view of the gear apparatus part of other embodiment. It is an enlarged view of the gear apparatus part of other embodiment. It is explanatory drawing of the electric vehicle which showed the gear structure of the vehicle drive device which concerns on each embodiment with the skeleton figure. It is a speed diagram for demonstrating the torque difference amplification factor by the gear apparatus integrated in the vehicle drive device which concerns on each embodiment. It is a skeleton figure which shows the gear structure of the vehicle drive device which concerns on the prior art 1. FIG. It is a skeleton figure which shows the gear structure of the vehicle drive device which concerns on the prior art 2. FIG. It is a cross-sectional top view which shows the vehicle drive device of prior application example 1. It is an enlarged view of the gear apparatus part of FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  The electric vehicle AM shown in FIG. 7 is a rear wheel drive system, and includes a chassis 60, drive wheels 61L and 61R as rear wheels, front wheels 62L and 62R, and a two-motor vehicle drive device 1 according to the present invention. , A battery 63, an inverter 64, and the like. In FIG. 7, the gear structure of the vehicle drive device 1 is shown with the skeleton figure.

  The vehicle drive device 1 is provided between two electric motors 2L and 2R, which are mounted on a vehicle and can be controlled independently, and left and right drive wheels 61L and 61R and the two electric motors 2L and 2R. Two left and right reduction gears 3L and 3R are provided.

  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.

  As a mounting form of the two-motor type vehicle driving device 1, a front wheel driving method and a four wheel driving method may be used in addition to the rear wheel driving method shown in FIG.

  The left and right electric motors 2L and 2R in the two-motor type vehicle drive device 1 use the same standard electric motors having the same maximum output, and are housed in the motor housings 4L and 4R as shown in FIG. Yes.

  The motor housings 4L and 4R include cylindrical motor housing bodies 4aL and 4aR, outer walls 4bL and 4bR that close the outer surfaces of the motor housing bodies 4aL and 4aR, and reduction gears on the inner surfaces of the motor housing bodies 4aL and 4aR. It consists of inner walls 4cL and 4cR separated from 3L and 3R. The inner walls 4cL and 4cR of the motor housing bodies 4aL and 4aR are provided with openings through which the motor shaft 5a is drawn.

  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 electric motors 2L and 2R may be axial gap types.

  The rotor 5 has a motor shaft 5a in the center, and the motor shaft 5a is drawn from the openings of the inner walls 4cL and 4cR of the motor housing main bodies 4aL and 4aR to the reduction gears 3L and 3R, respectively. A seal member 7 is provided between the openings of the inner side walls 4cL and 4cR of the motor housing bodies 4aL and 4aR and the motor shaft 5a.

  The motor shaft 5a is rotatably supported by the rolling bearings 8a and 8b on the inner walls 4cL and 4cR and the outer walls 4bL and 4bR of the motor housing main bodies 4aL and 4aR (FIG. 1).

  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 perpendicular 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).

  A plurality of bolts 10 are used to fix side faces 9bL and 9bR of the reduction gear housing 9 on the side of the outboard side (outside the vehicle body) and the inner side walls 4cL and 4cR of the motor housing bodies 4aL and 4aR of the electric motors 2L and 2R. Thus, the two electric motors 2L and 2R are fixedly arranged on the left and right sides of the reduction gear housing 9 (FIG. 1).

  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 independent left and right accommodation chambers for accommodating the two speed reducers 3L and 3R are provided in parallel.

  As shown in FIG. 1, the reduction gears 3L and 3R are provided in a bilaterally symmetric shape. Power is transmitted from the motor shaft 5a, and the input gear shafts 12L and 12R having the input gear 12a are meshed with the input gear 12a. Intermediate gear shafts 13L and 13R having an output side small gear 13b meshing with an input side external gear 13a and an output gear 14a, and an output gear 14a. The constant velocity joints 65a and 65b are pulled out from the reduction gear housing 9 and This is a parallel shaft gear reducer provided with output gear shafts 14L, 14R that transmit torque to the drive wheels 61L, 61R via an intermediate shaft 65c (FIG. 7). The input gear shafts 12L and 12R, the intermediate gear shafts 13L and 13R, and the output gear shafts 14L and 14R of the left and right reduction gears 3L and 3R are coaxially arranged.

