JPH02306828A - Both wheel independent driving device for automobile - Google Patents

Abstract

PURPOSE:To achieve miniaturization and reduction in weight by receiving respective speed reducer means in a housing having first and second chambers divided by a partition wall, and directly mounting respective electric motors facing each other with the partition wall of the housing between them. CONSTITUTION:A reduction gear means RG1 is provided, which means is formed of a reduction gear line GI1 consisting of a small gear SG1 and a large gear LG1 engaged therewith, each of which has an input shaft and an output shaft, respectively, and a reduction gear line GII1 consisting of a small gear SG2 parallel to the gear SG1 and a large gear LG2 engaged therewith, each of which has an input shaft and an output shaft, respectively. A speed reducer I1 formed of a partition wall PW1 fixing the bearings of the respective gears, chambers RI1, RII1 partitioned by this partition wall, a lubricating oil sump part TK1 disposed in the bottom thereof, and a housing HA1 is provided. A pair of electric motors II1 having its output shaft connected to the respective input shafts of the gears SG1, SG2 of the gear lines GI1 and GII2 and a driving force transmission means III1 connected to the respective output shafts of the large gears LG1, LG2 to transmit the driving force from the reduction gear means RG1 to respective driving wheels of a vehicle are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a two-wheel independent drive system for a motor vehicle, and more specifically, the present invention relates to a two-wheel independent drive system for a motor vehicle, and more specifically, the drive torque of both wheels of a motor vehicle can be freely changed individually. This relates to a drive device.

[Conventional technology and its problems]

2. Description of the Related Art Conventionally, as a drive device that effectively transmits power generated by a prime mover to drive wheels, there has been a drive device that employs a differential mechanism. However, with this drive system, if one of the left or right drive wheels comes off and becomes unable to drive, it becomes impossible to transmit torque to the other drive wheel.
I can't escape by myself. Furthermore, if a sudden disturbance such as a crosswind occurs, the course will be changed and the vehicle will be in a dangerous situation, which is difficult to avoid. Furthermore, when the vehicle accelerates or decelerates rapidly on a slippery road such as a snowy or frozen road, there is a problem in that the wheels slip and the vehicle skids, creating a dangerous situation.

As a method to solve these problems, a drive system has been proposed that significantly improves the running performance of a vehicle by freely changing the drive torque of both wheels of the vehicle.

One of these drive devices is "Development of a high-output electric two-wheeled vehicle with a motor directly attached to the drive shaft of the wheel", Tokyo International Electric Vehicle Forum 8.
G Papers Preprint Collection, pages 45 to 48, published September 1986). However, at the current level, this drive device has a discrepancy between the speed-torque characteristics of the motor and the characteristics required for the vehicle, and is only applicable to specific vehicles such as hobby cars, and its range of use is limited. There was a problem that it could not be applied to

In addition, as for this conventional drive device, "Wheel motor with an integrated structure of drive device and wheels"("Research and development of electric vehicles" - Research results of 6 years under the large project system, pages 515 to 527, (Published by the Agency of Industrial Science and Technology, Ministry of International Trade and Industry, September 1978).

This drive system allows the drive torque of both wheels of the vehicle to be changed individually, and also makes it possible to reduce the size of the vehicle. However, this device receives strong impacts from uneven road surfaces, so parts that require precision construction, such as gears and motors, need to be made stronger. Also,
A brake device is usually disposed around the wheels of a vehicle, and braking energy is consumed in this area, resulting in a high temperature atmosphere around the area. However, it is difficult to secure a ventilation path for cooling in the vicinity of this part, and forced cooling using cooling oil or the like is essential, which complicates the device configuration in the vicinity of this part. Furthermore, in this case, there is a problem in that when a tire of a vehicle is damaged, it is not possible to easily replace the wheel, and replacement takes much effort and time.

