JP2019043275A - Vehicle drive device - Google Patents

Abstract

To provide a vehicle drive device which can correspond to various vehicle ranks and can assure reliability of a motor.SOLUTION: This vehicle drive device includes: an axle housing 21 to which a differential side housing 13a is connected, and which integrally accommodates a drive shaft 23; a first support part 29a which connects a first rotary support shaft 27b connected to a vehicle body 3 and the axle housing, is oscillatorily moved around the first rotary support shaft, and supports the axle housing on the vehicle body; and a second support part 29b which connects a second rotary support shaft 37 supported on the vehicle body via a rail structure 31 and a motor side housing 13b, is oscillatorily moved around the second rotary support shaft, and supports the motor side housing on the vehicle body. The second rotary support shaft is accommodated in a sliding block body of a rail groove of the rail structure, and the second rotary support shaft becomes movable in a vehicle longitudinal direction.SELECTED DRAWING: Figure 1

Description

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

  Conventionally, as a drive device for vehicles, a drive unit in which a drive motor and a reduction gear are integrally provided to a differential gear is known (see, for example, Patent Document 1).

International Publication No. 2014/148410

  In commercial vehicles such as trucks, there are various car models for each vehicle specification, and the width of the vehicle on which the drive device can be mounted is also various according to the car models. As an axle structure compatible with such various types of vehicles, there is a rigid axle structure using an axle housing for storing an axle.

  However, in such a rigid axle structure, when the drive unit described above is mounted, all the drive units together with the axle housing serve as an unsprung support, so the vibration input to the motor mounted on the drive unit becomes large. Reliability may be reduced.

  Therefore, an object of the present invention is to provide a drive device for a vehicle that can cope with various vehicle types and can ensure the reliability of the motor.

  The present invention can be realized as the following application example. The vehicle drive device according to this application example integrally includes a motor for driving the vehicle, a reduction gear connected to the motor, and a differential gear connected to the reduction gear to transmit the driving force of the motor to the drive wheels of the vehicle. A drive unit for a vehicle comprising a drive unit housing, the differential housing of the drive unit housing being connected, an axle housing integrally housing a drive shaft of a drive wheel, and a first connected to a vehicle body of the vehicle A first support portion for supporting the axle housing on the vehicle body by connecting the rotation support shaft and the axle housing and swingingly moving about the first rotation support shaft as a rotation center and supporting the vehicle body of the vehicle via a rail structure The second rotation support shaft and the motor side housing of the drive unit housing, and the second And a second support portion for supporting the motor side housing to the vehicle body by rocking movement, and the rail structure is configured such that the second rotation support shaft is accommodated in the sliding block body accommodated in the rail groove The second rotation support shaft is configured to be movable in the vehicle longitudinal direction.

  With the same configuration, for example, when the axle housing elastically connected to the first support portion and the second support portion is displaced over the road surface protrusion or the like during traveling of the vehicle, the drive housing is input to the drive unit housing The impact or load to be absorbed is absorbed by the peristaltic movement of the drive unit housing in response to the vertical displacement of the axle housing.

  That is, in the drive unit housing in which the respective devices are integrally housed, the differential side housing with the axle housing is displaced in the vertical direction according to the displacement of the axle housing in the vertical direction and is connected to the second support rotary shaft The sliding block body provided on the second rotation support shaft of the motor side housing slides (moves) in the longitudinal direction of the vehicle on the rail structure, resulting in a peristaltic motion about the second support rotation shaft as a rotation center.

  The peristaltic movement of the drive unit housing relieves the shock and load input to the drive unit housing, thereby protecting each device including the motor integrally attached to the drive unit housing from the applied shock and load. Here, since the drive unit housing structure adopting the rigid axle is relatively heavy, stress in the vehicle longitudinal direction is generated in the second support rotary shaft coupled to the motor side housing of the drive unit housing during peristaltic movement. Do. This may reduce the reliability of the motor. However, by adopting a configuration in which the second rotary support shaft is movable in the longitudinal direction of the vehicle in the rail structure accommodating such a sliding block, stress in the longitudinal direction of the vehicle on the second support rotational shaft is relieved. It is possible to secure the reliability of the motor. From the above, such a vehicle drive device can not only be compatible with various vehicle models by adopting a rigid axle, but also can sufficiently ensure the reliability of the motor.

