JP2006199144A - Driving device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten an axial dimension of the whole driving device for a vehicle by devising disposition and structure of a parking brake device. <P>SOLUTION: The driving device 1 is equipped with a housing 2, an electric motor 3, a driving shaft 33 extending from the electric motor 3, a speed reduction device 4 which is coaxially disposed on the driving shaft 33 for reducing the rotation of the driving shaft 33, and the parking brake device 100 for braking the rotation of the driving shaft 33. The speed reduction device 4 includes a connecting member 110 rotating by a torque transmitted from the driving shaft 33. The parking brake device 100 has an annular friction connecting part 120 for braking the relative rotation relative to the housing 2 of the connecting member 110 by friction engagement, and a parking brake operation mechanism 130 which imparts the axial energizing force relative to the friction connecting part 120 for frictionally engaging the friction connecting part 120. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle drive device, and more particularly to a vehicle drive device including a parking brake device.

In recent years, as a brake device for a special work vehicle such as a forklift, a wet brake device considering long life and sealing performance is being adopted instead of a dry brake device. The wet brake device includes, for example, a brake housing disposed on the outer peripheral side of the axle shaft, a friction coupling portion for braking relative rotation of the axle shaft with respect to the brake housing by friction engagement, and an axial direction with respect to the friction coupling portion. A parking brake operating mechanism and a service brake operating mechanism for applying the urging force and frictionally engaging the friction coupling portion. Since this wet brake device is intended to extend the life of a portion where the brake housing is filled with hydraulic oil and frictionally engaged, the friction coefficient at the friction coupling portion is lower than that of the dry brake device. Therefore, the friction coupling portion of the wet brake device secures the braking force against the axle shaft by increasing the number of friction surfaces by using a plurality of annular friction disks or increasing the biasing force against the friction coupling portion (for example, , See Patent Document 1).
JP 2003-247573 A

  In the parking brake operating mechanism of the wet brake device described above, the biasing force in the axial direction to the friction connecting portion is released by supplying the hydraulic pressure, the supply of hydraulic pressure is stopped, and the biasing force in the axial direction is applied to the friction connecting portion. This is a so-called negative brake that generates braking force. Therefore, the braking force at the time of parking is ensured by a plurality of coil springs arranged in the circumferential direction instead of hydraulic pressure (see, for example, FIG. 1 of Patent Document 1). However, if the braking force is secured by the coil spring as described above, the coil spring becomes large, and the accommodation space for the coil spring becomes large. Further, since the urging force by the coil spring is not enough, it is necessary to increase the number of friction surfaces of the friction disk to ensure the braking force, and the accommodation space of the friction coupling portion is increased. As described above, when the coil spring is used to secure the braking force during parking, the axial dimension of the wet brake device is increased, and the axial dimension of the vehicle drive device is also increased.

  The subject of this invention is shortening the axial direction dimension of the whole drive device of a vehicle by devising arrangement | positioning and structure of a parking brake apparatus.

  The drive device according to claim 1 is for running the vehicle. The drive device includes a housing, a power generator, a drive shaft extending from the power generator, a speed reduction device that is arranged coaxially with the drive shaft and decelerates the rotation of the drive shaft, and brakes the rotation of the drive shaft. And a parking brake device. The reduction gear includes a connecting member that is rotated by torque transmitted from the drive shaft. The parking brake device frictionally engages the friction coupling portion by applying an axial biasing force to the friction coupling portion and an annular friction coupling portion for braking relative rotation of the coupling member with respect to the housing by friction engagement. And a parking brake operating mechanism.

  Since this drive device can brake the rotation of the connecting member included in the speed reducer, it is possible to adjust the speed reduction ratio of the speed reducer compared to the conventional case where a parking brake device is provided around the drive wheel. The braking force required to maintain the parking state can be reduced, and the friction surface of the parking brake device can be reduced. Thereby, the axial direction dimension of a parking brake apparatus can be shortened, and the axial direction dimension of the whole drive device can be shortened.

