JP2005029117A - Drive device for vehicles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a driving mechanism having a high gear reduction ratio and a brake to be assembled in a compact housing of a drive device for vehicles. <P>SOLUTION: This drive device 1 for vehicles comprises a wheel hub 3 supporting a vehicle wheel 2, a spur gear reducer 4 for reducing a rotational output of a motor and transmitting the output to the wheel hub 3, and a wet disk brake 7 for braking a rotation of the wheel hub 3. The spur gear reducer 4 comprises a pinion spur gear 41 connected to a motor shaft 10 and a large spur gear 42 engaged with the pinion spur gear 41. The wet disk brake 7 comprises a brake disk 71 and a pressure plate 72 and the wet disk brake 7 is installed inside the large spur gear 42. The pressure plate 72 reduces a rotation of the large spur gear 42 and brakes a rotation of the wheel hub 3 by depressing the brake disk 71 against a stopper 48 arranged at a flange part 46 of the large spur gear 42. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle drive device that rotationally drives a wheel hub that supports a wheel of a vehicle using a rotational output of a motor.

  Conventionally, a vehicle drive device that rotationally drives a wheel hub by reducing the rotational output of a motor by a spur gear reducer and a planetary gear reducer, and transmitting the reduced rotational output to a wheel hub via a drive shaft. There is. In this type of vehicle drive device, a spur gear reducer, a planetary gear reducer, and a drive shaft are generally housed in a housing, and a wheel hub is connected to the drive shaft from the inside of the housing. .

  The spur gear reducer has a pinion spur gear connected to the shaft of the motor and a large spur gear meshed with the pinion spur gear. The planetary gear reducer includes a sun gear that rotates coaxially with the rotation shaft of the large spur gear according to the rotation of the large spur gear of the spur gear reducer, a ring gear provided in a housing around the sun gear, a sun gear, It has a planetary gear that meshes with the ring gear and revolves around the sun gear by the rotation of the sun gear, and a planet carrier that rotates coaxially with the rotation axis of the sun gear by the revolution of the planetary gear.

  In such a vehicle drive device, a wet disc brake is used as a brake for braking the rotation of the wheel hub, and the wet disc brake is disposed between the large spur gear of the spur gear reducer and the ring gear of the planetary gear reducer. The thing is known (for example, refer patent document 1 and patent document 2).

  In the device described in Patent Document 1, the wet disc brake includes an inner disc, an outer disc, and a pressure plate, and these are arranged between the large spur gear and the planetary gear reducer. The inner disk and the outer disk are alternately stacked in the direction of the rotation axis of the large spur gear, and the inner disk is connected to the large spur gear and rotates together with the large spur gear, while the outer disk is rotated by a ring gear so as not to rotate. It is connected to the housing via. The pressure plate is connected to the large spur gear, rotates together with the large spur gear, and is pressed by the pre-piston, thereby pressing the inner disk and the outer disk against each other.

  In the device described in Patent Document 2, the wet disc brake includes an inner disc and an outer disc, and these are arranged between the large spur gear and the planetary gear reducer. Similar to the device described in Patent Document 1, the inner disk and the outer disk are alternately stacked in the direction of the rotation axis of the large spur gear, the inner disk is connected to the large spur gear, and the outer disk has a ring gear. It is connected to the housing via. The large spur gear is pressed against the inner disk and the outer disk by being pressed by the pre-piston.

The devices described in both Patent Document 1 and Patent Document 2 are separate members from the large spur gear of the spur gear reducer and the sun gear of the planetary gear reducer, and the large spur gear and the sun gear are connected by bolts. It has a fixed configuration.
DE4321699C1 USP 5,147,255

  However, in the conventional vehicle drive device described above, a wet disk brake is disposed between the large spur gear of the spur gear reducer and the ring gear of the planetary gear reducer. That is, an area for disposing a wet disc brake is provided between the large spur gear and the planetary gear reducer, and the wet disc brake is disposed in the area. For this reason, a large housing is required, and the vehicle drive device has been enlarged. Further, since the pressure plate rotates, wear occurs between the pressure plate and the pre-piston that presses the pressure plate.

  The present invention has been made to solve the above-described problems, and a drive mechanism and a brake having a large reduction ratio can be incorporated in a compact housing, and wear occurs between the pressure plate and the pre-piston. An object of the present invention is to provide a non-vehicle drive device.