  In addition, since the sliding block slides smoothly in the rail grooves of the rail structure, the generation of noise can be suppressed. Moreover, by means of the sliding block, it is possible to sufficiently withstand the impact and load applied.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the drive device for vehicles by which the aspect which concerns on one Embodiment of this invention was assembled | attached to the vehicle. The side view of the drive device for vehicles seen from arrow A in FIG. Sectional drawing which shows the structure of the rail structure circumference which follows the BB line in FIG. The disassembled perspective view which disassembled a part of the same rail structure.

Hereinafter, the present invention will be described based on an embodiment shown in FIGS. 1 to 4.
FIG. 1 shows the lower part of the rear of an electric vehicle (hereinafter referred to as a vehicle) such as a commercial vehicle such as a truck. Incidentally, the X direction in FIG. 1 indicates the vehicle longitudinal direction, and the Y direction indicates the vehicle width direction.

  The lower structure of the electric vehicle will be described. A member 1 in FIG. 1 is a frame that constitutes a chassis. The frame 1 is configured in a ladder shape from a pair of side rails 3 in the vehicle longitudinal direction and a plurality of cross members (not shown) provided between the pair of side rails 3.

  A drum brake 5 and driving wheels 7 (only one side shown by a two-dot chain line) mounted on the drum brake 5 and the drum brake 5 are disposed on both sides of the side rail 3 in the vehicle width direction. Further, spring members, for example, leaf springs 9 extending in the longitudinal direction of the vehicle are disposed directly under the side rails 3 respectively. Incidentally, both ends of the leaf spring 9 have cylindrical portions 9a with bushes (not shown). In addition, a drive device 11 (corresponding to a vehicle drive device according to the present application) serving as a drive system of the electric vehicle is disposed between the rear portions of the side rails 3.

  The drive device 11 is configured as a drive unit 11 a by integrally assembling the devices of the drive system. Specifically, the drive unit 11a has a box-shaped unit housing 13 (corresponding to the drive unit housing of the present application) extending in the longitudinal direction of the vehicle, and the front side of the unit housing 13 (the longitudinal direction of the vehicle) The motor 15 for driving the motor is assembled sideways, the reduction gear 17 is accommodated in the longitudinal middle portion of the unit housing 13, and the differential gear 19 is accommodated in the rear side (vehicle longitudinal direction) of the unit housing 13. That is, the unit housing 13 includes the motor 15, the reduction gear 17, and the differential gear 19.

  A cylindrical pair of axle housings 21 is connected to both sides of the differential side housing 13 a of the unit housing 13. The axle housing 21 is connected to the drum brake 5. A drive shaft 23 is rotatably accommodated in the interior of the axle housing 21, and the drive shaft 23 is integrally housed and supported in the axle housing 21. The drive shaft 23 movably connects between left and right output portions (not shown) of the differential gear 19 and the wheel mounting portion 5 a of the drum brake 5, and the driving force output from the differential gear 19 is a drive wheel It is structured to be transmitted to 7.

  Further, an input portion (not shown) of the reduction gear 17 is movably connected to a motor shaft 15a of the motor 15, specifically to a motor shaft 15a attached to the rotor 15c. An output portion (not shown) of the reduction gear 17 is movably connected to an input portion (not shown) of the differential gear 19, and a driving force output from the motor 15 is transmitted to the differential gear 19 through the reduction gear 17. It is distributed from the differential gear 19 to the left and right drive shafts 23. That is, the drive unit 11a transmits the drive force of the motor 15 to the left and right drive wheels 7.