  According to a second aspect of the present invention, there is provided the driving device according to the first aspect, wherein the parking brake actuating mechanism is disposed in the vicinity of the friction coupling portion and the pressing member is urged in the axial direction against the friction coupling portion. An annular urging member and an annular piston for releasing the urging force of the urging member by hydraulic pressure.

  Since this drive device uses an annular urging member, the axial dimension of the parking brake device can be shortened as compared with the conventional case where a coil spring is used. Thereby, the axial direction dimension of a drive device can be shortened.

  The drive device according to claim 3 is the drive device according to claim 1 or 2, wherein the reduction device further reduces the rotation output from the first reduction device and the first reduction device for reducing the rotation of the drive shaft. A second reduction gear. The first reduction gear is provided to connect a plurality of first planetary gears that mesh with the outer peripheral side of the drive shaft, an annular first ring gear that is provided on the outer peripheral side so as to mesh with the first planetary gear, and a plurality of first planetary gears. And an annular connecting member.

  In this drive device, the rotation of the drive shaft can be braked by the first speed reducer provided on the upstream side of the speed reducer. Therefore, compared to the conventional case where a brake device is provided around the drive wheel, parking is performed. The braking force required to maintain the state can be reduced. Thereby, the axial direction dimension of a parking brake apparatus can be shortened, and the axial direction dimension of the whole drive device can be shortened.

  According to a fourth aspect of the present invention, in the drive device according to the second or third aspect, an annular support member extending between the power generator and the speed reducer is fixed to the housing. The urging member has an annular portion that urges the pressing member, and a plurality of lever portions that protrude radially inward from the annular portion. The parking brake operating mechanism is disposed between the lever portions on the inner peripheral side of the annular portion, and a plurality of the parking brake operating mechanisms are connected to the support member so as to be elastically deformable in the axial direction and not to be relatively rotatable. The fixing member is further provided.

  In this drive device, the annular portion on the outer peripheral side of the biasing member biases the pressing member, and the inner peripheral side of the annular portion is fixed by the fixing member. By adjusting the position (fulcrum) of the fixing member, it is possible to apply a large urging force while shortening the axial dimension as compared with the conventional case where a coil spring is used. For example, comparing the case where the distance between the fulcrum and the action point is long and the case where the distance between the fulcrum and the action point is long in the same urging member, the urging force acting on the action point is greater when the distance is short. As a result, the number of friction surfaces of the friction coupling portion can be reduced, and the axial dimension of the friction coupling portion can be shortened. Thereby, the axial direction dimension of a parking brake apparatus can be shortened, and the axial direction dimension of the whole drive device can be shortened.

  According to a fifth aspect of the present invention, in any one of the second to fourth aspects, the piston can bias the inner peripheral end of the lever portion in the axial direction.

  In this drive device, since the piston can urge the inner peripheral end of the lever portion in the axial direction, a so-called negative brake can be easily realized.

  According to a sixth aspect of the present invention, in any one of the second to fifth aspects, the urging member is constituted by a plurality of plate members.

  In this drive device, since the urging member is composed of a plurality of plate members, a larger urging force can be generated by increasing the number of plate members, the friction surface can be reduced, and the parking brake The axial dimension of the device can be shortened.

  According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the friction coupling portion is disposed on the outer peripheral side of the coupling member.

  In this drive device, since the friction coupling portion is disposed on the outer peripheral side of the coupling member, the axial dimension of the parking brake device can be shortened.

  A drive device according to an eighth aspect of the present invention is the drive device according to any one of the first to seventh aspects, wherein the friction coupling portion is engaged with the housing so as not to be relatively rotatable and to be relatively movable in the axial direction. The disc and a plurality of annular second friction discs engaged with the outer peripheral portion of the connecting member so as not to rotate relative to each other and to be relatively movable in the axial direction.

