JP2006183840A - Driving force distributing device to right and left of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving force distributing device to the right and left shortened in longitudinal length and free from the occurrence of an oil leakage. <P>SOLUTION: The driving force distributing device to the right and left is provided with a differential gear for distributing driving force transmitted through a drive shaft, to right and left axles and absorbing the rotating speed difference of the right and left axles; a hydraulic motor for imparting relative rotating force to the right and left axles; a hydraulic pump for discharging an operating fluid for driving the hydraulic motor by the driving force transmitted through the drive shaft; an operation control valve for regulating the pressure of the operating fluid discharged by the hydraulic pump; and a directional control valve for performing supply control of the operating fluid regulated in pressure by a differential control valve, to the hydraulic motor to generate rotating speed difference between the right and left axles. A partition plate member with a built-in hydraulic control circuit for performing the pressure regulation control of the operating fluid discharged by the hydraulic pump, in cooperation with the operation control valve is provided between the hydraulic motor and the hydraulic pump. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a left / right driving force distribution device for a vehicle.

For example, in Patent Document 1, a turning force (yaw moment) is generated by a difference in driving force between left and right driving wheels by actively changing the distribution of driving force to the left and right driving wheels according to the turning state of the vehicle. A left and right driving force distribution device has been proposed.
As shown in FIG. 5, the left / right driving force distribution device 1 for a vehicle distributes the driving force transmitted via the drive shaft 2 equally to the left and right axles 3, 4 and rotates the left and right axles 3, 4. A differential 5 that absorbs the number difference, a hydraulic motor 6 that applies a relative rotational force between the left and right axles 3 and 4, and a hydraulic pump 7 that discharges hydraulic fluid for driving the hydraulic motor 6. The pressure control valve 8 for regulating the pressure of the hydraulic oil discharged from the hydraulic pump 7 and the oil passage for supplying and discharging the hydraulic oil regulated by the pressure control valve 8 to the hydraulic pump 7 are switched in the forward and reverse directions. A direction switching valve 9 is provided.

  When the direction switching valve 9 is appropriately switched by a control unit (not shown), the rotational force of the hydraulic motor 6 directly acts between the left and right axles 3 and 4 to produce a rotational difference, whereby the left axle 3 is While the speed is increased, the right axle 4 is decelerated, or the right axle 4 is accelerated while the left wheel 3 is decelerated, and the driving force transmitted through the drive shaft 2 increases or decreases. It is distributed to the left and right axles 3 and 4 according to the speed ratio.

  However, in the above-described conventional left and right driving force distribution device, the hydraulic motor 6 is housed in the differential carrier 10 together with the differential device 5, but the hydraulic pump 7, the pressure control valve 8 and the direction switching valve 9 are provided. The hydraulic unit that is provided is disposed in a state of projecting toward the rear of the vehicle body at a position opposite to the drive shaft 2 of the differential carrier 10. For this reason, when the left / right driving force distribution device 1 is used as a rear differential, for example, even if a slight impact force such that the rear bumper at the rear of the vehicle body is recessed is received, the direction switching valve 9 located at the rear end of the hydraulic unit Could be damaged. If the direction switching valve 9 is damaged, there is a possibility that the driving force distribution control in the hydraulic unit may be hindered.

  Even if the hydraulic unit is sufficiently fastened and fixed to the differential carrier 10, the hydraulic pump 7 has a discharge pressure of, for example, about 300 kgf, and thus cannot withstand the discharge pressure from the joint surface between the hydraulic unit and the differential carrier 10. Oil leakage may occur.

JP 2003-130175 A

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and can be shortened in the front-rear length, and the right and left driving force that does not cause oil leakage. An object is to provide a distribution device.

In order to achieve the above object, the invention according to claim 1 is a differential device that distributes the driving force transmitted through the drive shaft to the left and right axles and absorbs the rotational speed difference between the left and right axles; A hydraulic motor that applies a relative rotational force to the left and right axles, a hydraulic pump that discharges hydraulic oil for driving the hydraulic motor by a driving force transmitted through the drive shaft, and a discharge by the hydraulic pump An operation control valve that regulates the pressure of the hydraulic oil, and direction switching that causes the hydraulic motor to supply and discharge the hydraulic oil regulated by the operation control valve to cause a difference in rotational speed between the left and right axles. In the left and right driving force distribution device comprising a valve,
A partition plate member is provided between the hydraulic motor and the hydraulic pump. The partition plate member has a built-in hydraulic control circuit that controls the hydraulic fluid discharged from the hydraulic pump in cooperation with the operation control valve. .

