JPH07215081A - Driving force connecting/disconnecting device on four-wheel drive vehicle - Google Patents

Abstract

PURPOSE:To provide a driving force connecting/disconnecting device which automatically connects a side gear shaft and an axle shaft in the four-wheel drive and automatically cuts off the connection in the two-wheel drive. CONSTITUTION:A driving member 11 which is supported in a rotatable manner on a supporting member 12 fixed on a differential carrier, driven member 13 which is supported in a rotatable manner on the supporting member 12 and connected with an axle shaft 25b and positioned concentrically to the outer periphery of a side gear shaft 26b, and the first frictional clutch 14 which is installed between the driving member 11 and the supporting member 12 and is frictionally engaged when the driving member 11 drives are installed. A pressing member 16a which is installed in a shiftable manner in the axial direction on the outer periphery of the driving member 11, the second frictional clutch 17 which is installed between the side gear shaft 26b and the driven member 13 and is frictionally engaged through the pressing by the pressing member 16b and connects the side gear shaft 26b with the driven member 13, and a cam means 18 which is installed between the pressing member 16 and the first frictional clutch 14 and operates in the frictional engagement and shifts the pressing member 16a in the axial direction for the frictional engagement of the second frictional clutch 17 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive force connecting / disconnecting device for a four-wheel drive vehicle.

[0002]

2. Description of the Related Art In a four-wheel drive vehicle capable of switching between a two-wheel drive state and a four-wheel drive state, that is, a part-time type four-wheel drive vehicle, an axle shaft and a differential which are non-driving side during two-wheel drive are provided. There is a drive force connecting / disconnecting device that connects the differential side gear shaft and the axle shaft so that the drive force can be transmitted during four-wheel drive, and that disconnects the connection during two-wheel drive. The drive force connection / disconnection device prevents transmission of drive force from the non-drive side wheels to the propeller shaft side during two-wheel drive of the vehicle, and prevents unnecessary rotation of the rotating member from the propeller shaft to the transfer. It functions to reduce vibration noise caused by the drive system and to improve fuel efficiency, and is generally disclosed in JP-A-60-219.
As shown in Japanese Unexamined Patent Publication No. 124, it is configured as a dog clutch type.

[0003]

By the way, in the above-mentioned dog clutch type driving force connecting / disconnecting device, the tooth portions provided on the driving member and the driven member are meshed with each other to connect the both members. , An actuator for activating the clutch to engage these two members, a synchronizing means for synchronizing the rotation of these two members, a waiting mechanism for waiting the engagement until the mutual tooth portions are in an engageable state, and the like. Need a mechanism. For this reason, the size of the device itself is increased and the weight is increased, which is disadvantageous in terms of fuel consumption and mountability.

Therefore, the object of the present invention is to automatically connect the differential side gear shaft and the axle shaft so that the driving force can be transmitted during four-wheel drive, and automatically disconnect the connection during two-wheel drive. And a waiting mechanism for synchronizing the rotation of both an actuator, a driving member and a driven member by providing a driving force interrupting device for operating the interrupting mechanism required for a conventional driving force interrupting device. Etc. are to be abolished.

[0005]

SUMMARY OF THE INVENTION The present invention is arranged between a differential shaft and an axle shaft that is on the non-driving side when driving two wheels, and when driving four wheels, a side gear shaft of the differential gear and the axle shaft. Is a drive force connecting / disconnecting device in a four-wheel drive vehicle that connects the drive force transmission and the side gear shaft and the axle shaft during two-wheel drive, and disconnects the drive force transmission connection between the side gear shaft and the axle shaft. A support member fixed to the support member, a drive member rotatably supported by the support member and connected to the differential case of the differential to transmit a driving force, and the support member rotatably supported by the support member and the axle. It is connected to the shaft so that the driving force can be transmitted and maintains a predetermined circumferential distance on the outer circumference of the side gear shaft. A driven member positioned concentrically Te,
A first friction clutch that is provided between the drive member and the support member and frictionally engages when the drive member is driven; a pressing member that is provided on the outer periphery of the drive member so as to be movable in the axial direction; A second friction clutch that is provided between the side gear shaft and the driven member, is pressed by the pressing member and frictionally engages, and connects the side gear shaft to the driven member so that a driving force can be transmitted; A cam means provided between a member and the first friction clutch, which is operated when the first friction clutch rotates relatively to move the pressing member in the axial direction to frictionally engage the second friction clutch. It is characterized by having.