  According to a ninth aspect of the present invention, in any one of the fourth to eighth aspects, the support member includes a thrust bearing that supports the connecting member so as to be relatively rotatable and receives an axial load from the connecting member.

  In this drive device, since the support member has a thrust bearing, the rotational motion of the connecting member is stabilized.

  In the vehicle drive device according to the present invention, the parking brake device is arranged on the upstream side of the speed reduction device, and the annular urging member is used, whereby the axial dimension of the entire drive device can be shortened.

An embodiment of the present invention will be described with reference to the drawings.
1. Overall Configuration of Driving Device FIG. 1 is a sectional view of a driving device as a first embodiment of the present invention. The drive device 1 includes a housing 2, an electric motor 3 (power generator), a speed reducer 4, a differential device 5, a pair of axles 6, a pair of wet brake devices 7, a pair of drive wheels 8, The parking brake device 100 is configured. The electric motor 3, the reduction gear 4, and the differential device 5 are accommodated in the housing 2. The electric motor 3 is, for example, an SR motor (Switched Reluctance Motor) or the like, and is fixed inside the housing 2. The reduction gear 4 is for reducing the rotation output from the electric motor 3 and is connected to the output side of the electric motor 3. The differential device 5 is for separately transmitting the rotation output from the reduction gear 4 to the left and right drive wheels 8 and for adjusting the rotational difference of the drive wheels 8, and is connected to the output side of the reduction gear 4. ing. The axle 6 is for supporting the drive wheel 8 so as to be rotatable relative to the housing 2 while transmitting the rotation output from the differential device 5 to the left and right drive wheels 8. It is arrange | positioned so that it may extend. A wet brake device 7 for braking the rotation transmitted from the axle 6 to the drive wheel 8 is provided on the outer peripheral side of the axle 6. Further, a parking brake device 100 for braking the rotation of the drive shaft is provided between the electric motor 3 and the reduction gear 4.

2. FIG. 2 shows a cross-sectional view around the reduction gear. Hereinafter, the configuration of each unit will be described in detail with reference to FIG.

(1) Electric motor The electric motor 3 includes a stator 31, a rotor 32, and a drive shaft 33. The stator 31 is a cylindrical member provided on the outer peripheral side, and is fixed to the housing 2. A cylindrical rotor 32 is disposed on the inner peripheral side of the stator 31 so as to be relatively rotatable. A cylindrical drive shaft 33 extending in the axial direction is fixed to the inner peripheral side of the rotor 32 so as not to be relatively rotatable. An annular motor cover 35 (support member) fixed to the housing 2 is provided on the speed reduction device 4 side of the electric motor 3. The motor cover 35 is for partitioning the space between the electric motor 3 side and the speed reduction device 4 and the differential device 5 side, and the space on the speed reduction device 4 side is filled with hydraulic oil. A hydraulic plug 101 is connected to the motor cover 35, and an oil passage 102 communicating with a parking hydraulic chamber 136 described later is formed inside.

(2) Reduction gear The reduction gear 4 is mainly composed of a first reduction gear 40 and a second reduction gear 44. The first reduction gear device 40 is for reducing the rotation of the drive shaft 33 of the electric motor 3, and mainly includes a plurality of first planetary gears 41, a first ring gear 45, and a first carrier 42. .

  The first planetary gear 41 is disposed circumferentially on the outer peripheral side of the drive shaft 33 and meshes with an input sun gear 33 a provided on the outer peripheral side of the end of the drive shaft 33. The first ring gear 45 is an annular member provided on the outer peripheral side of the plurality of first planetary gears 41 and meshes with the first planetary gear 41. The first ring gear 45 is fixed to the housing 2. The first carrier 42 is an annular member for connecting a plurality of first pins 41 a respectively provided in the first planetary gear 41 in the circumferential direction. On the opposite side of the first planetary gear 41 from the first carrier 42, a connecting member 110 constituting a parking brake device 100 described later is provided. The connecting member 110 is an annular member for connecting the plurality of first pins 41a in the circumferential direction, and the friction connecting portion 120 of the parking brake device 100 is provided on the outer peripheral side. A first sun gear 43 extending in the axial direction is fixed to the inner peripheral side of the first carrier 42.