  In order to achieve the above object, according to a second aspect of the present invention, in addition to the structure of the first aspect, the partition plate member is disposed between the hydraulic motor and the hydraulic pump. In this case, it is formed integrally with the housing of the hydraulic motor.

  In order to achieve the above-mentioned object, the invention according to claim 3 is configured in such a manner that, in addition to the configuration of the invention according to claim 1, the partition plate member is disposed between the hydraulic motor and the hydraulic pump. In this case, a part of the hydraulic chamber of the hydraulic pump is formed.

  In order to achieve the above object, according to a fourth aspect of the invention, in addition to the configuration of the first aspect of the invention, the direction switching valve has a longitudinal direction substantially the same as the axial direction of the drive shaft. It is arranged in the left and right driving force distribution device in a state of facing.

  According to the first aspect of the present invention, the partition plate is provided between the hydraulic motor and the hydraulic pump, and includes a hydraulic control circuit that controls the pressure of the hydraulic oil discharged from the hydraulic pump in cooperation with the operation control valve. A member is provided. As a result, the hydraulic unit can be directly fixed to the housing of the left and right driving force distribution device by a plurality of fixing bolts having a large shaft diameter similar to those used when fixing the housings to each other. Tightening that can sufficiently withstand the discharged hydraulic pressure is possible, eliminating the possibility of oil leakage. Further, the hydraulic pump is provided in the left and right driving force distribution device main body, and the hydraulic control circuit is built in the partition plate member, thereby shortening the front and rear length of the entire left and right driving force distribution device, thereby It is possible to suppress overhanging and prevent malfunction even in a slight collision.

  According to the second aspect of the present invention, the partition plate member is integrally formed with the housing of the hydraulic pump when it is disposed between the hydraulic motor and the hydraulic pump. Thereby, in addition to the effect of the invention of the first aspect, the full width of the left and right driving force distribution device can be further reduced and the weight can be reduced. Furthermore, the number of parts and the manufacturing cost can be reduced.

  According to the third aspect of the present invention, the partition plate member forms a part of the hydraulic chamber of the hydraulic pump when it is disposed between the hydraulic motor and the hydraulic pump. Thereby, in addition to the effect of the invention of the first aspect, the entire left and right driving force distribution device can be made more compact.

  According to the fourth aspect of the present invention, the direction switching valve is disposed in the left and right driving force distribution device in a state where the longitudinal direction thereof is substantially in the same direction as the axial direction of the drive shaft. Thereby, in addition to the effect of the invention described in claim 1, the longitudinal length of the left and right driving force distribution device can be further shortened.

  The front-rear length is shortened by providing a partition plate member with a built-in hydraulic control circuit for regulating the pressure of the hydraulic oil discharged from the hydraulic pump in cooperation with the operation control valve between the hydraulic pump and the hydraulic motor. Moreover, a left / right driving force distribution device that does not cause oil leakage has been realized.

  An embodiment of the present invention will be described below with reference to the drawings. 1 is an exploded configuration diagram of a left and right driving force distribution device for a vehicle to which the present invention is applied, FIG. 2 is a plan sectional view of the same example, FIG. 3 is a side view of a partition plate member of the same example, FIG. FIG. 4 is a rear view of FIG. 3.

  The present invention is applied to a left and right driving force distribution device that generates a turning force based on a difference in driving force between left and right driving wheels by actively changing the distribution of driving force to the left and right driving wheels according to the turning state of the vehicle. Is.