  In order to achieve the above object, a first aspect of the present invention provides a vehicle drive device that includes a wheel hub that supports a wheel of a vehicle, and that rotates the wheel hub using the rotation output of the prime mover. A spur gear reducer that transmits to the wheel hub, and a brake that brakes the rotation of the wheel hub. The spur gear reducer is meshed with the pinion spur gear to which the output of the prime mover is input, and the pinion spur gear. The brake has a brake disc disposed adjacent to the flange portion of the large spur gear in the rotational axis direction of the large spur gear, and a pressure plate that presses the brake disc against the flange portion. Is pressed against the flange portion to decelerate the rotation of the large spur gear, thereby braking the rotation of the wheel hub.

  In this configuration, the pressure plate and the brake disc can be arranged inside the large spur gear, and a separate area for arranging the brake disc and the pressure plate can be eliminated. As a result, a drive mechanism having a spur gear speed reducer with a large reduction ratio and a brake for braking the rotation of the wheel hub can be incorporated in a compact housing. In addition, the pressure plate can be fixed to the housing, so that the pressure plate does not rub against the pre-piston (not rotating) that presses the pressure plate.

  According to a second aspect of the present invention, in the vehicle drive device according to the first aspect, the brake disk and the pressure plate are disposed inside the large spur gear, and the brake disk rotates from the flange portion of the large spur gear. It has a plurality of inner brake discs and outer brake discs arranged alternately in the axial direction, and the inner brake disc is located inside the large spur gear and is fixed to the housing cover of the spur gear reducer. The outer brake disc is attached to the inner peripheral surface of the large spur gear.

  In this configuration, since the space inside the large spur gear is used as an area for arranging the brake disc and the pressure plate, it is not necessary to separately provide an area for arranging the brake disc and the pressure plate. As a result, a drive mechanism having a spur gear speed reducer with a large reduction ratio and a brake for braking the rotation of the wheel hub can be incorporated in a compact housing.

  According to a third aspect of the present invention, in the vehicle drive device according to the second aspect, the planetary gear speed reducer further includes a planetary gear speed reducer that reduces the rotational output of the spur gear speed reducer and transmits it to the wheel hub. A sun gear that rotates coaxially with the rotation axis of the large spur gear according to the rotation of the gear, a planetary gear that meshes with the sun gear and revolves around the sun gear by the rotation of the sun gear, and a planetary gear that supports the planetary gear It has a planetary carrier that rotates coaxially with the rotation axis of the sun gear by the revolution of the gear, the rotation output of the planet carrier is transmitted to the wheel hub, and the flange portion of the large spur gear is integral with the sun gear. Is.

  In this configuration, since the flange portion of the large spur gear is integral with the sun gear, the operation of connecting and fixing the large spur gear and the sun gear is unnecessary, and the assembling operation is simplified. In addition, the strength of the large spur gear and the sun gear is increased.

  According to a fourth aspect of the present invention, in the vehicle drive device according to the second aspect, a member for restricting the rotation of the pressure plate is inserted into a hole formed in the pressure plate.

  In this configuration, since the rotation of the pressure plate is restrained by inserting the member into the hole of the pressure plate, the structure for restraining the rotation of the pressure plate is simple, and the assembling work is simplified. Further, since the pressure plate does not rotate, the pressure plate does not rub against a pre-piston (not rotating) that presses the pressure plate.

  According to a fifth aspect of the present invention, in the vehicle drive device according to any one of the second to fourth aspects, the flange portion of the large spur gear is composed of a separate member from the gear portion of the large spur gear, and the gear portion and the flange The parts are connected by bolts.

  In this configuration, since the flange portion and the gear portion of the large spur gear are constituted by different members, the flange portion and the gear portion are manufactured by separate forging processes, and the structure of each forging die becomes simple. .

  According to the first aspect of the present invention, since the brake disc is pressed against the flange portion of the large spur gear by the pressure plate, the brake can be arranged in the housing without providing an additional area for arranging the brake. As a result, the drive mechanism for a vehicle having a large reduction ratio having a spur gear reducer and the brake can be incorporated into a compact housing, and the vehicle drive device can be miniaturized. Further, it becomes possible to fix the pressure plate to the housing, so that the pressure plate does not rub against the pre-piston, and no wear occurs between the pressure plate and the pre-piston.

  According to the second aspect of the present invention, the brake disk and the pressure plate are arranged inside the large spur gear, so that the drive mechanism having a large gear ratio and the brake are incorporated in a compact housing. Thus, the vehicle drive device can be reduced in size.

