JP2002266982A - Differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform differential operation only when necessary. SOLUTION: This differential device comprises a differential mechanism 5 which has a plurality of pinion gears 33 and a pair of side gears 35, 37 on output side engaging with the pinion gears and distributes the driving force of an engine inputted to the pinion gear 33 from the respective side gears 35, 37 to wheel side, a frictional clutch 7 which restricts its differential rotation, a clutch means 9 which disengages the frictional clutch 7, an actuator 11 which axially reciprocates the clutch member 9 to control the disengagement of the frictional clutch 7, and a differential case 3 which rotates with the driving force from the engine inputted in a condition where the differential mechanism 5, the frictional clutch 7 and the clutch member 9 are stored.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device for distributing the driving force of an engine to left and right wheels.

[0002]

2. Description of the Related Art Generally, in a differential device used for a front-wheel drive or a four-wheel drive vehicle, it is necessary to consider an improvement in running performance and a reduction in torque steer. Torque steer is when the vehicle corners on the road surface,
This is a phenomenon in which the differential of the differential device acts too much and the steering wheel cuts more than the driver's will. Therefore, it is necessary to reduce the differential limiting force of the differential device in order to reduce the torque steer. On the other hand, when the differential limiting force of the differential device is reduced, the running performance is reduced. Conventionally, the strength of a differential device has been controlled by hydraulic pressure in order to achieve both such torque steer and running performance.

FIG. 3 shows a conventional differential device described in Japanese Patent Application Laid-Open No. 3-282035 for controlling by hydraulic pressure.

[0004] The differential device 101 has a transaxle case 10 on both left and right sides via bearings 105.
7 is provided with a differential case 103 rotatably held. The differential case 103 is rotated by driving the engine when the ring gear 109 to which the rotational driving force from the engine is input is fixed.

The differential case 103 has a pinion shaft 1
11 is fixed, and a pair of pinion gears 113 are rotatably supported on the pinion shaft 111. The pinion gear 113 has left and right side gears 11 on the output side.
5, 117 are engaged with each other, and the left and right side gears 11 are engaged.
5, 117 are spline-connected to left and right axles 119, 121, respectively.

The rotation of the differential case 103 is performed by rotating the pinion shaft 111 and the pinion gear 113 from the side gear 11.
5, 117 to the left and right axles 119, 121. When a difference occurs between the driving resistances of the left and right axles 119 and 121, the pinion gear 113 rotates and the rotation is differentially distributed to the left and right.

The left side gear 115 and the differential case 10
3, a multi-plate clutch 123 connecting these components is arranged. When the multiple disc clutch 123 is engaged, the rotation of the pinion gear 113 is restricted according to the engagement force, and the differential of the differential mechanism 125 is restricted.

A hydraulic mechanism 127 is disposed adjacent to the multi-plate clutch 123 to control the engagement of the multi-plate clutch 123. The hydraulic mechanism 127 includes a cylinder 129 and a piston 131 that slides in the cylinder 129 toward the multi-plate clutch 123 to press the multi-plate clutch 123. Further, the cylinder 129 is connected to a pressure source and a control valve mechanism via an oil passage 133 to supply the differential oil.

The differential limitation by the hydraulic mechanism 127 is manually operated from a driver's seat or automatically operated according to steering conditions or road surface conditions. Then, for example, when one of the wheels is in an idling state while traveling on a rough road, if the multi-plate clutch 123 is engaged, the driving force is sent to the other wheel by the differential limiting mechanism, and the vehicle travels. Can continue. When the multi-plate clutch 123 is engaged in this manner, the differential between the left and right wheels is limited, so that the straight traveling property during traveling is improved (improved running performance).

When the multi-plate clutch 123 is released, the differential between the left and right wheels becomes free, and the vehicle can perform smooth cornering (reduction of torque steer). Also,
Straight running stability on uneven roads is improved.

[0011]

In such a structure in which the multi-plate clutch 123 is fastened by the hydraulic mechanism 127, since the differential oil is supplied to the cylinder 129, the startup of the fastening is poor. I have. In such a case where the rise of the fastening is poor, the differential between the left and right wheels is delayed, which may affect the traveling performance on a rough road or the like.

Further, it is necessary to provide a hydraulic line for supplying the differential oil to the cylinder 129, which complicates the structure. Moreover, this hydraulic line is a differential case 103
It is necessary to provide not only a structure that can supply differential oil without being affected by rotation, but also a structure that prevents oil leakage, because it is provided inside a rotating rotating system such as There is a problem that the structure is complicated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a differential device which can be quickly assembled and has a simple structure.