  Both ends of the input gear shafts 12L, 12R of the reduction gears 3L, 3R roll into bearing fitting holes 16a formed on both the left and right sides of the partition wall 11 of the central housing 9a and bearing fitting holes 16b formed in the side housings 9bL, 9bR. The bearings 17a and 17b are rotatably supported. The bearing fitting holes 16a and 16b have a stepped shape having a wall portion with which the outer rings of the rolling bearings 17a and 17b abut.

  The end portions on the outboard side of the input gear shafts 12L, 12R are drawn outward from the openings provided in the side housings 9bL, 9bR, and between the openings and the outer ends of the input gear shafts 12L, 12R. Is provided with an oil seal 18 to prevent leakage of the lubricating oil sealed in the speed reducer housing 9.

  The input gear shafts 12L and 12R have a hollow structure, and end portions of the motor shaft 5a are inserted into the hollow input gear shafts 12L and 12R. The input gear shafts 12L, 12R and the motor shaft 5a are connected by splines (including the same for serrations).

  At least one or more intermediate gear shafts 13L and 13R are arranged. In the embodiment shown in FIG. 1, the intermediate gear shafts 13L and 13R have a pair of intermediate gear shafts 13L and 13R.

  The intermediate gear shafts 13L and 13R constitute a stepped gear shaft having an input side external gear 13a meshing with the input gear 12a and an output side small diameter gear 13b meshing with the output gear 14a on the outer peripheral surface. At both ends of the intermediate gear shafts 13L and 13R, rolling bearings 20a and 20b are fitted 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. Is supported through. And the bearing fitting holes 19a and 19b have a stepped shape with a wall portion with which the outer rings of the rolling bearings 20a and 20b abut so that a first coupling member 31 and a second coupling member 32 to be described later pass. It penetrates.

  The intermediate gear shafts 13L and 13R arranged on the same axis are connected to the intermediate gear shafts 13L and 13R so that the drive torque applied from the two electric motors 2L and 2R is a torque difference between the left and right drive wheels 61L and 61R. A gear device 30 for amplifying and distributing the signal is incorporated.

  The gear device 30 includes a planetary gear mechanism having three elements and two degrees of freedom, which are coaxially combined with a pair of left and right intermediate gear shafts 13L and 13R arranged coaxially.

As shown in the enlarged view of FIG. 2, the planetary gear mechanism constituting the gear device 30 includes internal gears R _L and R _R incorporated in the large-diameter input-side external gear 13a of the intermediate gear shafts 13L and 13R, 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, P and _R, the planetary gear P _L, is connected to the P _R, the internal gear R _L, R _R and planet carrier C _L provided coaxially, C _R and the left one of the planet carrier C _L (in FIG. 2 FIG. ) And the other sun gear S _R (the right side of the figure in FIG. 2), one sun gear S _L (the left side of the figure in FIG. 2) and the other planet carrier C _R (the figure). a second coupling member 32 for coupling the two in the right hand side of the drawing), the internal gear R _L, linked to R _R, the input gear shaft 12L, 12R The intermediate gear 13a includes an input side external gear 13a of the intermediate gear shafts 13L and 13R meshing with the input gear 12a, and an output side small gear 13b of the intermediate gear shafts 13L and 13R meshing with the output gear 14a of the output gear shafts 14L and 14R. The output side small-diameter gear 13b of the shafts 13L and 13R is connected to the planetary carriers C _L and C _R.

When a plurality of pairs of intermediate gear shafts 13L and 13R are provided, the internal gears R _L and R _R connected to the input side external gear 13a are the input gear shafts of the plurality of pairs of intermediate gear shafts 13L and 13R. The output side small gear 13b is arranged to mesh with the gears provided on the driven intermediate gear shafts 13L and 13R of the plural pairs of intermediate gear shafts 13L and 13R. Placed in.