  The drive unit 11a (drive device 11) is supported by the side rail 3 which is a vehicle body, using a suspension device 25 using left and right leaf springs 9. In the vehicle drive device according to the present embodiment, the support structure is devised. Each part of this support structure is a side view of FIG. 2 (arrow A in FIG. 1), a sectional view of FIG. 3 (B-B line in FIG. 2), and an exploded perspective view of FIGS. Each is shown in the figure.

  Referring to FIGS. 2 to 4, the drive unit 11a is disposed between the side rails 3 in a diagonal posture in the vehicle longitudinal direction with the differential side on the lower side and the motor side on the upper side.

  Then, an axle housing 21 protruding from the differential side housing 13a of the drive unit 11a is supported at the central portion in the longitudinal direction of the left and right leaf springs 9. For example, the axle housing 21 is supported by the leaf spring 9 using a saddle member and a U-shaped bolt (both not shown).

An end on the rear side (vehicle longitudinal direction) of each leaf spring 9 is supported by the lower portion of the side rail 3 (vehicle body) via a link mechanism 27.
Specifically, the link mechanism 27 is configured by a mechanism capable of extending and contracting in the vertical direction. For example, the link mechanism 27 can be pivoted via, for example, two sheet metal members 27a held at a predetermined distance extending downward from the side rail 3, a lower portion of the sheet metal member 27, and the connection pin 27b. It consists of two sheet metal members 27c to be supported. The cylindrical portion 9a on the rear side of the leaf spring 9 is interposed in the lower part between the sheet metal members 27a.

  A pin member 27d (corresponding to the first rotation support shaft of the present application) is inserted into the two sheet metal members 27c and the cylindrical portion 9a so as to intersect them, and a shackle link for supporting the end of the leaf spring 9 is formed. ing. That is, the pin member 27d constitutes a first support portion 29a that rotatably supports the cylindrical portion 9a of the leaf spring 9 with respect to the side rail 3 (vehicle body).

  The front end (vehicle longitudinal direction) end of the leaf spring 9 is rotatably supported by a bracket 30 mounted on the lower part of the side rail 3 opposite to the link mechanism 27 across the axle housing 21. There is. Specifically, the bracket 30 is composed of two sheet metal members. A cylindrical portion 9a on the front side of the leaf spring 9 is interposed between two sheet metal members. Then, the pin member 30a (corresponding to the first rotation support shaft of the present application) is inserted so as to intersect the bracket 30 and the cylindrical portion 9a, and the cylindrical portion 9a of the leaf spring 9 is a side rail as in the rear side. A first support portion 29a rotatably supported by 3 (the vehicle body) is configured.

  A pair of rail structures 31 is installed at the lower part of each side frame 3 between the bracket 30 and the axle housing 21. The motor housing 13 b of the drive unit 11 a is supported by the rail structure 31.

  This support structure is described with reference to FIGS. 3 and 4. First, the rail structure 31 will be described. For example, the rail structure 31 is accommodated in a substantially C-shaped rail groove 32a formed by the rail groove 32 having a substantially C-shaped cross section and the same rail groove 32. A sliding block body 33 and a circular bearing 35 built in the sliding block body 33 are provided.

  The rail groove 32 has a predetermined length in the X direction. Each rail groove body 32 is disposed on both sides in the vehicle width direction of the motor side housing 13b (including the motor 15) of the drive unit 11a so that the openings face inward and extend in the vehicle longitudinal direction. These rail groove bodies 32 are attached to the lower part of the plate-like brackets 36 which project downward from the side rails 3 in a predetermined manner. Here, the rail groove body 32 is disposed in the same direction as the side rail 3 at a point on the outer side in the vehicle width direction from the side rail 3.

  The sliding block body 33 is a synthetic resin block that can slide smoothly in the rail groove 32a, for example, a nylon block whose surface is coated with a rubber as a lubricant. Incidentally, a through hole 33a for assembly is provided on the side of the block facing the side opening of the rail groove 32 (FIG. 4 (b)).