In addition, this conventional drive system "drives the left and right wheels independently with separate electric motors, and controls the torque and rotational speed given to the left and right wheels by controlling the electric power supplied to each electric motor. There is an electric vehicle control device designed to cause the vehicle to run in the opposite direction (Japanese Patent Application Laid-open No. 48-4914). This device allows the reduction gear and electric motor to be separated from the driving wheels, which makes it possible to separate the electric motor and reduction gear from the high-temperature brake equipment, which is advantageous in terms of cooling and frees up space for installation. It was possible to obtain greater driving force compared to a device with an integrated structure of the device and wheels. However, in this device, it is necessary to fit two sets of devices, a speed reducer and an electric motor connected to the driving wheel shaft, into a limited space between the two wheels, so it is unavoidable that these devices come close to the wheels. For this reason, it is easy to receive vibration shocks caused by uneven road surfaces (and the bearings and other parts must be configured to withstand this, which increases the size of the device.Also, since this device is configured for each wheel, The load is shared between each part.However, since the wheels are located on the outermost wall of the vehicle and the reducer and electric motor are placed inside, this load is distributed to the ends of the entire device. This results in a single point load, complicating the support of the entire device including the wheels on the vehicle body, and requiring additional strength.

Therefore, the present inventors conducted intensive research to solve the problems of the prior art as described above, and as a result of conducting various systematic experiments, they came up with the present invention.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a small and lightweight two-wheel independent drive system for an automobile, which can freely change the drive torque of both wheels of a vehicle and significantly improve the running performance of the vehicle.

The present inventors focused on the following points regarding the above-mentioned problems of the prior art. That is, in the conventional device described above, since the drive device is composed of wheels for each wheel, parts for each wheel are placed on the left and right with the center between the wheels, and the reducer etc. approaches the wheel side, causing the above-mentioned problem. It causes various problems. Furthermore, if the device is configured for each wheel, a support device is required for each wheel, making it difficult to reduce the number of parts and hindering miniaturization. In order to solve these problems, the inventors of the present invention focused on creating an integrated structure in which the drive wheels, the equalizer, the electric motor, etc. are concentrated near the center of both drive wheels. However, although it is possible to achieve some miniaturization by simply combining this integrated structure with conventional technology, the shape cannot be accommodated in the limited space under the vehicle body, and the distance between the devices and the road surface is too close. This will make it difficult to drive on rough roads, and if the space is located in the upper body of the vehicle, the space will enter into the passenger compartment, worsening the comfort inside the vehicle.

Therefore, the inventors of the present invention adopted a housing structure having a first and second chamber separated by a partition wall, in contrast to the conventional structure in which the reducer/S housing was separately provided. Accordingly, the respective reduction means are housed in the housing, and the respective electric motors are directly mounted facing each other with the partition wall of the housing in the middle, and the driving force is taken out from the mounting side of the respective electric motors to drive the drive wheels. By transmitting the information to the
■In order to satisfy the various characteristics required by the vehicle, a planetary gear type speed reducer was adopted as the speed reduction means without changing the size of the housing, making it possible to output high torque. Therefore, we focused on solving the main problems of the prior art described above.

[Description of the First Invention] Structure of the Invention As shown in FIG. 1 pinion SG,
and a first large gear LG meshed with the first small gear SG.
, and has an input shaft on one surface of the first small gear SG, and an output shaft on one surface of the first large gear LG. and a second small gear SG2 disposed parallel to the first small gear SG1, and a second large gear LG meshed with the second small gear S62.

The first reduction gear train G1. A second reduction gear train G U having an input shaft of a second small gear SG and an output shaft of a second large gear LG2 on a surface opposite to the surface having an input/output shaft of
+ a deceleration means RG consisting of; a partition wall PWI fixing bearings that rotatably support the respective gears; and the first deceleration gear train G partitioned by the partition wall PW.
1. and a second deceleration float train G[1, respectively, a first chamber RI and a second chamber RII, and the first chamber R1.
, and the lubricating oil reservoir T disposed at the bottom of the second chamber RII.
K.

a housing HA + consisting of; and a reducer 1 consisting of
1, and the output shaft is the first reduction gear train G1. and first and second small gears SG of the second reduction gear train GIl,
, SG2, a pair of electric motors 1 connected to their respective input shafts, and the speed reduction means RG.

a driving force transmitting means (1) connected to the respective output shafts of the first and second large gears LG, LG, and transmitting the driving force from the decelerating means RG to the driving wheels of the vehicle; It is characterized by consisting of.