In the embodiment shown in FIG. 2, the internal gear R _L, R _R in connected input-side external gear 13a is an internal gear R _L, but are formed integrally with the R _R, it may be formed separately .

Further, in the embodiment shown in FIG. 2, the planet carrier C _L, the output-side small-diameter gear 13b which is connected to the C _R is the planet carrier C _L, although formed integrally with the C _R, and formed separately Also good.

  Further, in the embodiment shown in FIG. 2, the output side small gear 13b and the output gear 14a of the output gear shafts 14L and 14R are provided on the outboard side (outside of the vehicle) of the vehicle drive device 1, but FIG. As in the embodiment shown in FIGS. 5 and 6, the vehicle drive device 1 may be provided on the inboard side (the inside of the vehicle).

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 speed reducer 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 FIG. 1, the output-side small-diameter gear 13b is integrally formed on the outer peripheral surface of the hollow shaft portion 35 of the carrier flange 34a.

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

Further, each carrier flange 34a, 34b facing surface and a planetary gear P _L of, inserting the thrust plate 38 between the P _R, the planetary gear P _L, thereby achieving a smooth rotation of the P _R.

The internal gears R _L and R _R are cantilevered with respect to the planetary carriers C _L and C _R via rolling bearings 39a.

A bearing fitting hole 39b for fitting and supporting the rolling bearing 39a is provided at the end of the internal gears R _L and R _{R on} the inboard side.

  In the embodiment shown in FIGS. 1 and 2, two deep groove ball bearings are used in double rows as the rolling bearing 39a fitted in the bearing fitting hole 39b.

  If the support rigidity is satisfied even if two deep groove ball bearings are not used in a double row, a single deep groove is used as the rolling bearing 39a fitted in the bearing fitting hole 39b as in the embodiment shown in FIG. Ball bearings can be used in a single row.

  In the embodiment shown in FIGS. 1 and 2 and the embodiment shown in FIG. 3, the output side small gear 13b and the output gear 14a of the output gear shafts 14L and 14R are connected to the outboard side (outside of the vehicle) of the vehicle drive device 1. 4, 5 and 6, the output side small gear 13 b and the output gear 14 a of the output gear shafts 14 </ b> L and 14 </ b> R are connected to the inboard side of the vehicle drive device 1 (inside the vehicle). ).

In the embodiment shown in FIGS. 4, 5, and 6, a bearing fitting hole 39 b that fits and supports the rolling bearing 39 a is provided at the end portion on the outboard side of the internal gears R _L and R _R.

  In the embodiment shown in FIG. 4, two deep groove ball bearings are used in double rows as the rolling bearing 39a fitted in the bearing fitting hole 39b.

  In the embodiment shown in FIG. 5, a double-row angular ball bearing is used as the rolling bearing 39a fitted in the bearing fitting hole 39b.

The embodiment shown in FIG. 6, the internal gear R _L, and the internal tooth portion provided on the inner peripheral surface of the R _R, the internal gear R _L, another the input-side external gear 13a provided on the outer peripheral surface of the R _R respectively Body In this example, both are fastened by bolts 39c.

  Next, in the embodiment shown in FIG. 1 and FIG. 2 and the embodiment shown in FIG. 3, the carrier flange 34b on the inboard side and the rolling bearing 20a for supporting the hollow shaft portion 36 of the carrier flange 34b on the inboard side A collar 40 is arranged between the two.

  The first coupling member 31 and the second coupling member 32 that couple the two planetary gear mechanisms constituting the gear device 30 of the vehicle drive device 1 define the partition wall 11 that partitions the central housing 9a of the reduction gear 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 (second coupling member 32 in each embodiment) is a hollow shaft, and the other coupling member (in each embodiment). The first coupling member 31) has a double structure consisting of a shaft inserted through the hollow shaft.

In each embodiment, the end portion of the right side of the planetary gear mechanism of the second coupling member 32 consists of a hollow shaft, the spline 41 in the hollow shaft portion 36 of the carrier flange 34b on the inboard side of the planet carrier C _R provided , they are connected by spline fitting to the second coupling member 32 the planet carrier C _R.