In the driving force connecting / disconnecting device, the friction clutch is actuated between the driven member and the second friction clutch when the second friction clutch is frictionally engaged with the pressing member. It is preferable to provide a second cam means for pressing.

[0007]

In the four-wheel drive vehicle drive force connecting / disconnecting device configured as described above, the first friction clutch does not rotate relative to each other when the drive member is not driven. Does not move to the clutch side. Therefore, the second friction clutch does not frictionally engage and the differential side gear shaft is not coupled to the driven member so as to be able to transmit the driving force. As a result,
When the vehicle is driven by two wheels, even if the driven member is rotated by the transmission of rotation from the axle shaft, the side gear shaft and the driving member are not rotated by this, and the drive system from the differential case of the differential gearbox is not rotated. Unnecessary driving is prevented, and loss of driving force and generation of vibration noise due to unnecessary driving of the drive system are prevented.

When the vehicle is switched to the four-wheel drive state in this state, the driving force input to the differential differential case is transmitted to the site gear shaft and the driving member, and the first friction is caused by the rotation of the driving member. The clutch rotates relative to actuate the cam means, move the pressing member toward the second friction clutch, and frictionally engage the friction clutch. As a result, the side gear shaft and the driven member are connected so that the driving force can be transmitted, and the driven member is driven by the side carrier shaft to rotate. This rotation is transmitted to the axle shaft connected to the driven member and the wheels to drive the wheels to drive the vehicle by four-wheel drive. Further, when the vehicle is switched to the two-wheel drive state, the transmission of the driving force to the differential case of the differential is stopped, so that the side gear shaft and the drive member stop rotating. In this state, the frictional engagement of the first friction clutch is released, and the pressing member moves away from the second friction clutch side and moves to the opposite side. Therefore, the frictional engagement of the second friction clutch is released, and the connection between the side gear shaft and the driven member capable of transmitting the driving force is cut off. Therefore, when the driven member stops rotating, the connection with the side gear shaft capable of transmitting the driving force is automatically cut off, and the vehicle is driven by two wheels.

In the drive connecting / disconnecting device, the friction clutch is actuated between the driven member and the second friction clutch when the second friction clutch is frictionally engaged to press the friction clutch against the pressing member. When the second cam means is provided, the second
When the friction clutch is frictionally engaged, the second cam means is actuated to lock up the friction clutch, so that the connection for transmitting the driving force between the side gear shaft and the driven member is made more reliable.

As described above, in the drive force connecting / disconnecting device, the connection between the side gear shaft and the driven member can be automatically transmitted when the four wheels are driven, and the connection is automatically cut off when the two wheels are driven. Therefore, the actuator for operating the interrupting mechanism, the synchronizing means for synchronizing the rotations of both the driven and driven members, the waiting mechanism, etc., which are required for the conventional drive force interrupting device, are not necessary, and all of them are abolished. can do.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 and FIG. 2 show a driving force connecting / disconnecting device 10 according to the present invention. The drive force connecting / disconnecting device 10 is a drive force connecting / disconnecting device for a four-wheel drive vehicle capable of switching between two wheels and four wheels, and as shown in FIG. 3, an axle shaft that is a non-drive side when the four-wheel drive vehicle 20 is driven by two wheels. It is placed between the differential and connects the side gear shaft of the differential and the axle shaft so that the driving force can be transmitted during four-wheel drive, and can transmit the driving force between the side gear shaft and the axle shaft during two-wheel drive. It functions to break the connection.