The two-wheel independent drive system for an automobile of the present invention having the above-mentioned configuration connects the input shaft of the small gear of the reduction means constituted by large and small gears to the output shaft of the electric motor, and connects the electric motor to the output shaft of the reduction gear. Since it is directly attached to the housing, parts such as shaft couplings are not required, and there is no need to provide a mounting part for the electric motor on the vehicle.

In addition, by using a housing that has a first chamber and a second chamber, only one partition wall is required to fix the bearings that support the gears of the two reduction gear trains, which reduces the overall size of the reduction gear. Weight reduction can be achieved.

In addition, by arranging the reduction gear trains for each wheel in a parallel arrangement facing each other in the same reduction gear housing, and configuring the transmission path of the electric motor, reduction gear, and axle shaft in a figure 33 shape, the weight part is reduced in speed. It can be concentrated near the machine, and the size and weight of the entire device can be minimized.

Furthermore, by arranging the reducer and electric motor centrally between the drive wheels, the moment of inertia of the vehicle body in the yaw and roll directions is minimized, and the deterioration of vehicle motion caused by the installation of this drive device is minimized. did. That is, the devices can be installed centrally between the wheels, and increases in inertia of the vehicle body in one direction and the roll direction, which impede high-speed operation of the vehicle, can be minimized. Furthermore, by centrally arranging the device in the center of the vehicle, the space between the device and the wheels becomes wider. Therefore, by making the axle shaft a universal joint,
By fixing the device to the vehicle, it is possible to construct an independent suspension system with a smaller inertial mass compared to a conventional device in which the load of each wheel is received by a dedicated drive device.

[Description of other inventions]

Other inventions related to the two-wheel independent drive system for automobiles of the present invention will be described below.

As shown in FIG. 2, the device of the second invention of the present invention is the two-wheel independent drive device for an automobile of the first invention, in which the reduction means of the reduction gear is connected to the first pinion SG3 and the first pinion SG3. S.G.
a first large gear LG meshed with the first small gear SG, having an input shaft on one surface of the first small gear SG;
a first reduction gear train G12 having an output shaft on one side of the large gear LG; a sun gear SUG fixed coaxially with the large gear LG; and a housing HA2 located coaxially with the sun gear SUG. a ring gear RNG fixed to, and
The sun gear SUG meshes with both the sun gear SUG and the ring gear RNG so as to revolve around the outside of the sun gear 5UG1 while rotating with the rotation of the sun gear SUG.

Planetary gears PG+ are arranged facing each other around the axis of
A first planetary gear mechanism P1. a second small gear SG disposed in parallel with the first small gear S63; and a second large gear LG meshed with the second small gear SG. , and a first reduction gear train G1. a second reduction gear train G II 2 having an input shaft of a second small gear SG and an output shaft of a second large gear LG on a surface opposite to a surface having an input/output shaft; , a sun gear 5UG2 coaxially fixed to the sun gear 5UG2, a ring gear RNG2 fixed to the housing HA 2 coaxially with the sun gear 5UG2, and a sun gear RNG2 meshing with both the sun gear 5UG2 and the ring gear RNG2.
a second planetary gear 14pn consisting of a planetary gear PG2 arranged opposite to each other around the axis of the sun gear 5UG2 so as to revolve around the outside of the sun gear 5UG2 while rotating with the rotation of the second planetary gear PG2; 2 reduction means RGB,
It is characterized in that it is constituted by a deceleration means RG2 consisting of the following.

The device of the second invention has the following features compared to the device of the first invention:
A planetary gear mechanism is added to the speed reduction means of the speed reducer.
By integrating the large gear and the sun gear, the increase in the number of parts is minimized, the size of the housing etc. of the device of the first invention is not changed, and the weight is minimized, and moreover, the torque is greater than that of the device of the first invention. can be output.

Further, in the device of the third aspect of the present invention, in the housing HA of the reduction gear 1, a lubricating oil reservoir TK at the bottom of the housing HA is provided.
The present invention is characterized in that a cooling means is provided for suppressing a rise in temperature of the speed reduction means by splashing lubricating oil thereon.