  According to the invention of claim 3, since the flange portion of the large spur gear is integrated with the sun gear, the assembling work is simplified, the manufacturing cost can be reduced, the strength of the large spur gear and the sun gear is increased, and the running performance is improved. To do.

  According to the fourth aspect of the present invention, since the member for restraining the rotation of the pressure plate is inserted into the hole formed in the pressure plate, the assembling work is simplified and the manufacturing cost can be reduced. Further, since the pressure plate does not rotate, the pressure plate does not rub against the pre-piston, and wear does not occur between the pressure plate and the pre-piston.

  According to the invention of claim 5, since the flange portion of the large spur gear is constituted by a member separate from the gear portion of the large spur gear, the large spur gear can be produced by a simple forging die, and the productivity is improved.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. First, a first embodiment of the present invention will be described. 1 and 2, a vehicle drive device 1 rotates a wheel hub 3 that supports a vehicle wheel 2 using a rotation output of a motor (only a motor shaft 10 is illustrated). The vehicle drive device 1 reduces the rotational output of the motor by the spur gear reducer 4 and the planetary gear reducer 5 and transmits the reduced rotational output to the wheel hub 3 via the drive shaft 6. The hub 3 is driven to rotate, and the rotation of the wheel hub 3 is braked by the wet disc brake 7. The spur gear reducer 4, the planetary gear reducer 5, the drive shaft 6, and the wet disc brake 7 are housed in the housing 8, and the wheel hub 3 is connected to the drive shaft 6 from the outside of the housing 8. . The housing 8 is covered with a housing cover 9.

  The spur gear reducer 4 decelerates the rotational output of the motor, and has a pinion spur gear 41 and a large spur gear 42. The pinion spur gear 41 transmits the rotational output of the motor to the large spur gear 42 and is connected to the motor shaft 10. The large spur gear 42 is meshed with the pinion spur gear 41 and rotates according to the rotation of the pinion spur gear 41. The rotational output of the large spur gear 42 is obtained by reducing the rotational output of the pinion spur gear 41 in accordance with the gear ratio between the pinion spur gear 41 and the large spur gear 42. In this large spur gear 42, a shaft portion 45 and a flange portion 46 are configured as separate members from the gear portion 47. Further, the flange portion 46 is provided with a stopper 48 against which a brake disk 71 described later is pressed. The stopper 48 is constrained by the gear portion 47 so as to be movable in the rotational axis direction of the large spur gear 42, and rotates together with the flange portion 46. The gear portion 47 and the flange portion 46 are connected and fixed by bolts 49.

  The spur gear reducer 4 reduces the rotational output of the pinion spur gear 41 according to the gear ratio to the rotational output of the large spur gear 42, thereby reducing the rotational output of the motor shaft 10 transmitted to the pinion spur gear 41. To do.

  The planetary gear speed reducer 5 decelerates the rotational output of the large spur gear 42 (that is, the rotational output of the motor decelerated by the spur gear speed reducer 4). The sun gear 51, the planetary gear 52, the ring gear 53, And a planet carrier 54. The sun gear 51 transmits the rotational output of the large spur gear 42 to the planetary gear 52, and is formed integrally with the shaft portion 45 and the flange portion 46 of the large spur gear 42. It rotates on the same axis as the rotation axis of the gear 42.

  The planetary gear 52 is meshed with the sun gear 51 and the ring gear 53. The ring gear 53 is fixed to the housing 8. The planetary gear 52 revolves around the sun gear 51 in accordance with the rotation of the sun gear 51 by being engaged with the sun gear 51 and the ring gear 53. The revolution output of the planetary gear 52 is obtained by reducing the rotation output of the sun gear 51. The planetary carrier 54 has a structure in which the planetary gear 52 is supported so as to be able to revolve around the sun gear 51, and rotates on the same axis as the rotation axis of the sun gear 51 according to the revolution of the planetary gear 52. The rotation output of the planet carrier 54 is the same as the revolution direction of the planetary gear 52 (thus, the rotation output of the sun gear 51 is decelerated). A carrier bearing 59 is provided between the planet carrier 54 and the housing 8.

  The planetary gear speed reducer 5 revolves the planetary gear 52 using the rotation output of the sun gear 51 and reduces the rotation output of the sun gear 51 by using the revolution output of the planetary gear 52 as the rotation output of the planet carrier 54. Thus, the rotation output of the planetary carrier 54 is set, and thereby the rotation output of the large spur gear 42 transmitted to the sun gear 51 (that is, the rotation output of the motor decelerated by the spur gear reducer 4) is decelerated.