The four-wheel drive vehicle 20 has a transmission 21 connected to an engine (not shown) so as to be able to transmit driving force.
And a transfer 22 integrated with the transmission 21
One output shaft from the transfer 22 is always connected to the rear wheel side propeller shaft 23a, and the other output shaft from the transfer 22 is the front wheel side propeller shaft 2a.
It is intermittently connected to 3b. The rear wheel side propeller shaft 23a is connected to the rear wheel side axle shaft 25a via the rear wheel side differential 24, and the front wheel side propeller shaft 23b is connected to the front wheel side differential 26.
It is connected to the front wheel side axle shaft 25b via. The drive force connecting / disconnecting device 10 is a front wheel side differential 2
6 and one of the front wheel side axle shafts 25b.

As shown in FIGS. 1 and 2, the drive force connecting / disconnecting device 10 includes a first friction clutch 14, a first cam means 15, a piston 16a, and a second friction between the inner shaft 11, the support member 12 and the outer housing 13. The clutch 17 and the second cam means 18 are arranged. In this embodiment, the inner shaft 11 corresponds to the driving member of the present invention, and the outer housing 13 corresponds to the driven member. Inner shaft 11 and outer housing 13
Is rotatably supported by a support member 12, and the outer housing 13 is concentrically located on the outer circumference of the inner shaft 11 with a predetermined circumferential interval. The inner shaft 11 is relatively rotatably fitted to one outer circumference of the side gear shaft 26b, and is connected to one end of the differential case 26a of the differential gear 26 via a dog clutch so that torque can be transmitted. A pair of differential pinions 26e, which mesh with side gears 26d provided on both side gear shafts 26b, are supported by the differential case 26a.
The front wheel side propeller shaft 23b is attached to the differential case 26a.
Are connected via a drive pinion 26f and a ring gear 26g. One of the both side gear shafts 26b is connected to the left axle shaft 25b via the driving force interrupting device 10, and the other is connected to the right axle shaft 2b.
It is directly connected to 5b. The support member 12 is fixed to the diff carrier 26c, and the outer housing 13 is connected to one of the axle shafts 25b so that the driving force can be transmitted.

The first friction clutch 14 includes a pair of inner plates 14a and 14b and a pair of outer plates 14c and 14c.
14d, and the first inner plate 14a is spline-fitted to the outer periphery of the inner shaft 11 to form the same shaft 11a.
The second inner plate 14b is attached to the outer periphery of the inner shaft 11 so as to be slidable in the axial direction, and the second inner plate 14b is splined to the piston 16a. It is fitted and assembled so that it can slide in the axial direction. In addition, both outer plates 14c,
14 d is spline-fitted to the inner circumference of the support member 12 and is attached to the support member 12 so as to be slidable in the axial direction.

The first outer plate 14c is located between the inner plates 14a and 14b, and the second outer plate 14d is located between the second inner plate 14b and the retaining member 16b screwed to the support member 12. There is. The disc spring 16c includes the inner shaft 11 and the first inner plate 14.
The plate 14a is interposed between the a and the retaining member 16
It is biased to the b side with a predetermined force. As a result, the first friction clutch 14 is given a predetermined preload.

The second friction clutch 17 is a multi-plate clutch consisting of a large number of inner plates 17a and outer plates 17b, and each inner plate 17a is an inner shaft 1.
1 is spline-fitted to the outer circumference of the side gear shaft 26b penetrating 1 and the outer plates 17b are spline-fitted to the inner circumference of the inner sleeve 19, and are arranged alternately. The second friction clutch 17 has a stopper 16d screwed to the inner circumference of the outer housing 13 at one end side.
And the separator 16e allows the plates 17a, 1
The clearance between 7b is adjusted. Piston 16
a is between the separator 16e and the first inner plate 14a of the first friction clutch 14, via the thrust needle bearing 16f and the cosle spring 16g,
It is attached to the outer periphery of the inner shaft 11 so as to be slidable in the circumferential direction and the axial direction.