  More specifically, as shown in FIGS. 1 and 2, the left / right driving force distribution device 11 distributes the driving force transmitted through the drive shaft 12 to the left and right axles 13, 14 and the left and right axles 13, 14. The differential device 15 that absorbs the rotational speed difference of 14, the hydraulic motor 16 that applies relative rotational force to the left and right axles 13, 14, and the hydraulic motor 16 by the driving force transmitted through the drive shaft 12. The hydraulic pump 17 that discharges the hydraulic oil for driving, the operation control valve 18 that controls the pressure of the hydraulic oil discharged by the hydraulic pump 17, and the hydraulic oil that is regulated by the operation control valve 18 is supplied to the hydraulic motor 16. A directional switching valve 19 is provided that controls the supply and discharge to produce a rotational speed difference between the left and right axles 13 and 14.

  The differential device 15 is disposed in the differential carrier 20 in an offset state on one side of the vehicle body. A planetary gear type is used for the differential device 15, and the driving force from the engine side transmitted through the drive shaft 12 rotatably supported by the differential carrier 20 is transmitted to the drive pinion 21, the ring gear 22, and the like. Is transmitted to the differential case 23 rotatably supported by the differential carrier 20, and further transmitted to the plurality of planetary gears 25 and the sun gear 26 via the ring gear 24 on the inner peripheral side of the differential case 23. A support member 27 that rotatably supports a plurality of planetary gears 25 is coupled and coupled to the right axle 14 via side covers 28 and 29 of the hydraulic motor 16, and the sun gear 26 is coupled and fixed to the left axle 13. Has been. As a result, the differential device 15 equally distributes the driving force transmitted via the drive shaft 12 to the left and right axles 13 and 14 and absorbs the difference in rotational speed between the left and right axles 13 and 14 by the rotation of the planetary gear 25. Is configured to do.

  The hydraulic motor 16 is disposed in a housing 30 that is integrally assembled on the side of the differential carrier 20 adjacent to the differential device 15 in the axial direction so as to form a part of the differential carrier 20. A radial plunger type hydraulic motor is used as the hydraulic motor 16, and when hydraulic oil discharged from the hydraulic pump 17 is supplied and discharged through the supply and discharge oil passages 31 and 31 formed in the differential carrier 20. A plunger 33 inserted into a plurality of radial cylinders 32 formed inside the motor so as to be able to advance and retreat is engageable with a cam ring 35 via a rotatable roller 34 provided on the tip side thereof. The inner peripheral surface of the cam ring 35 continues from the plunger 33 when the hydraulic oil is alternately supplied to and discharged from the plunger 33 via the supply and discharge oil passages 36 and 36 inside the hydraulic motor 16. It is formed so as to be given a rotational motion. A side cover 28 extending in the axle direction so as to be continuous with the support member 27 is integrally connected to the left side portion of the cam ring 35, and is connected to the right axle 14 at the right side portion of the cam ring 35. The side cover 29 formed in the above is integrally connected. For this reason, the side covers 28 and 29 and the cam ring 35 always rotate integrally with the support member 27.

  The hydraulic pump 17 constitutes a hydraulic unit together with the operation control valve 18 and the direction switching valve 19, and is disposed in the differential carrier 20 on the side different from the position where the drive shaft 12 is disposed. An axial swash plate type piston pump is used for the hydraulic pump 17, and when the shaft 38 meshed with the ring gear 37 on the outer periphery of the differential case 23 is driven, the cylinder block 39 connected to the shaft 38 is moved into the differential carrier 20. A plurality of pistons 41, which are rotated at the rear and inserted into a cylinder 40 as a hydraulic chamber so as to be movable back and forth, slide on a tiltable swash plate 42 and reciprocate at a stroke corresponding to the tilt of the swash plate 42. By repeating the above, hydraulic oil sucked from a reservoir tank (not shown) through the partition plate member 43 is discharged toward a hydraulic control circuit (not shown) built in the partition plate member 43. Yes.

  The partition plate member 43 is disposed between the differential 15 and the hydraulic motor 16 so as to serve also as the housing 30 of the hydraulic motor 16, and is in a state of being joined to the side of the hydraulic pump 17. As shown in FIG. 3, a hydraulic control circuit that forms part of the cylinder 40 of the hydraulic pump 17 and controls the hydraulic oil from the cylinder 40 to a necessary pressure and supplies it to the hydraulic motor 16 side. The built-in hydraulic control circuit 44 and the side cover 28 disposed on the outer peripheral side of the hydraulic motor 16 are rotatably accommodated, and the insertion hole 45 through which the axle 13 (the boss portion of the side cover 28) can be inserted is integrated. And a concave storage portion 46 formed integrally with each other.