In each embodiment, the end portion of the left planetary gear mechanism of the first coupling member 31, the spline 42 in the hollow shaft portion 35 of the carrier flange 34a on the outboard side of the planet carrier C _L provided, first the coupling member 31 to the planet carrier C _L are connected by spline fitting.

As described above, the two first coupling member 31 of the planetary gear mechanism and a second coupling member 32, by connecting the splined to the planet carrier C _L and the planet carrier C _R, two planetary gear mechanism Can be divided into left and right, and can be incorporated into the three-piece reduction gear housing 9 together with other reduction gear shafts from the left and right.

End of the planet carrier C _L of the second coupling member 32 has, on its outer peripheral surface, the external gear meshing with the planetary gears P _L of the left planetary gear mechanism is formed, the sun the external gear of the left planetary gear mechanism A gear S _L is configured.

The first coupling member 31 inserted through the second coupling member 32 constituted by a hollow shaft has a large diameter portion 43 at the end on the right planetary gear mechanism side, and on the outer peripheral surface of the large diameter portion 43, external gear is formed to mesh with the planetary gears P _R of the right planetary gear mechanism, the external gear constitutes the sun gear S _R of the right planetary gear mechanism.

Of the first coupling member 31 and second coupling member 32, the maximum diameter of the sun gear S _R are connected to the inner diameter side of the coupling member (first coupling member 31), the binding of the outer diameter side member (the second coupling by member 32) is set smaller than the minimum diameter of the spline hole of the inner surface of the hollow shaft portion 36 of the carrier flange 34b on the inboard side of the planet carrier C _R for mating, the inner diameter side of the coupling member (first coupling member 31 ) Can be easily incorporated.

  Between the outer peripheral surface of the inner diameter side coupling member (first coupling member 31) and the inner peripheral surface of the outer diameter side coupling member (second coupling member 32), there are needles 44 at both ends of the collar 44. The roller bearings 45 and 46 are interposed.

The first coupling member 31 and the second coupling member 32 and the planetary carriers C _L and C _R are fitted to the planetary carriers C _L and C _R (splines 41 and 42) by using a fitting tolerance slidable in the axial direction. Uneven load on the gear tooth surface due to the thrust force can be prevented.

Further, the axial movement of the first coupling member 31 and the second coupling member 32 and the planetary carriers C _L and C _R due to the sliding of the spline (splines 41 and 42) fitting portion is the outer diameter side coupling member (each implementation). In the embodiment, the second coupling member 32) is regulated by providing thrust bearings 47 and 48 at both ends.

A coupling member (first coupling member 31 in each embodiment) on the inner diameter side of a double-structure shaft that couples two planetary gear mechanisms is composed of a coupling member (first coupling member 31 in each embodiment) and a planet carrier (each In the embodiment, the shaft end opposite to the spline fitting with C _L ) is supported by the deep groove ball bearing 49 with respect to the other planet carrier (C _{R in} each embodiment).

  The coupling member (the first coupling member 31 in each embodiment) on the inner diameter side of the double-structure shaft that couples the two planetary gear mechanisms is provided with an oil supply hole 50 in the shaft center. In the oil supply hole 50 of the inner diameter side coupling member (first coupling member 31 in each embodiment), the thrust bearings 47 and 48 at both ends of the outer diameter side coupling member (second coupling member 32 in each embodiment) are positioned. Radial oil supply passages 51 and 52 are provided.

  The output gear shafts 14L and 14R have a large-diameter output gear 14a, and are formed in bearing fitting holes 53a formed on both surfaces of the partition wall 11 of the central housing 9a and bearing fitting holes 53b formed on the side housings 9bL and 9bR. It is supported by rolling bearings 54a and 54b. The bearing fitting holes 53a and 53b have a stepped shape having a wall portion with which the outer rings of the rolling bearings 54a and 54b come into contact.

  Outboard side ends of the output gear shafts 14L and 14R are drawn out of the reduction gear housing 9 from openings formed in the side housings 9bL and 9bR, and are pulled out to the outboard side of the output gear shafts 14L and 14R. The outer joint portion of the constant velocity joint 65a is splined to the outer peripheral surface of the end portion.