  For the circular bearing 35, for example, two rows of roller bearings in which a plurality of rollers 35c are interposed between a circular inner race 35a and an outer race 35b are used. The outer race 35 b of the roller bearing is press-fit into the through hole 33 a of the sliding block 33, and the circular bearing 35 is incorporated in the sliding block 33.

  On the other hand, as shown in FIG. 1, from the housing portion on the motor side which is both sides of the motor side housing 13b (drive unit 11a) and the end wall of the motor housing 15b forming the outer shell of the motor 15, support shafts 37 are provided. (It corresponds to the 2nd rotation support axis of this application) is protrudingly provided. The support shaft 37 extending in the left-right direction (the vehicle width direction) has a length that reaches the left and right rail grooves 32. The support shafts 37 may protrude to both sides from substantially the same position as the rotation center of the motor shaft 15 a of the motor 15. That is, the support shaft 37 can be provided at a position substantially coinciding with the rotation center of the motor 15.

  The distal end of each support shaft 37 is attached to a circular bearing 35 of a sliding block 33 housed in the rail groove 32. Specifically, the tip end portion of the support shaft 37 is inserted into the inner race 35a of the circular bearing 35 (press fit), and the motor side housing 13b is rotatable relative to the side rail 3 (vehicle body) and movable in the longitudinal direction. The second support portion 29b is configured.

  As a result, when traveling over a protrusion on the road surface α or the like, the entire drive unit 11a is pivotally moved about the support shaft 37 with the differential side housing 13a including the axle housing 21 as the movable side.

  Specifically, the leaf spring 9 elastically supports the axle housing 21 with the pin members 27d and 30a as fixed fulcrums and the rail groove 32 and the sliding block 33 (including the circular bearing 35) as movable fulcrums. That is, the axle housing 21 is elastically supported with the behavior that the movable fulcrum is displaced in the longitudinal direction of the vehicle. In conjunction with the vertical movement of the axle housing 21, the drive unit 11a is slidingly displaced with the circular bearing 35 and the support shaft 37 as a peristaltic center, and a sliding block where the change of the fulcrum position of the circular bearing 35 generated at that time slides Absorbed by body 33

  That is, from the axle rigid structure configured by combining the first support portion 29a, the second support portion 29b, the rail structure 31, and the sliding block body 33, the drive unit 11a is able to make a peristaltic movement, and an axle as much as possible to the drive unit 11a. The impact and load transmitted from the housing 21 are not applied. Incidentally, the shock absorber attached to the drive unit 11a is omitted.

Below, an effect | action of the drive device 11 comprised in this way is demonstrated.
The traveling of the vehicle is performed by the operation of the motor 15. That is, the driving force generated by the motor 15 is transmitted to the differential gear 19 through the reduction gear 17. Then, it is transmitted from the differential gear 19 to the left and right driving wheels 7 through the left and right drive shafts 23, and the vehicle travels on the road surface α.

When a projection (not shown) such as a stone is present on the road surface α, the leaf spring 9 is displaced upward or the leaf spring 9 itself is elastically deformed upward, and the drive wheel 7 rides over the projection.
The impact and load accompanying the crossing over of the protrusion are input from the axle housing 21 to the differential side housing 13a disposed diagonally below the drive unit 11a.

  At this time, the motor-side housing 13b disposed diagonally above the drive unit 11a is connected to the sliding block 33 (including the circular bearing 35) in the rail groove 32 via the support shaft 37, and the rotation direction, vehicle It is supported displaceably in the front and rear direction. For this reason, in the entire drive unit 11a, the differential side housing 13a is peristaltically displaced upward or downward with the motor side housing 13b as a peristaltic center. An arrow s in FIG. 2 indicates a peristaltic trajectory of the drive unit 11a at this time.

The inner race 35a of the circular bearing 35 is rotated with the swinging of the drive unit 11a, or the sliding block 33 is displaced on the rail groove 32 in the front-rear direction. An arrow t in FIG. 2 indicates the direction in which the sliding block body 33 is displaced.
Then, the entire drive unit 11a performs a peristaltic motion with the sliding block 33, the circular bearing 35, and the support shaft 37 as a peristaltic fulcrum.