The first cam means 15 is the first friction clutch 14.
Is formed between the first inner plate 14a and the piston 16a, and the disc spring 16c urges both of them 14a, 16a into a cam engagement. The second cam means 18 is formed between an inner sleeve 19 and an outer housing 13 which are slidably attached to the inner circumference of the outer housing 13 in the circumferential direction and the axial direction. The inner sleeve 19 is a disc spring 16 hooked on the outer housing 13.
It is urged by h, and both 13 and 19 are cam-engaged.

In the vehicle provided with the driving force connecting / disconnecting device 10 thus constructed, the front wheel side propeller shaft 23b is in the non-driving state and the inner shaft 11 is in the non-rotating state during two-wheel drive. Therefore, the first friction clutch 14 does not rotate relative to each other, the first cam means 15 is in a non-operating state, and the piston 16a does not press the second friction clutch 17, so that the same friction clutch 17 is used.
Is not frictionally engaged, and the second cam means 18 is in the inoperative state. Therefore, the connection between the side gear shaft 26b and the outer housing 13 capable of transmitting the driving force is cut off, and there is no transmission of the driving force from the outer housing 13 of the axle shaft 25b to the side gear shaft 25b side and the differential case 26a side. The rotational force of the left front wheel 27b during the two-wheel running is not transmitted to the side gear shaft 26b side. Therefore, on the front wheel side, the side gear shaft 26b is rotated by the rotation of the right front wheel 27a, and the outer housing 13 is rotated by the rotation of the left front wheel 27b, but the inner case 11 is not rotated, so that the differential case 26a is rotated. Since the left side gear shaft 26b does not rotate, the front wheel side propeller shaft 23b does not rotate.

When the vehicle in such a state is switched to the four-wheel drive state, the front wheel side propeller shaft 23b is driven and the driving force is input to the differential case 26a of the differential 26, and the inner shaft 11 and each of the left and right side gear shafts 26b. Rotates to both left and right axle shafts 25b
To rotate. Therefore, in the drive force connecting / disconnecting device 10, the inner plates 14 a, 1 of the first friction clutch 14 are
Relative rotation is generated between 4b and the bottom plates 14c and 14d, and frictional engagement occurs, and relative rotation is generated between the first inner plate 14a and the piston 16a. As a result, the first
The cam means 15 operates to slide the piston 16a toward the second friction clutch 17 side, and the friction clutch 17 is frictionally engaged by the pressing force of the piston 16a, so that the second cam means 18 moves.
The side gear shaft 26b and the outer housing 13 are connected to each other via a drive force.

In this case, when the torque transmitted by the second friction clutch 17 overcomes the biasing force of the disc spring 16e, relative rotation occurs between the outer housing 13 and the inner sleeve 19, and the second cam means 18 operates, The cam surface of the inner sleeve 19 rides on the cam surface of the outer housing 14.
Therefore, the inner sleeve 19 has the second friction clutch 17
The friction clutch 17 is slid to the side and the retaining member 16d is removed.
A strong frictional engagement between and locks up. As a result, the inner shaft 11 and the outer housing 13 are connected to each other, and the connection capable of transmitting the driving force between the two is further strengthened, and the driving force of the side gear shaft 26b during four-wheel drive of the vehicle is increased. Is reliably transmitted to the left axle shaft 25b and the left front wheel 27b. As a result, the front wheels 27a and 27b are reliably driven by the driving force of the side gear shafts 26b.

On the other hand, when the vehicle in the four-wheel drive state is switched to the two-wheel drive state, the drive of the front wheel side propeller shaft 23b is stopped, so that the input of the driving force to the differential case 26a of the differential gear 26 is stopped and each side gear shaft is stopped. The transmission of the driving force to 26b is stopped. In this state, the inner plate 1 of the first friction clutch 14
The relative rotation between the outer plates 14a and 14b and the outer plates 14c and 14d is canceled, and the first cam means 15 is deactivated. As a result, the piston 16a moves to the second friction clutch 17
The frictional engagement of the friction clutch 17 is loosened to release the lockup state, and relative rotation is generated between the inner sleeve 19 and the outer housing 13. As a result, the riding state of both cam surfaces of the second cam means 18 is canceled, the pressing of the inner sleeve 19 and the piston 16a against the second friction clutch 17 is released, and the friction engagement state of the friction clutch 17 is released. It Therefore, the connection between the side gear shaft 26b and the outer housing 13 capable of transmitting the driving force is cut off, and the axle shaft 25
From the outer housing 13 of b to the side gear shaft 26
Since the driving force is not transmitted to the b side and the differential case 26a side, the rotational force of the front wheels 27a and 27b during the two-wheel running of the vehicle is not transmitted to the front wheel side propeller shaft 23b side.