  The drive shaft 6 transmits the rotation output of the planet carrier 54 (that is, the rotation output of the motor decelerated by the planetary gear speed reducer 5) to the wheel hub 3. The drive shaft 6 is formed integrally with the planet carrier 54. The wheel hub 3 and the drive shaft 6 are connected by spline coupling that transmits mutual rotation around the axis, and the fixing bolt 11 is screwed onto the drive shaft 6 from the outside of the wheel hub 3 via the retainer plate 12. As a result, the wheel hub 3 is secured from the drive shaft 6. A bolt cap 13 is attached to the retainer plate 12 so as to cover the head of the fixing bolt 11. A hub bearing 15 is provided between the wheel hub 3 and the housing 8. The wheel hub 3 is rotationally driven by the rotation of the drive shaft 6 to rotate the wheel 2 and the tire 16.

  The wet disc brake 7 brakes the rotation of the wheel hub 3 and is disposed inside the large spur gear 42 of the spur gear reducer 4 and has a plurality of brake discs 71 and a pressure plate 72. ing. The plurality of brake discs 71 are composed of a plurality of inner brake discs 73 and a plurality of outer brake discs 74, and each of the inner brake discs 73 and the outer brake discs 74 is a rotating shaft of the large spur gear 42. They are superposed alternately in the direction and arranged at positions adjacent to the stopper 48. The stopper 48 is constrained so as to be movable in the axial direction on the gear portion 47 of the large spur gear 42 as described above.

  The inner brake disc 73 is supported by a disc support member 75 fixed to the housing cover 9, and the outer brake disc 74 is supported on the inner peripheral surface of the gear portion 47 of the large spur gear 42. The inner brake disc 73 does not rotate, and the outer brake disc 74 rotates with the large spur gear 42. Both the inner brake disc 73 and the outer brake disc 74 are supported so as to be movable in the direction of the rotation axis of the large spur gear 42, and oil is interposed between each inner brake disc 73 and the outer brake disc 74. . The disk support member 75 is fixed to the housing cover 9 by bolts 76, and a spur gear bearing 77 is provided between the disk support member 75 and the shaft portion 45 of the large spur gear 42.

  The pressure plate 72 presses the brake disc 71 against the stopper 48. The pressure plate 72 is moved toward the stopper 48 by being pressed from the outside of the housing cover 9 by the pre-piston 85, and presses the brake disk 71 against the stopper 48. A projecting member 81 formed integrally with the housing cover 9 is inserted into a hole 82 formed in the pressure plate 72, so that the pressure plate 72 is supported so as to be movable in the rotational axis direction of the large spur gear 42. In addition, the rotation of the pressure plate 72 is restricted.

  When the pressure plate 72 is pressed by the pre-piston 85, the wet disk brake 7 presses the brake disk 71 against the stopper 48 by the pressure plate 72, thereby causing friction between each inner brake disk 73 and the outer brake disk 74. Force is generated, and the rotation of the large spur gear 42 is decelerated by this frictional force, and the rotation of the wheel hub 3 is braked.

  According to the vehicle drive device 1 having such a configuration, since the brake disc 71 and the pressure plate 72 are arranged inside the large spur gear 42, an area for arranging the brake disc 71 and the pressure plate 72 is separately provided. There is no need. Thereby, the housing 8 can be made compact and the spur gear reducer 4, the planetary gear reducer 5, and the wet disc brake 7 can be incorporated. Further, since the rotation of the pressure plate 72 is restricted by inserting the protruding member 81 integral with the housing cover 9 into the hole 82 of the pressure plate 72, the structure for restricting the rotation of the pressure plate 72 is simple. In addition, the work of assembling the wet disc brake 7 is simplified. Furthermore, since the pressure plate 72 does not rotate, there is no friction between the pressure plate 72 and the pre-piston 85, and no wear occurs.

  Further, since the flange portion 46 of the large spur gear 42 is integral with the sun gear 51, the assembling work is simplified and the strength of the large spur gear 42 and the sun gear 51 is increased. Further, since the flange portion 46 and the gear portion 47 of the large spur gear 42 are configured as separate members, the flange portion 46 and the gear portion 47 are each manufactured by a forging die having a simple structure. It can be produced using a forging die having a simple structure.