As a result, a lubricating oil reservoir is provided at the bottom of the housing that houses the deceleration means, and the lowest part of the large gear is brought into contact with this curved surface. Since the lubrication means is provided, local temperature rises can be suppressed by equalizing and reducing the temperature rises of both speed reduction means without the need to create a special lubrication device.

In particular, when this third invention is applied to the device of the second invention, a cavity is provided in the component parts of the planetary gear mechanism, and when the component parts rotate, the mist-like oil in the cavity is pushed out by centrifugal force. By providing an oil supply means that utilizes the pumping action, it is possible to supply the lubricating oil to the planetary gear bearing, to which it is normally difficult to supply oil. In this way, by using the simply configured cooling means based on the circulation of the lubricating oil mist in the cavity, it is possible to suppress the local temperature rise of the deceleration means without providing a special forced oil supply device.

Further, in the above-described device of the present invention, the mounting position of the electric motor is changed to the large gears LGS, LG of the reducer ■, as shown in FIG.
Even if they are arranged so as to face each other around the axis of reducer 6, as shown in Fig.
They may be opposed to each other at a predetermined angle about the axis. In the case of arrangement as shown in FIG. 3, since the gear meshing portions serving as heat generating portions are dispersed, the thermal influence on the housing HA3 tends to be uniform. Furthermore, since the moment around the driving force transmission means (1), that is, the axle shaft axis, is stabilized, installation to the vehicle becomes easy. When arranged as shown in Fig. 4, the rotation detector of each electric motor should be separately installed at a position opposite to the electric motor (2) with the small gear SG of the reducer 4 in between. I can do it. Therefore, this rotation detector can be separated from the electric motor (4), which is at the highest temperature, and the temperature resistance performance of the detector can be relaxed.

Furthermore, since the length of the entire device in the left-right direction in the figure (in the longitudinal direction of the vehicle) can be reduced accordingly, the weight of the device can be more concentrated in the center between the wheels.

In this case, the electric motor (4) on the side of the first reduction gear train and the electric motor (4) on the side of the second reduction gear train have a circumferential angle of 120 degrees around the large gear shaft of the reduction gear (4). degree~15
It is preferable to arrange it within an angular range of 0 degrees. When facing each other at such an angle, the meshing parts of the gears, which generate heat, are dispersed appropriately, so the heat effect on the housing becomes more uniform. Since the load moment due to the weight of the surrounding equipment is very stable, the installation strength to the vehicle can be reduced, and furthermore, it can be sufficiently stored in the space formed by the vehicle frame and the ground to avoid interference between various parts. I can do it.

Further, in the above invention, the gear train may further include small gears each having helical teeth in opposite directions, and large gears meshing with the small gears. In this case, the thickness of the gear can be minimized by employing helical teeth in the gear.

Furthermore, each gear train can be composed of small gears and large gears having helix angles in opposite directions. In this case, the thrust direction load generated by each gear is canceled out, and the support load near the bearing can be alleviated. In other words, the axial force generated when using helical gears acts to cancel each other out with the forces generated by the respective reduction means.
The shaft holding strength can be made smaller, and a lighter housing can be realized.

〔Example〕

! DESCRIPTION OF THE PREFERRED EMBODIMENTS A two-wheel independent drive system for an automobile according to a first embodiment of the present invention will be described with reference to FIGS. 5 and 6. FIG.

As shown in FIG. 5, the two-wheel independent drive system for automobiles of this embodiment comprises a speed reducer 1 (
. , an electric motor l110, and a driving force transmission means Into.

The housing 1 has a daruma-shaped outer shape when viewed in the axial direction, and is composed of a first part 2 that contacts the face and a second part 3 that contacts the abdomen, each of which has an axis at its center.

The second portion 3 has cylindrical protrusions 4 on both sides in the axial direction about the axis, and the protrusions 4 have a rectangular shape when cut along a plane passing through the axis.

Note that the housing l is provided with a partition wall 5 at a position on a symmetrical axis such that the protruding portion 4 of the second portion 3 is left and right symmetrical.