As described above, in the drive force connection / disconnection device 10, when the vehicle is in the two-wheel drive state, the connection between the side gear shaft 26b and the outer housing 13 capable of transmitting the drive force is cut off, and the vehicle is connected to the four sides. When the vehicle is switched to the wheel drive state, the connection between the two 26b and 13 is automatically transmitted, and when the vehicle in this state is switched to the two-wheel drive state, the connection between the two 26b and 13 is automatically transmitted. Be shut off. Therefore, in the drive force connection / disconnection device 10, an actuator, a drive member, and an actuator for operating the connection / disconnection mechanism required by the conventional drive force connection / disconnection device for switching between the two-wheel drive state and the four-wheel drive state of the vehicle. It is possible to eliminate all the synchronizing means, the waiting mechanism, etc. for synchronizing the rotation of the driving member.

In this embodiment, the piston 16
The thrust needle bearing 16g is interposed between a and the separator 16e, and the coil spring 16g is interposed between the piston 16a and the inner shaft 11, so that the piston 16a, the stopper 16d, and the separator 16 are disposed.
By adjusting the position of e, the side gear shaft 26b is prevented from rotating by the rotation of the outer housing 13.

[Brief description of drawings]

FIG. 1 is a sectional view of a driving force interrupting device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of the driving force connecting / disconnecting device.

FIG. 3 is a schematic configuration diagram of a vehicle provided with a driving force connecting / disconnecting device according to the present invention.

[Explanation of symbols]

10 ... Driving force interrupting device, 11 ... Inner shaft, 12 ...
Support member, 13 ... Outer housing, 14 ... First friction clutch, 15 ... First cam means, 16a ... Piston, 17
... second friction clutch, 18 ... second cam means, 20 ... four-wheel drive vehicle, 25b ... axle shaft, 26 ... differential differential, 26a ... differential case, 26b ... side gear shaft, 26c ... differential carrier.

Claims (2)

[Claims] 1. A two-wheel drive is arranged between an axle shaft and a differential that are on the non-drive side, and a four-wheel drive connects the side gear shaft of the differential and the axle shaft so that driving force can be transmitted. In addition, it is a drive force connecting / disconnecting device in a four-wheel drive vehicle that disconnects the drive force transmittable connection between the side gear shaft of the differential and the axle shaft during two-wheel drive, and is fixed to the carrier of the differential. A support member, a drive member rotatably supported by the support member and connected to the differential case of the differential to transmit a drive force, and a drive member rotatably supported by the support member and a drive force by the axle shaft. The side gear shafts are communicatively connected to each other while maintaining a predetermined circumferential distance on the outer circumference of the side gear shaft. Driven member, a first friction clutch provided between the drive member and the support member and frictionally engaged when the drive member is driven, and an axially movable outer periphery of the drive member. A pressing member provided in
A second friction clutch which is provided between the side gear shaft and the driven member, is frictionally engaged by being pressed by the pressing member, and couples the side gear shaft to the driven member so that a driving force can be transmitted thereto; A cam that is provided between the pressing member and the first friction clutch and that operates when the first friction clutch rotates relatively to move the pressing member in the axial direction to frictionally engage the second friction clutch. A drive force connecting / disconnecting device in a four-wheel drive vehicle, comprising: 2. A first friction clutch, which is provided between the driven member and the second friction clutch and operates when the second friction clutch is frictionally engaged to press the friction clutch against the pressing member. 2. The drive force connection / disconnection device for a four-wheel drive vehicle according to claim 1, further comprising two cam means.