  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. 7).

  An oil seal 55 is provided between the end of the output gear shafts 14L and 14R on the outboard side and the opening formed in the side housings 9bL and 9bR, and leakage of the lubricating oil sealed in the speed reducer housing 9 and the outside Intrusion of muddy water from

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

  As shown in FIG. 7, the left and right electric motors 2 </ b> L and 2 </ b> R are operated by electric power supplied via an inverter 64 from a battery 63 mounted on the vehicle. The electric motors 2L and 2R are individually controlled by an electronic control device (not shown), and can generate and output different torques.

The torque of the motor shaft 5a of the electric motors 2L and 2R is the gear ratio between the input gear shaft 12a of the input gear shafts 12L and 12R of the reduction gears 3L and 3R and the large-diameter input side external gear 13a of the intermediate gear shafts 13L and 13R. And transmitted to the internal gears R _L and R _R of the gear device 30.

  Then, the output side small gear 13b of the intermediate gear shafts 13L and 13R meshes with the large diameter output gear 14a of the output gear shafts 14L and 14R via the gear device 30, and the number of teeth of the output side small gear 13b and the output gear 14a. The torque of the motor shafts 5a of the electric motors 2L and 2R is further increased by the ratio and output to the drive wheels 61L and 61R.

  The gear device 30 is configured by combining two identical planetary gear mechanisms of three elements and two degrees of freedom with coaxial intermediate gear shafts 13L and 13R, and adopts a single pinion type planetary gear mechanism as the planetary gear mechanism. ing.

The planetary gear mechanism is positioned between the sun gears S _L and S _R and the internal gears R _L and R _R provided on the same axis, and between the sun gears S _L and S _R and the internal gears R _L and R _R. A plurality of planetary gears P _L and P _R and planetary gears P _L and P _R are rotatably supported, and a planet carrier C is provided coaxially with the sun gears S _L and S _R and the internal gears R _L and R _{R. L,} composed of a C _R. Here, the sun gear S _L, S _R and the planetary gears P _L, P _R is the external gear having gear teeth on the outer circumference, the internal gear R _L, R _R is the internal gear having gear teeth on the inner peripheral is there. 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.

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.

As described above, the gear device 30 includes the first planetary gear mechanism 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 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 and the sun gear S _{R of} the second planetary gear mechanism are coupled to form the first coupling member 31, and the sun gear S _{L of} the first planetary gear mechanism is formed. When the planet carrier C _R of the second planetary gear mechanism forms a second coupling member 32 are coupled.

The torque TM1 generated by the electric motor 2L in the internal gear _RL of the first planetary gear mechanism is transmitted to the intermediate gear shaft 13L through the meshing of the input gear 12a of the input gear shaft 12L and the input side external gear 13a, and the intermediate gear shaft 13L. The torque transmitted to the shaft 13L is transmitted to the output-side small gear 13b of the intermediate gear shaft 13L via the first planetary gear mechanism, and the output gear of the output-side small gear 13b of the intermediate gear shaft 13L and the output gear shaft 14L. 14a meshes with the output gear shaft 14L and the drive torque TL is output to the drive wheel 61L.

Torque TM2 generated by the electric motor 2R to the internal gear R _R of the second planetary gear mechanism includes an input gear 12a of the input gear shaft 12R and the input-side external gear 13a is transmitted to the intermediate gear shaft 13R meshing, intermediate gear The torque transmitted to the shaft 13R is transmitted to the output-side small gear 13b of the intermediate gear shaft 13R via the second planetary gear mechanism, and the output gear of the output-side small gear 13b of the intermediate gear shaft 13R and the output gear shaft 14R. The drive torque TR is output from the output gear shaft 14R to the drive wheel 61R.

Electric motor 2L, the output from the 2R, each internal gear R _L of the two planetary gear mechanisms, given R _R, the first coupling member 31, the output from the second coupling member 32 is the driving wheel 61L, the 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.