The partition wall 5 has a daruma shape like the housing l, and a hollow cylindrical shaft 7 is provided in the second portion 6 corresponding to the belly.
a partition wall 5 between the hollow cylindrical shaft 7 and the outer wall of the housing 1;
has a sector-shaped opening 8.

In the first part 2 of the housing 1, surfaces 13 and 14 on the output shafts 11 and 12 sides of electric motors 9 and 10 are in close contact with each other, and three bolts 15, 16 and 17 are attached to the first part 2 of the housing 1.
It is firmly attached to the housing 1 by.

The first part 2 of the housing 1 has helical pinion gears 18 and 19 each having a different helix angle with the partition wall 5 as an axis of symmetry. The small gear 18.19 has boss portions 20.21 at both ends, the outer diameter of which is finished with high precision.
．． The shaft center of 21 is a spline hole 22, 23.

The spline holes 22, 23 are connected to the motor output shaft 11.
12 through a spline connection.

An inner race of an angular contact ball bearing 24.25 is press-fitted into the outer diameter of the small gear boss portion 20.21, and an outer race of the angular contact ball bearing 24.25 is provided on the outer wall of the first part 2 and the partition wall 5 of the housing. It is installed in holes 26 and 27.

An oil seal 28 is driven into the housing l on the motor output shaft insertion side of the outer wall of the first portion 2 of the housing,
The lip portion is in contact with the outer diameter of the small gear boss 20.

The large gear 29.30 meshes with the small gear 18.19 to constitute a speed reduction means, and has a cross-sectional shape in which the gear portion and the boss portion become thinner toward the outside in the radial direction. A shaft 37 that is connected by a predetermined number of arms 31, 32, has a cylindrical hole 33, 34 on one side, has a hollow boss shape 35, 36 on the other side, and has an internal spline at the tip.
．． 38 is arranged so as to protrude.

A deep groove ball bearing 39.40 outer race is inserted into the cylindrical hole 33.34 of the large gear 29.30, and the bearing 3
9.40 Inker race is the partition wall 5 of the housing 1
It is press-fitted into the hollow cylindrical shaft 7 of the hollow shaft. Furthermore, the shafts 37, 38 with internal splines are provided with tapered roller bearings 41.
42 inner race is press-fitted, said bearing 39.40 outer race is installed in a hole provided at the end of the cylindrical projection 4 of the second part of said housing 1.

Further, on the outside of the press-fit portion of the tapered roller bearing 41.42 of the shaft 37.38 having the internal spline, the housing I
The lip portion of the oil seal 43 that is press-fitted is in contact with the lip portion of the oil seal 43 .

The driving force transmission means l11to is an axle shaft shaft 46
and 47, the axle shaft shaft 46.
The spline shaft 48.49 at the end of 47 is connected to the large gear 29.3.
It engages with spline portions 44 and 45 in 0.

A lubricating oil reservoir 50 is provided at the bottom of the second portion 3 of the housing 1, and lubricating oil is stored in the lubricating oil reservoir 50.

The functions and effects of the first embodiment having the above configuration are as follows.

First, when the motor 9.10 is energized, the motor 9.10
The output shaft 11.12 of the output shaft 11.12 rotates, and the pinion gear 18.19 meshing with the output shaft spline rotates. At this time, the rotational reaction force of the output shaft 11.12 applied to the casing of the motor 9.10 acts on the housing 1 of the reduction gear 11°.

The pinion 18.19 is supported by an angular ball bearing 24.25 against the housing l, and the motor 9.1
Rotates without losing zero rotational force. The small gear 1
The large gear 29.30 that meshes with 8.19 is the small gear 18,
The rotation speed is reduced according to the ratio of the pitch diameter to the rotation speed of I9. However, at that time, the force applied to the tooth surface is
Since both the small gears 9.30 and 18.19 are the same, the rotating torque of the large gear 29.30 increases depending on the ratio of the pitch circle diameters.

The rotation of the large gear 29.30 is similar to that of the small gear.
Since it is supported by deep groove ball bearings 39 and 40, it rotates without loss.