  On one side of the hydraulic control circuit 44, as shown in FIG. 4, a semicircular suction oil passage 47 that communicates with the reservoir tank and sucks hydraulic oil into the cylinder 40, and from the cylinder 40. A semicircular discharge oil passage 48 for introducing discharged hydraulic oil into the hydraulic control circuit and a bearing portion 49 that rotatably supports the end portion of the shaft 38 are integrally formed. Furthermore, an operation control valve 18 that is controlled by hydraulic oil generated by the electronic control pump 50 behind the hydraulic pump 17 is disposed on the side of the hydraulic control circuit unit 44. The operation control valve 18 cooperates with the hydraulic control circuit so that the hydraulic oil introduced from the discharge oil passage 48 to the hydraulic control circuit is regulated to the required hydraulic pressure to control torque distribution on the left and right wheels. It is configured. The hydraulic oil regulated by the hydraulic control circuit is switched in one of two forward and reverse directions by a control unit (not shown) in the direction of the directional switching valve 19 above the differential carrier 20. Thereafter, the oil is supplied to the hydraulic motor 16 via the supply / discharge oil passages 31 and 31.

  The partition plate member 43 has a large shaft diameter that is threaded into a nut hole 52 formed in the differential carrier 20 through a plurality of bolt holes 51 formed around the hydraulic control circuit portion 44 and the accommodating portion 46. The plurality of fixing bolts 53 are firmly coupled and fixed in close contact with the differential carrier 20 so that oil leakage due to high discharge pressure does not occur.

  As the direction switching valve 19, for example, a two-position, four-port electromagnetic direction switching valve is used. When the direction switching valve 19 is switched to a neutral state by a control unit (not shown), the supply / discharge oil passages 31, 31 and the reservoir tank of the differential carrier 20 are used. And the side covers 28 and 29 of the hydraulic motor 16 and the cam ring 35 are brought into a freely rotating state. In this state, the driving force from the drive shaft 12 that has passed through the differential device 15 is equally transmitted to the left and right axles 13 and 14.

  Further, when the direction switching valve 19 is switched to one side by the control unit, the one supply / discharge oil passage 31 of the differential carrier 20 and the hydraulic pump 17 communicate with each other, and the other supply / discharge oil passage 31 and the reservoir tank are connected. Communicate. In this state, high-pressure hydraulic oil is supplied from one supply / discharge oil passage 31 to one supply / discharge oil passage 36 in the hydraulic motor 16 and from the other supply / discharge oil passage 36 to the other supply / discharge oil. Returning to the oil passage 31, the plunger 33 of the hydraulic motor 16 causes the cam ring 35 to rotate in one direction. Then, the differential case 23 and the sun gear 26 rotate in the same direction through the support member 27 coupled and fixed to the boss portion of the side cover 28 to increase the speed of the left axle 13 while decelerating the right axle 14. Thus, the driving force from the drive shaft 12 is distributed to the left and right axles 13 and 14 in accordance with the rate of acceleration / deceleration.

  Further, when the direction switching valve 19 is switched to the other side by the control unit, the other supply / discharge oil passage 31 of the differential carrier 20 and the hydraulic pump 17 communicate with each other, and the one supply / discharge oil passage 31 and the reservoir tank are connected to each other. Communicate. In this state, high-pressure hydraulic oil is supplied from the other supply / discharge oil passage 31 to the other supply / discharge oil passage 36 in the hydraulic motor 16 and from one supply / discharge oil passage 36 to one supply / discharge oil. Returning to the oil passage 31, the plunger 33 of the hydraulic motor 16 rotates the cam ring 35 in the other direction. Then, unlike the previous case, the differential case 23 and the sun gear 26 rotate relative to each other via the support member 27 coupled and fixed to the boss portion of the side cover 28 to accelerate the right axle 14 while the left axle 13 is moved. By decelerating, the driving force from the drive shaft 12 is distributed to the left and right axles 13 and 14 in accordance with the rate of acceleration / deceleration.