  As a result, the shock and load input from the axle housing 21 to the drive unit 11a are released (absorbed) by the peristaltic movement of the drive unit 11a that is generated along with the vertical displacement of the axle housing 21.

  That is, since the drive unit 11a (drive unit housing structure) adopting the rigid axle has a relatively large weight, the support shaft 37 connected with the motor side housing 13b of the drive unit housing 13 during the peristaltic movement is in the vehicle longitudinal direction Stress occurs. As a result, the reliability of the motor 15 may be reduced. However, in the rail structure 31 of the drive device 11 (vehicle drive device), the support shaft 37 is movable in the vehicle longitudinal direction, so that the stress in the vehicle longitudinal direction is relieved by the support shaft 37. The reliability of the motor 15 can be secured.

  Therefore, such a driving device 11 (driving device for a vehicle) can not only cope with various vehicle models by adopting a rigid axle, but also can sufficiently ensure the reliability of the motor 15.

  Moreover, since the peristaltic movement of the drive unit 11a is smoothly performed by the sliding block body 33 sliding in the rail groove 32a of the rail groove 32 (rail structure 31), the generation of noise is suppressed. In addition, by means of the sliding block 33, it is possible to sufficiently withstand an impact or load applied. In addition, the rail structure 31 providing such an effect is simple because it can be a structure in which the rail groove 32 and the sliding block 33 are combined with the support shaft 37.

  In addition, when the support shaft 37 and the rotation center of the motor 15 coincide with each other, it is possible to more effectively reduce the impact and load input to the motor 15 (drive unit 11a).

  The present invention is not limited to the above-described embodiment, and various changes may be made without departing from the scope of the present invention. For example, although the example using a sliding block object made of a synthetic resin was mentioned in one embodiment, not only this but as long as it can carry out slide displacement inside the rail groove smoothly, it may be what kind of parts. In one embodiment, although the rail groove body is disposed on the outer side in the vehicle width direction from the side rail, the invention is not limited thereto. The rail groove body may be disposed on the inner side in the vehicle width direction from the side rail. You may arrange it inside. Of course, although the present invention is applied to an electric commercial vehicle, the present invention is not limited to this, and may be applied to various vehicles including passenger cars.

3 Side rail (body)
7 Drive Wheel 9 Leaf Spring 11 Drive Device (Drive Device for Vehicle)
13 Unit housing (drive unit housing)
13a Differential side housing 13b Motor side housing 15 Motor 17 Reduction gear 19 Differential gear 21 Axle housing 23 Drive shaft 27d, 30a Pin member (1st rotation support shaft)
29a first support portion 29b second support portion 31 rail structure 32 rail groove 32a rail groove 33 sliding block 35 circular bearing 37 support shaft (second rotation support shaft)

Claims (1)

A drive unit housing integrally containing a motor for driving a vehicle, a reduction gear connected to the motor, and a differential gear connected to the reduction gear and transmitting the driving force of the motor to the drive wheels of the vehicle A vehicle drive device comprising:
An axle housing to which a differential side housing of the drive unit housing is connected and which integrally accommodates a drive shaft of the drive wheel;
A first rotation support shaft connected to a vehicle body of the vehicle and the axle housing are elastically connected, and the axle housing is supported on the vehicle body by swinging movement with the first rotation support shaft as a rotation center A first support,
The second rotary support shaft supported by the vehicle body of the vehicle via a rail structure is connected to the motor side housing of the drive unit housing, and is pivoted about the second rotary support shaft as a rotation center. A second support portion for supporting a motor side housing on the vehicle body;
Including
The rail structure is configured such that the second rotary support shaft is movable in the longitudinal direction of the vehicle by housing the second rotary support shaft in a sliding block body housed in a rail groove. The drive device for vehicles characterized by the above.

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