  The second reduction gear 44 is for further reducing the rotation output from the first reduction gear 40, and mainly comprises a plurality of second planetary gears 46, a second ring gear 48, and a second carrier 47. Has been.

  The second planetary gear 46 is provided on the outer peripheral side of the first sun gear 43 of the first reduction gear 40 and meshes with the first sun gear 43. The second ring gear 48 is an annular member provided on the outer peripheral side of the plurality of second planetary gears 46 and meshes with the second planetary gears 46. The second ring gear 48 is fixed to the housing 2. The second carrier 47 is an annular member for connecting a plurality of second pins 46 a respectively provided in the second planetary gear 46 in the circumferential direction.

(3) Differential Device The differential device 5 mainly includes a third ring gear 54, a plurality of third planetary gears 53, a third carrier 51, a third sun gear 52, and a fourth carrier 56. Yes.

  The third ring gear 54 is a cylindrical member fixed to the outer peripheral side of the second carrier 47 of the second reduction gear 44. The third planetary gear 53 is arranged in the circumferential direction so as to mesh with the inner peripheral side of the third ring gear 54. The third carrier 51 is an annular member for connecting a plurality of third pins 53 a respectively provided in the third planetary gear 53 in the circumferential direction. The third carrier 51 is connected to the second carrier 47 by the first bearing 55. It is supported for relative rotation. The third sun gear 52 is disposed on the inner peripheral side of the plurality of third planetary gears 53 and meshes with the third planetary gears 53. The third sun gear 52 is fixed to the outer peripheral side of the second axle shaft 62. Further, on the opposite side of the third planetary gear 53 from the third carrier 51, a fourth carrier 56 is provided so as to connect the plurality of third pins 53a in the circumferential direction. The fourth carrier 56 is fixed to the outer peripheral side of the first axle shaft 61 and is supported by the second bearing 63 so as to be relatively rotatable with respect to the first support member 64 fixed to the housing 2.

3. FIG. 3 is a cross-sectional view of the vicinity of the parking brake device according to the first embodiment of the present invention. In FIG. 3, the electric motor 3 is arranged on the left side. Hereinafter, the configuration of each unit will be described in detail with reference to FIG.

  The parking brake device 100 includes a connecting member 110, a friction connecting portion 120, and a parking brake operating mechanism 130.

(1) Connecting member As described above, the connecting member 110 is an annular member for connecting the plurality of first pins 41a in the circumferential direction, and a friction connecting portion 120 described later is provided on the outer peripheral side. . A cover member 36 is fixed to the motor cover 35. The inner peripheral portion of the connecting member 110 is restricted from moving toward the axial motor 3 (left side in FIG. 3) by a thrust bearing 35 a provided on the cover member 36. A plurality of second external teeth 111 that are arranged in the circumferential direction, protrude outward in the radial direction, and extend in the axial direction are formed on the outer peripheral side of the connecting member 110.

(2) Friction connecting portion The friction connecting portion 120 is for braking the rotation of the drive shaft 33 by friction engagement, and is provided on the outer peripheral side of the connecting member 110. The friction coupling portion 120 includes a first friction disk 121, a plurality of second friction disks 123, and a back plate 125.

  The first friction disk 121 is engaged with the housing 2, and more specifically, with a plurality of fixing bolts 21 penetrating the housing 2 in the axial direction so as to be relatively non-rotatable and relatively movable in the axial direction. It is a member. Specifically, a plurality of first external teeth 122 arranged in the circumferential direction and projecting outward in the radial direction are formed on the outer peripheral side of the first friction disk 121. A plurality of first friction disks 121 are arranged so that the first external teeth 122 engage with the fixing bolts 21.