  As described above, according to the present invention, the hydraulic control circuit that controls the pressure of the hydraulic oil discharged from the hydraulic pump 17 in cooperation with the operation control valve 18 is provided between the hydraulic motor 16 and the hydraulic pump 17. A built-in partition member 43 is provided. As a result, the hydraulic unit is directly fixed to the differential carrier 20 of the left and right driving force distribution device 11 by a plurality of fixing bolts 53 having a large shaft diameter in the same manner as used when fixing the housings to each other. Therefore, it is possible to perform tightening that can sufficiently withstand the hydraulic pressure discharged from the hydraulic pump 17, and there is no possibility of oil leakage. Further, the hydraulic pump 17 is provided in the left and right driving force distribution device 11 body, and the hydraulic control circuit is also built in the partition plate member 43, thereby shortening the longitudinal length of the entire left and right driving force distribution device 11. This suppresses overhanging in the longitudinal direction of the vehicle body and prevents malfunction even in a slight collision.

  Furthermore, according to the present invention, the partition plate member 43 is integrally formed with the housing of the hydraulic pump 17 when it is disposed between the hydraulic motor 16 and the hydraulic pump 17. Thereby, the full width of the left and right driving force distribution device 11 can be further reduced and the weight can be reduced. Furthermore, the number of parts and the manufacturing cost can be reduced.

Furthermore, according to the present invention, the partition plate member 43 forms a part of the cylinder 32 of the hydraulic pump 17 when it is disposed between the hydraulic motor 16 and the hydraulic pump 17. Thereby, the left-right driving force distribution device 11 as a whole can be made more compact.
Furthermore, according to the present invention, the direction switching valve 19 is disposed in the left and right driving force distribution device 11 with its longitudinal direction facing substantially the same direction as the axial direction of the drive shaft 12. Thereby, the front-rear length of the left and right driving force distribution device 11 can be further shortened.

  As a result, it is possible to provide a left-right driving force distribution device that can shorten the front-rear length and that does not cause oil leakage.

1 is an exploded configuration diagram of a left and right driving force distribution device for a vehicle to which the present invention is applied. It is a plane sectional view in the example. It is one side view of the partition plate member in the example. FIG. 4 is a rear view of FIG. 3. It is a cross-sectional view of a conventional vehicle left and right driving force distribution device.

Explanation of symbols

11 Left and right driving force distribution device 12 Drive shaft 13 Axle 14 Axle 15 Differential device 16 Hydraulic motor 17 Hydraulic pump 18 Operation control valve 19 Directional switching valve 30 Housing 43 Partition plate member 44 Hydraulic control circuit section

Claims (4)

A differential that distributes the driving force transmitted through the drive shaft to the left and right axles and absorbs the difference in rotational speed between the left and right axles;
A hydraulic motor for applying a relative rotational force to the left and right axles;
A hydraulic pump that discharges hydraulic oil for driving the hydraulic motor by a driving force transmitted through the drive shaft;
An operation control valve for controlling the pressure of the hydraulic oil discharged from the hydraulic pump;
In the left and right driving force distribution device comprising a direction switching valve that controls the supply and discharge of the hydraulic oil regulated by the operation control valve to the hydraulic motor to generate a rotational speed difference between the left and right axles,
A partition plate member is provided between the hydraulic motor and the hydraulic pump. The partition plate member has a built-in hydraulic control circuit that controls the hydraulic fluid discharged from the hydraulic pump in cooperation with the operation control valve. Vehicle left / right driving force distribution device.   The left-right drive for a vehicle according to claim 1, wherein the partition plate member is integrally formed with a housing of the hydraulic motor when the partition plate member is disposed between the hydraulic motor and the hydraulic pump. Power distribution device.   2. The vehicle according to claim 1, wherein the partition plate member forms a part of a hydraulic chamber of the hydraulic pump when the partition plate member is disposed between the hydraulic motor and the hydraulic pump. Left and right driving force distribution device.   2. The vehicle according to claim 1, wherein the direction switching valve is disposed in the left and right driving force distribution device in a state in which a longitudinal direction thereof is substantially in the same direction as an axial center direction of the drive shaft. Left and right driving force distribution device.

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