Since the gear device 30 is configured by combining two planetary gear mechanisms of the same single pinion type, it can be represented by two velocity diagrams as shown in FIG. Here, for easy understanding, the two velocity diagrams are shifted up and down, the velocity diagram of the left planetary gear mechanism is shown on the upper side, and the velocity diagram of the right planetary gear mechanism is shown on the lower side. Originally, in each embodiment, the torques TM1 and TM2 output from the electric motors 2L and 2R are respectively input to the internal gears R via the input side external gears 13a that mesh with the input gears 12a of the input gear shafts 12L and 12R. _A reduction ratio is applied because it is input to _L and R _R , and the drive torques TL and TR extracted from the gear device 30 are transmitted to the left and right drive wheels 61L and 61R via the output-side small-diameter gear 13b that meshes with the output gear 14a. However, in order to facilitate understanding, the speed ratio and the calculation formulas shown in FIG. 8 are omitted in the explanation of the speed diagrams and the calculation formulas, and the internal gears R _L and R _R are omitted. The input torque remains TM1 and TM2, and the driving torque remains TL and TR.

Two planetary gear mechanism constituting the gear device 30, due to the use of gear elements of the same number of teeth, in the speed diagram and distance and the internal gear R _R of the internal gear R _L and the planet carrier C _L the distance between the planet carrier C _R are equal, which is referred to as a. Further, the distance between the sun gear S _L and the planet carrier C _L and the distance between the sun gear S _L and the planet carrier C _R are also equal, and this 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 (11) is calculated from the balance of the moment M based on the point of R _R. In FIG. 8, the arrow direction M in the figure is the positive direction of the moment.
a * TR + (a + b) * TL- (b + 2a) * TM1 = 0 (11)

The following equation (12) is calculated from the balance of moment M with reference to point R _L.
-A.TL- (a + b) .TR + (b + 2a) .TM2 = 0 (12)

The following expression (13) is obtained from the expression (11) + the expression (12).
-B. (TR-TL) + (2a + b). (TM2-TM1) = 0
(TR-TL) = ((2a + b) / b). (TM2-TM1) (13)

  (2a + b) / b in the equation (13) is the torque 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 present invention, the electric motor 2L, input from 2R is, R _L, R _R, and the drive wheels 61L, the output of the 61R becomes _{S R + C L, S L} + C R.

  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 prior art 1 and the prior art 2, since the internal gear R is included in the left and right connecting members of the two planetary gear mechanisms of the gear device 105 that is the torque difference amplifying mechanism, the coupling that connects either the left or right internal gear and another member. One of the members must have a larger diameter than the other internal gear R.

In the present invention, connection of the two planetary gear mechanism constituting the gear device 30 is a torque difference distribution mechanism, the sun gear S _L and the planet carrier C _R, since it is the sun gear S _R and the planet carrier C _L, the internal gear A connecting member having a larger diameter than R _L and R _R is not required. For this reason, in this invention, since the torque difference distribution mechanism can be made smaller than those of the prior art 1 and the prior art 2, the vehicle drive device 1 for an electric vehicle incorporating the torque difference distribution mechanism is made smaller and lighter. Can be

  By reducing the size and weight of the vehicle drive device 1 for an electric vehicle, the degree of freedom of the vehicle body mount layout of peripheral accessories is improved along with the vehicle body mount layout of the vehicle drive device 1.

  Further, there is a merit that the vehicle interior space is expanded by downsizing the vehicle drive device 1.

  In each embodiment, the case where the electric motors 2L and 2R are used as the two drive sources and the same standard electric motor having the same maximum output is illustrated, but the two drive sources are not limited thereto.

  The vehicle on which the vehicle drive device 1 is mounted is not limited to an electric vehicle or a hybrid electric vehicle, and may be, for example, a fuel cell vehicle that uses the first electric motor 2L and the second electric motor 2R as driving sources. Good.

  The present invention is not limited to the above-described embodiments, and can be further implemented in various forms without departing from the gist of the present invention.