The axle shaft 46.47 meshing with the spline portion 44.45 in the large gear 29.30 transmits the rotational speed and rotational torque given by the large gear 29.30 to the wheels.

Here, the operation when moving the vehicle forward will be explained below. At this time, reducer■! . Each motor 9.10 mounted on the motor rotates in the opposite direction when viewed from the respective motor shaft 11.12 side. Here, since the helical gear trains of the left and right small gears I8.19 have different torsion angles, considering the action of force in the axial direction of the gears with the partition wall 5 of the reducer housing 1 as the center, The small gears 18 and 19 or the large gears 29 and 30 are pressed against each other toward the partition wall 5 or toward the outer wall of the housing 1.

In addition, these axial forces are applied to the angular ball bearing 24.2.
5. The tapered roller bearings 41, 42 only hold the bearings, and the motor output shaft 11, 12 that meshes with the small gear 18, 19 is a spline shaft and can move in the axial direction, so the axial force is not applied to the motor 9, 10. Not loaded.

Similarly, no axial forces act on the axle shafts 46,47.

Gear train in housing l (small gear 18, 19, large gear 2
9.30) requires lubrication, and the lubricating oil is supplied from the lubricating oil reservoir 50, and from the large gear 29.30 to the small gear 1.
Splashed on 8.19.

Further, the core portion becomes a mist state due to the rotation of the gear.

These mist is prevented from leaking to the outside by the oil seal 28 between the small gear 18, 19 shaft and the housing 1, or the oil seal 28 between the large gear 29, 30 and the housing 1.

As a result, in the first embodiment, since the motors 9 and 10 are attached to the reducer housing 1, the shaft rotation reaction force is received by the housing 1.

However, in the prior art, since the motor, speed reducer, etc. are attached to the vehicle, the reaction force of the motor is transmitted to the vehicle, which requires high rigidity of the vehicle.

Furthermore, a motor mounting section must be provided on the vehicle. Furthermore, if the motor and reducer are installed separately, it is difficult to align the motor shaft and the reducer small gear shaft, and a shaft joint is usually used. Therefore, in the case of the prior art, that space is required.

On the other hand, in the device of this embodiment, with the above-described configuration, the motor output shaft is spline-coupled within the pinion gear shaft, thereby eliminating the need for a shaft joint and making the device compact. Also, reducer ■8. The gear train located inside has a small pitch diameter and a large pitch diameter in order to obtain a predetermined rotation speed ratio. Additionally, the span of the bearing that supports small gears and large gears is naturally longer.

Therefore, by expanding the bellows of the Daruma-shaped housing and attaching the motor to the concave face, we were able to make it very compact.

Furthermore, helical gear trains have the advantage of being able to transmit a larger force per tooth width than spur gear trains, but have the disadvantage of generating axial force. However, in the device of this embodiment, by symmetrically arranging teeth having different twist angles, the axial force generated on the left and right sides can be canceled out, and the rigidity of the speed reducer housing can be weakened accordingly. Therefore, by making the holes in the partition wall for housing the bearings of the large and small gears large and fan-shaped in the axial direction, it was possible to reduce the weight of the apparatus of the embodiment.

As a result of the above, the device of this embodiment allows the reduction gear and the motor to be integrated, and also makes the device smaller and lighter.

Second Embodiment A two-wheel independent drive system for an automobile according to a second embodiment of the present invention will be explained with reference to FIGS. 7, 8, and 4, focusing on the differences from the first embodiment.

The device of the second embodiment of the present invention has a planetary gear mechanism in order to obtain a larger drive torque, whereas the device of the first embodiment has a set of deceleration means using a large and small gear train 29, 30, 18, 19. A reduction gear is added, and the reduction gear is small and lightweight and can be housed in the housing shown in the first embodiment. The main feature is that it is positioned at an angle of .

As shown in FIGS. 7 and 8, the two-wheel independent drive system for an automobile of this embodiment includes a deceleration means RG2I.

Reducer I2G with RG 22 and housing 51
, an electric motor ■2°, and a driving force transmission means lIr20. Note that FIG. 7 shows the positional relationship when the device of the second embodiment is attached to a vehicle, and FIG. 8 is a sectional view taken along the line A--A in FIG. 4.