  The second friction disk 123 is an annular member that is disposed so as to sandwich the first friction disk 121 and engages with the connecting member 110 so as not to be relatively rotatable and relatively movable in the axial direction. Specifically, on the inner peripheral side of the second friction disk 123, a plurality of second internal teeth 124 that are arranged in the circumferential direction and project inward in the radial direction are formed. A plurality of second friction disks 123 are arranged so that the second inner teeth 124 engage with the second outer teeth 111 of the connecting member 110.

  The back plate 125 is an annular member for receiving an axial biasing force from the diaphragm spring 132. The back plate 125 is sandwiched between the first ring gear 45 and the cylindrical portion 35 c extending in the axial direction from the outer peripheral side of the motor cover 35. Further, the back plate 125 is engaged with the fixing bolt 21 so as not to be relatively rotatable.

(3) Parking brake operating mechanism The parking brake operating mechanism 130 is for braking the rotation of the drive shaft 33 to place the vehicle in a parking state. Specifically, the parking brake operating mechanism 130 is for applying an axial urging force to the friction coupling portion 120 to frictionally engage the friction coupling portion 120. Arranged on the side. The parking brake operating mechanism 130 mainly includes a pressure plate 131 (pressing member), a diaphragm spring 132 (biasing member), two rings 133, a plurality of stop pins 134 (fixing members), and a parking brake piston 135. (Piston) and a parking hydraulic chamber 136. FIG. 3 shows a state where the urging force of the diaphragm spring 132 is released, that is, a state where the parking brake is not operated.

  The pressure plate 131 is an annular member disposed in the vicinity of the friction coupling portion 120. The pressure plate 131 is disposed so as not to rotate relative to the housing 2 and to be relatively movable in the axial direction. Specifically, on the outer peripheral side of the pressure plate 131, a plurality of third external teeth 131b arranged in the circumferential direction and protruding outward in the radial direction are formed. Similar to the first friction disk 121, the pressure plate 131 is arranged so that the third external teeth 131 b engage with the fixing bolt 21. The pressure plate 131 has a plurality of second protrusions 131a for receiving a biasing force from the diaphragm spring 132.

  The diaphragm spring 132 is an annular member disposed on the axial motor 3 side of the pressure plate 131 for biasing the pressure plate 131 in the axial direction with respect to the friction coupling portion 120. The diaphragm spring 132 is supported so as to be elastically deformable in the axial direction with respect to the motor cover 35 and not relatively rotatable. The diaphragm spring 132 is set in a state where the pressure plate 131 is urged toward the axial drive wheel 8 side (the right side in FIG. 3). The diaphragm spring 132 includes an annular portion 132a and a plurality of lever portions 132b.

  The annular portion 132 a is for urging the pressure plate 131 and is formed on the outer peripheral side of the diaphragm spring 132. The lever part 132b is a part protruding radially inward from the annular part 132a. A stop pin 134 is disposed between the lever portions 132b on the inner peripheral side of the annular portion 132a. A head 134 a having an outer diameter larger than that of the main body 134 b is formed at the tip of the stop pin 134, and a diaphragm spring 132 is sandwiched between the head 134 a and the motor cover 35 together with the ring 133. Yes. With these configurations, the diaphragm spring 132 can be elastically deformed in the axial direction with the contact portion with the ring 133 as a fulcrum, and cannot rotate relative to the motor cover 35.

  The parking brake piston 135 is an annular member for releasing the urging force of the diaphragm spring 132 by hydraulic pressure, and is fitted on the outer peripheral side of the cover member 36. A first recess 35 b is formed in the motor cover 35 on the outer peripheral side of the cover member 36. An annular parking hydraulic chamber 136 is formed between the parking brake piston 135 and the first recess 35b in the axial direction, and is sealed by three second seal members 137 provided on the motor cover 35 and the cover member 36. ing. An oil passage 102 is connected to the parking hydraulic chamber 136, and for example, hydraulic pressure can be supplied from a hydraulic pump (not shown) driven by the electric motor 3 via the hydraulic plug 101 and the oil passage 102. A snap ring 138 for restricting the stroke of the parking brake piston 135 is provided on the outer peripheral side of the cover member 36. The parking brake piston 135 can bias the inner peripheral end of the lever portion 132b of the diaphragm spring 132.