1: Vehicle drive device 2L, 2R: Electric motor 3L, 3R: Deceleration device 4L, 4R: Motor housing 4aL, 4aR: Motor housing body 4bL, 4bR: Outer wall 4cL, 4cR: Inner wall 5: Rotor 5a: Motor shaft 6 : Stator 7: Sealing members 8a and 8b: Rolling bearing 9: Reduction gear housing 9a: Central housing 9bL and 9bR: Side housing 10: Bolt 11: Partition walls 12L and 12R: Input gear shaft 12a: Input gear shafts 13L and 13R: Intermediate Gear shaft 13a: Input side external gear 13b: Output side small diameter gears 14L, 14R: Output gear shaft 14a: Output gears 16a, 16b: Bearing fitting holes 17a, 17b: Rolling bearing 18: Oil seals 19a, 19b: Bearing fitting Hole 20a, 20b: Rolling bearing 30: Gear device 31: First coupling member 32 : Second coupling member 33: carrier pins 34a and 34b: carrier flanges 35 and 36: hollow shaft portion 37: needle roller bearing 38: thrust plate 39a: rolling bearing 39b: bearing fitting hole 39c: bolt 40: collar 41, 42: Spline 43: Large diameter portion 44: Collar 45, 46: Needle roller bearings 47, 48: Thrust bearing 49: Deep groove ball bearing 50: Oil supply holes 51, 52: Oil supply passages 53a, 53b: Bearing fitting holes 54a, 54b: a rolling bearing 55: oil seal 60: chassis 61L, 61R: drive wheels 62L, 62R: front wheel 63: battery 64: inverter 65a, 65b: the constant velocity joint 65c: intermediate shaft AM: electric vehicle C _L, C _R: planetary The carrier M: moment P _L, P _R: planetary gear _{R L,} R R: internal gear S _L, S _R: the sun gear TM1, M2: Torque generated by the electric motor TL, TR: drive torque Zr: internal gear teeth Zs: number of teeth a of the sun gear, b: distance α torque difference gain DerutaTIN: input torque difference DerutaTOUT: drive torque difference

Claims (9)

  Two planetary gear mechanisms with three elements and two degrees of freedom are coaxially combined between two drive sources mounted on the vehicle and independently controllable and the left and right drive wheels, and specific elements of one planetary gear mechanism And a specific element of the other planetary gear mechanism connected to each other by a first coupling member and a second coupling member, and a vehicle provided with a gear device that amplifies a torque difference from two drive sources to the left and right drive wheels In the drive device, 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 planetary gear serving as a revolving gear. And an external gear as a speed reduction mechanism is connected to the internal gear, and the internal gear is cantilevered via a rolling bearing with respect to the planetary carrier.   2. The vehicle drive device according to claim 1, wherein the rolling bearing that cantilever-supports the internal gear with respect to the planet carrier is two deep groove ball bearings.   2. The vehicle drive device according to claim 1, wherein the rolling bearing that cantilever-supports the internal gear with respect to the planet carrier is a single deep groove ball bearing.   2. The vehicle drive device according to claim 1, wherein the rolling bearing that cantilever-supports the internal gear with respect to the planet carrier is a double-row angular ball bearing.   The speed reduction mechanism is connected to a drive source and has an input gear shaft having an input gear, an output gear shaft connected to a drive wheel and having an output gear, and an engagement between the input gear shaft and the output gear shaft by meshing of the gears. The intermediate gear shaft for performing power transmission is arranged at least one or more, and an external gear that meshes with the input gear of the input gear shaft is provided on the outer peripheral portion of the internal gear. Vehicle drive device.   The vehicle drive device according to claim 5, wherein an external gear as a speed reduction mechanism provided on the internal gear is formed integrally with the internal gear.   The vehicle drive device according to claim 5, wherein an external gear as a speed reduction mechanism provided in the internal gear is formed separately from the internal gear. The vehicle drive device according to any one of claims 5 to 7, wherein a small-diameter gear that meshes with an output gear of the output gear shaft is provided on an outboard side of the planetary carrier. The vehicle drive device according to any one of claims 5 to 7, wherein a small-diameter gear that meshes with an output gear of the output gear shaft is provided on an inboard side of the planet carrier.

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