This FIG. 8 shows the reduction gear I2°, the electric motor II2°, and the driving force transmission means III2. Since the two-wheel independent drive system for automobiles consisting of the following is a subject matter, the explanation will be centered on the left side portion in FIG.

As shown in FIG. 8, the large gear 52 has a boss shape of the large gear shown in the first embodiment, with a cylindrical hole 53 on one side and a hollow boss shape 54 on the other side. This is an externally toothed spur gear.

The planetary gear mechanism includes a sun gear 55 fixed coaxially with a large gear 52, and a housing 51 located coaxially with the sun gear 55.
It meshes with the ring gear 56 fixed to the ring gear 56 and the sun gear 55 and the ring gear 56, and rotates around the sun gear 55 around the support shaft 76 formed by spline connection with the axle shaft 57 of the driving force transmission means (2). It consists of three planetary gears 59 (the other two are not shown) that revolve.

The shape of the housing 51 is similar to the housing shape of the device of the first embodiment, and the cylindrical protrusion in the axial direction of the second portion 60 corresponding to the belly side has internal teeth that become the ring gear 56 on the inner side of the root. A spur gear is formed. Further, a through hole 6 in the radial direction extends from the inner surface of the hollow cylindrical shaft 63 of the second portion 60, which corresponds to the belly of the partition wall 62, toward the fan-shaped opening 65.
6 is provided in the same number as the fan-shaped openings 65.

A tapered roller bearing 67 is fitted into the hollow cylindrical shaft 63 of the partition wall 62. The rotating shaft 69 has a disk shape at the center and is supported by the tapered roller bearing 67 and a tapered roller bearing 68 in a hole provided at the end of the cylindrical protrusion 61 of the second portion 60 of the housing 51. The housing 51 has a closed hollow cylindrical shape and has an internal spline at one outer end.

The other end of the rotating shaft 69 is a shaft 71 having a hole 70 opened toward the center of the housing 51 and whose outer diameter is precisely finished.
5 Supports the inner diameter. A needle roller bearing 75 that receives a thrust load is provided between the root disk 73 of the rotating shaft 69 and the end surface 74 of the sun gear 55.

A support shaft 76 is provided parallel to the rotating shaft 69 at three equal positions on the outer circumference of the disk 73, and the support shaft 76 is
A planetary gear 59 is rotatably supported via a needle roller bearing 75. The planetary gear 59 is disposed between the sun gear 55 and the ring gear 56 so as to mesh with each other at three equal positions on the circumference, and can revolve on the sun gear 55.

In addition, a rotation detector 78 is fixed to a hole provided in a protrusion 79 of the housing with a bolt 80 at a position that is flush with the surface of the belly portion 60 of the housing and coincides with the right motor shaft. is connected to a shaft 82 protruding from the pinion 81 and a coupling 83.

A thin hole 77 passes through the central hole 70 in the rotating shaft 69 in the inner radial direction of the disk 73 to the center of the support shaft 76, and further passes in the radial direction from the center of the support shaft 76 to the outer diameter surface of the support shaft 76. .

The functions and effects of the second embodiment having the above configuration are as follows.

First, when the large gear 52 is rotated, the sun gear 55 integrated with the large gear 52 is driven. Here, the thrust force generated by the helical gears of the large gear 52 is applied to the angular ball bearing 39 provided in the middle of the partition wall 62 or the sun gear 55.
Thrust needle roller bearing 75 and disk 73 on the end face of
The housing 51 is supported by a conical roller bearing 68 outside the housing 51, which supports a rotating shaft 69 through the housing 51.

On the other hand, the planetary gear 59 that is engaged with the rotation of the sun gear 55 is connected to the ring gear 59 fixed to the housing 51.
Since it also meshes with the ring gear 56, it revolves around the inner circumference of the ring gear 56. Therefore, the support shaft 76 that supports the planetary gear 59 drives the disk 73, and as a result, the rotating shaft 69 is rotated.