  As described above, since the rotation of the drive shaft 33 can be braked by the first reduction gear 40 provided on the upstream side of the reduction gear 4, when a parking brake device is provided around the drive wheel 8 as in the prior art. In comparison, the braking force required to maintain the parking state can be reduced. As a result, the friction surface can be reduced. Further, by using the diaphragm spring 132, a larger urging force can be applied to the friction coupling portion 120 than in the case where a coil spring is used as in the conventional case, and the friction surface can be further reduced. . Furthermore, the axial dimension of the diaphragm spring 132 is smaller than that of the coil spring. As described above, in the drive device 1 equipped with the parking brake device 100, the space around the speed reduction device 4 can be effectively used, the axial dimension of the parking brake device 100 can be shortened, and the axial direction of the entire drive device 1 can be reduced. Dimensions can be shortened.

4). Operation The operation of the drive device 1, particularly the operation of the parking brake device 100, will be described with reference to FIG.

  In the parking state, the diaphragm spring 132 urges the pressure plate 131 in the axial direction, and the friction coupling portion 120 is held between the pressure plate 131 and the back plate 125. As a result, the first friction disk 121 and the second friction disk 123 are frictionally engaged, and the relative rotation between the housing 2 and the connecting member 110 is braked by the frictional force generated on each friction surface. As a result, the rotation of the drive wheels 8 is also braked, and the vehicle is parked. At this time, the necessary braking force for braking the rotation of the drive wheel 8 is reduced by the amount decelerated by the second reduction gear 44. Therefore, the friction surface can be reduced and the axial dimension of the parking brake device 100 can be shortened. Thereby, the axial direction dimension of the whole drive device 1 can be shortened.

  When canceling the parking state, hydraulic pressure is supplied to the parking hydraulic chamber 136, and the parking brake piston 135 urges the inner peripheral end of the lever portion 132b of the diaphragm spring 132 toward the axial drive wheel 8. As a result, the diaphragm spring 132 is elastically deformed in the axial direction with the stop pin 134 as a fulcrum, and the annular portion 132a moves to the axial direction motor 3 side. Thereby, the urging force to the pressure plate 131 is released, and the frictional engagement between the first friction disk 121 and the second friction disk 123 is released. Then, as shown in FIG. 3, the parking state is released, and the vehicle can travel.

  When the parking state is set again from this state, the supply of hydraulic pressure to the parking hydraulic chamber 136 is stopped. As a result, the biasing force of the parking brake piston 135 to the inner peripheral end of the lever portion 132b is released, and the diaphragm spring 132 returns to its original state. As a result, the vehicle is parked.

5. Effects The effects of the dual clutch device according to the present invention are summarized below.

-Reduction of axial dimension In this drive device 1, the rotation of the drive shaft 33 can be braked by the first reduction device 40 provided on the upstream side of the reduction device 4. As compared with the case where the parking brake device is provided in the vehicle, the braking force required to maintain the parking state can be reduced. As a result, the friction surface of the parking brake device 100 can be reduced.

  Further, by using the diaphragm spring 132 in the parking brake device 100, it is possible to apply a larger urging force to the friction coupling portion 120 as compared with the case where the coil spring is used as in the related art. Specifically, the annular portion 132a on the outer peripheral side of the diaphragm spring 132 urges the pressure plate 131, and the inner peripheral side of the annular portion 132a is fixed by the stop pin 134, so that the pressure plate 131 is urged ( By adjusting the action point) and the position (fulcrum) of the stop pin 134, a larger biasing force than that of the conventional coil spring can be applied. As a result, the friction surface in the parking brake device 100 can be further reduced.

  Further, the diaphragm spring 132 is smaller in the axial dimension than the coil spring as a member for biasing the friction coupling portion 120.