  Next, a second embodiment of the present invention will be described. In FIG. 3, in the vehicular drive apparatus 1 of the present embodiment, the large spur gear 42 is formed integrally with a shaft portion 45, a flange portion 46, and a gear portion 47. The sun gear 51 is formed integrally with the large spur gear 42. That is, in the vehicle drive device 1 of the present embodiment, the shaft portion 45, the flange portion 46, the gear portion 47, and the sun gear 51 of the large spur gear 42 are integrally formed. Other configurations in the present embodiment are the same as those in the first embodiment.

  Also with the vehicle drive device 1 having such a configuration, the spur gear reducer 4, the planetary gear reducer 5, and the wet disc brake 7 can be incorporated by making the housing 8 compact as in the first embodiment. At the same time, the work of assembling the wet disc brake 7 is simplified. Further, according to the vehicle drive device 1 having such a configuration, the shaft portion 45, the flange portion 46, the gear portion 47, and the sun gear 51 of the large spur gear 42 are integrated, so that the assembly work is simplified. The strength of the large spur gear 42 and the sun gear 51 is increased, and the cost is reduced by mass production.

  In addition, this invention is not restricted to the structure of the said embodiment, A various deformation | transformation is possible. For example, in the above embodiment, the stopper 48 may be formed integrally with the flange portion 46. Further, the sun gear 51 is not limited to one integrated with the large spur gear 42 (the flange portion 46 of the large spur gear 42), and may be a separate member. Further, the large spur gear 42 may be a helical gear, a worm gear, or the like.

1 is a cross-sectional view showing a schematic configuration of a vehicle drive device according to a first embodiment of the present invention. The perspective view which fractured | ruptured partially which shows the structure of the drive device for vehicles. Sectional drawing which shows schematic structure of the vehicle drive device which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle drive device 2 Wheel 3 Wheel hub 4 Spur gear reducer 5 Planetary gear reducer 6 Drive shaft 7 Wet disk brake 8 Housing 9 Housing cover 10 Motor shaft 16 Tire 41 Pinion spur gear 42 Large spur gear 46 Flange part of large spur gear 47 Gear portion of large spur gear 48 Stopper 51 Sun gear 52 Planetary gear 54 Planetary carrier 71 Brake disc 72 Pressure plate 73 Inner brake disc 74 Outer brake disc 75 Disc support member 81 Projecting member 82 Hole 85 Pre-piston

Claims (5)

In a vehicle drive device that includes a wheel hub that supports a wheel of a vehicle, and that drives the wheel hub to rotate using a rotational output of a prime mover.
A spur gear reducer that reduces the rotational output of the prime mover and transmits it to the wheel hub;
A brake for braking the rotation of the wheel hub,
The spur gear reducer has a pinion spur gear to which the output of the prime mover is input, and a large spur gear meshed with the pinion spur gear,
The brake includes a brake disk disposed adjacent to a flange portion of the large spur gear in a rotation axis direction of the large spur gear, and a pressure plate that presses the brake disk against the flange portion, and the brake disk is A vehicle drive device characterized by braking the rotation of the wheel hub by depressing the rotation of the large spur gear against the flange portion. The brake disc and the pressure plate are arranged inside the large spur gear,
The brake disc has a plurality of inner brake discs and outer brake discs arranged alternately and alternately in the rotation axis direction of the large spur gear from the flange portion of the large spur gear,
The inner brake disk is supported by a support member that is inside the large spur gear and is fixed to a housing cover of the spur gear reducer,
The vehicle drive device according to claim 1, wherein the outer brake disc is attached to an inner peripheral surface of the large spur gear. A planetary gear reducer that further reduces the rotational output of the spur gear reducer and transmits it to the wheel hub;
The planetary gear reducer includes a sun gear that rotates coaxially with a rotation shaft of the large spur gear according to the rotation of the large spur gear, and a sun gear that meshes with the sun gear and rotates around the sun gear by the rotation of the sun gear. A planetary gear that revolves, and a planetary carrier that supports the planetary gear and rotates on the same axis as the rotation axis of the sun gear by the revolution of the planetary gear, and the rotational output of the planetary carrier is transmitted to the wheel hub. Is,
The vehicle drive device according to claim 2, wherein a flange portion of the large spur gear is integral with the sun gear.   The vehicle drive device according to claim 2, wherein a member that restrains rotation of the pressure plate is inserted into a hole formed in the pressure plate.   The vehicle according to any one of claims 2 to 4, wherein the flange portion of the large spur gear is constituted by a member separate from the gear portion of the large spur gear, and the gear portion and the flange portion are coupled by a bolt. Drive device.

Images