Due to this rotation of the rotating shaft 69, the air in the small hole 77 in the disk 73 is sent into the support shaft 76 by centrifugal force. Therefore, the mist oil scattered from the lubricating oil reservoir 78 by the large gear 52 is transferred from the center of the rotating shaft 69 to the planetary gear 59.
is supplied into a needle roller bearing 75 that rotatably supports the.

Furthermore, the rotation of the rotating shaft 69 drives the axle shaft 57 that engages with the internal spline.

Therefore, the driving torque of the large gear 52 increases in accordance with the reduction ratio of the planetary gear, and acts as a driving torque of the axle shaft 57.

Further, the rotation detector 78, which is connected by a coupling 83 to a small gear spline-coupled to the motor output shaft, rotates in synchronization with the motor.

As described above, the two-wheel independent drive system for an automobile according to the second embodiment includes the reduction gear (2). Since the planetary gear mechanism can be housed in the housing protrusion of the device of the first embodiment, the physique of the first embodiment does not change and the weight does not increase significantly (compared to the device of the first embodiment). Output shaft torque can be increased.

In addition, the device of this embodiment makes it possible to supply oil to the bearings of the planetary gears in the planetary gear mechanism by a pump action using centrifugal force, so that the temperature rise of the speed reduction means can be equalized without the need for a special lubricating device. By reducing this, local temperature increases can be effectively suppressed.

Furthermore, the motor was installed in a position with a predetermined angle around the large gear shaft, allowing for the most efficient and optimal placement in the triangular position formed by the vehicle's frame BF shape and the ground. Therefore, the influence of heat generation in the gear meshing portion can be dispersed, and it is also possible to easily attach a rotation detector for controlling the motor rotation speed.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing the concept of the first invention, FIG. 2 is a schematic configuration diagram showing the concept of the third invention, and FIG. 3 is a schematic configuration diagram showing a specific example of the mounting position of the prime mover of the present invention. FIG. 4 is a schematic configuration diagram showing another specific example of the mounting position of the prime mover of the present invention;
5 and 6 show a first embodiment of the present invention, and FIG.
The figure is a schematic diagram showing the entire structure, Figure 6 is a schematic diagram of the entire structure,
7 and 8 show a second embodiment of the present invention, and FIG.
The figure is a schematic configuration diagram 1 showing the installation position relationship on the vehicle.
FIG. 8 is a schematic diagram showing the entire structure. I,,I,,1. . , I2゜...Reducer III, U
2,lll01I[3Q'''Electric motor I[11,llI
2, ll11G, ll12G...driving force transmission means S
G,,SG2,SG,,SG4,SG5,SG,,SG
,,SG,...small gear

Claims (2)

[Claims] (1) A two-wheel independent drive system for an automobile in which the drive wheels of a vehicle are driven by separate electric motors, which comprises a first small gear and a first large gear meshed with the first small gear; a first reduction gear train having an input shaft on one surface of the first small gear and an output shaft on one surface of the first large gear; and a second reduction gear train arranged parallel to the first small gear. a small gear and a second large gear meshed with the second small gear, and the input shaft of the second small gear is on the surface opposite to the surface having the input/output shaft of the first reduction gear train. a reduction means comprising a second reduction gear train having an output shaft of a second large gear; a partition wall to which bearings that rotatably support the respective gears are fixed; and the first reduction gear partitioned by the partition wall; A housing consisting of a first chamber and a second chamber that house a first gear train and a second reduction gear train, respectively, and a lubricating oil reservoir provided at the bottom of the first and second chambers. a pair of electric motors whose output shafts are connected to respective input shafts of the first and second small gears of the first and second reduction gear trains; and the first and second reduction gears of the reduction means. A two-wheel independent drive system for an automobile, characterized in that it comprises a driving force transmitting means connected to each output shaft of the second large gear and transmitting the driving force from the deceleration means to the respective driving wheels of the vehicle. . (2) The electric motor is arranged such that the electric motor on the first reduction gear train side and the electric motor on the second reduction gear train side form an angle of 120 degrees to 150 degrees in circumferential angle around the large gear shaft of the reduction gear. 2. The two-wheel independent drive system for a motor vehicle according to claim 1, further comprising a motor rotation speed detector disposed within a range and facing each of the motors.