  As described above, in this drive device 1, the space around the speed reduction device 4 can be effectively used, the axial dimension of the parking brake device 100 can be shortened, and the axial dimension of the entire drive device 1 can be shortened. .

6). Other Embodiments The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the scope of the present invention.

(1) Electric motor In the above-described embodiment, the power generator is described as the electric motor 3 (SR motor), but is not limited thereto, and may be another type of motor, engine, or the like.

(2) Diaphragm spring In the above-described embodiment, the diaphragm spring 132 is configured by a single plate, but is not limited thereto, and may be configured by a plurality of plates.

1 is a cross-sectional view of a drive device 1 as a first embodiment of the present invention. Sectional drawing around a reduction gear. Sectional drawing of the parking brake device 100 periphery as 1st Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drive device 2 Housing 3 Electric motor (power generator)
4 Reduction gear 5 Differential gear 6 Axle 8 Drive wheel 35 Motor cover (support member)
36 Cover member (support member)
40 First reduction device 44 Second reduction device 100 Parking brake device 110 Connecting member 120 Friction connecting portion 130 Parking brake operating mechanism 131 Pressure plate (pressing member)
132 Diaphragm spring (biasing member)
134 Stop pin (fixing member)
135 Parking brake piston (piston)

Claims (9)

A drive device for running a vehicle,
A housing;
A power generator,
A drive shaft extending from the power generator;
A speed reduction device arranged on the same axis as the drive shaft for reducing the rotation of the drive shaft;
A parking brake device for braking the rotation of the drive shaft,
The speed reduction device includes a connecting member that rotates by torque transmitted from the drive shaft,
The parking brake device includes an annular friction coupling portion for braking relative rotation of the coupling member with respect to the housing by friction engagement, and an axial biasing force applied to the friction coupling portion to provide the friction coupling portion. And a parking brake operating mechanism for frictionally engaging the vehicle. The parking brake operating mechanism is
A pressing member disposed in proximity to the frictional coupling part;
An annular urging member for urging the pressing member in the axial direction with respect to the friction coupling portion;
An annular piston for releasing the urging force of the urging member by hydraulic pressure,
The vehicle drive device according to claim 1. The reduction device includes a first reduction device for reducing the rotation of the drive shaft, and a second reduction device for further reducing the rotation output from the first reduction device,
The first reduction gear unit connects the plurality of first planetary gears meshed with the outer peripheral side of the drive shaft, the annular first ring gear provided on the outer circumferential side to mesh with the first planetary gear, and the plurality of first planetary gears. An annular connecting member provided to
The vehicle drive device according to claim 1 or 2. An annular support member extending between the power generator and the speed reducer is fixed to the housing,
The urging member has an annular portion that urges the pressing member, and a plurality of lever portions that protrude radially inward from the annular portion,
The parking brake operating mechanism is disposed between the lever portions on the inner peripheral side of the annular portion, and the biasing member can be elastically deformed in the axial direction with respect to the support member and cannot be relatively rotated. It further has a plurality of fixing members for connecting,
The vehicle drive device according to claim 2 or 3. The piston can bias the inner peripheral end of the lever portion in the axial direction.
The vehicle drive device according to any one of claims 2 to 4. The biasing member is composed of a plurality of plate members.
The vehicle drive device according to any one of claims 2 to 5. The friction connecting portion is disposed on the outer peripheral side of the connecting member.
The vehicle drive device according to claim 1. The friction coupling portion is
A plurality of annular first friction disks engaged with the housing in a relatively non-rotatable and axially movable manner;
A plurality of annular second friction disks engaged with the outer peripheral portion of the connecting member so as not to be relatively rotatable and to be relatively movable in the axial direction;
The vehicle drive device according to claim 1. The support member includes a thrust bearing that supports the connecting member so as to be relatively rotatable and receives an axial load from the connecting member.
The vehicle drive device according to any one of claims 4 to 8.

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