[0014]

According to a first aspect of the present invention, there is provided a differential device including a plurality of pinion gears and a pair of output side gears meshed with the plurality of pinion gears. A differential mechanism distributed to the wheel side, a friction clutch for limiting the differential rotation thereof, a clutch member for connecting and disconnecting the friction clutch, an actuator for controlling the connection and disconnection of the friction clutch by reciprocating the clutch member in the axial direction, A differential case is provided in which a differential mechanism, a friction clutch, and a differential case that rotates by receiving driving force from the engine in a state in which the clutch member is accommodated are provided.

When the actuator has disengaged the clutch member from the friction clutch, the differential between the left and right wheels is free, and the driving force of the engine is input to the differential case and is output from the pinion gear via the output side gear. Since it is distributed to each wheel side, the traveling performance of normal traveling can be improved.

On the other hand, when the actuator operates the clutch member to fasten the friction clutch, the friction clutch automatically limits the differential due to the reaction force between the pinion gear and the side gear. Therefore, even if one of the wheels slips on a derailed road or a rough road, the friction clutch can be pressed by the meshing reaction force of the side gears to obtain a differential limiting function. Can be improved.

Further, since the engagement of the friction clutch is performed by moving the clutch member under the control of the actuator, the rise of the engagement is fast, and the rise of the differential limit is fast.

Further, not only is the hydraulic line unnecessary, but also there is no need to worry about leakage of differential oil in the rotating system, so that the structure can be simplified.

According to a second aspect of the present invention, there is provided the differential device according to the first aspect, wherein the actuator and the clutch member are disposed on opposite sides of the axial center of the differential case. Claim 1
The same operation and effect as those of the above configuration can be obtained.

Further, by arranging in this manner, the center of the differential case can be aligned with the center of the differential device. Therefore, the left and right lengths of the differential device can be made substantially the same, and the balance is improved.

According to a third aspect of the present invention, there is provided the differential device according to the first or second aspect, further comprising a detent portion which engages with the differential case to detent, and the clutch member and the actuator are connected to each other. It further includes a connecting member for connecting, and the detent portion is located near the clutch member, and the same operation and effect as the configuration of claim 1 or 2 can be obtained.

According to the present invention, when the coupling member connects the clutch member and the actuator, the detent portion of the coupling member serves as a torque transmission path. Since the detent portion of the connecting member is located near the clutch member, the torque transmission path is shortened, and the responsiveness can be improved.

Further, since the torque transmission path is shortened, no extra force is applied to the connecting member during connection. For this reason, it is not necessary to make the connecting member stronger than necessary.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A differential device 1 according to a first embodiment of the present invention will be described with reference to FIG. The differential device 1 has the features of the first, second, and third aspects. The left and right directions are the left and right directions in FIG. 1, and the members and the like without reference numerals are not shown.

The differential device 1 comprises a differential case 3, a bevel gear type differential mechanism 5, a multi-plate clutch 7 (friction clutch), a clutch member 9, an actuator 11, and the like.

The differential case 3 has a cover 21 and a case body 23 fastened by bolts 25, and is entirely disposed inside the differential carrier. Differential case 3
Includes a cover 21 and a case body 23 fastened by bolts 25.

The differential case 3 has left and right boss portions 27 and 29 rotatably supported by a differential carrier by bearings. Further, a ring gear is fixed to the differential case 3, and a drive pinion gear meshing with the ring gear is connected to the engine through a power transmission system, and the differential case 3 is driven to rotate by the driving force of the engine. The rotation of the differential case 3 is transmitted to the pinion shaft 31,
Input to the differential mechanism 5.

The differential mechanism 5 includes a plurality of pinion shafts 3.
1, a pinion gear 33 rotatably supported on each pinion shaft 31, and output side gears 35 and 37 meshing with the respective pinion gears 33 from the left and right.

The plurality of pinion shafts 31 are arranged at equal intervals in a direction orthogonal to the rotation direction. Each of the pinion shafts 31 is pressed into the differential case 3 to rotate integrally with the differential case 3.

The side gears 35 and 37 are spline-connected to the axle via respective bosses 35a and 37a, and are connected to the left and right wheels via the respective axles.

The multi-plate clutch 7 is arranged between the inner periphery of the differential case 3 and the outer periphery of one boss 35a (side gear 35). Outer plate 39 of multi-plate clutch 7
Is engaged with the clutch member 7 and the inner plate 4
Numeral 1 is engaged with a ring-shaped leg 43 welded to the boss 35a. Note that the leg 43 is provided with a stopper 45 for preventing the axial movement of the multi-plate clutch 7 toward the actuator 11.

The clutch member 9 has a cylindrical shape and is arranged between the multi-plate clutch 7 and the differential case 3.
A radial dog clutch 9a is formed on the right end surface (the actuator 11 side) of the clutch member 9. The right side of the clutch member 9 is penetrated by the pinion shaft 31 and is in contact with the outer end surface of the pinion washer 63, whereby the clutch member 9 is positioned.

On the right side of the clutch member 9, the case body 2
A connecting member 47 extending from the inside of the housing 3 to the outside of the right side of the case body 23 is disposed. The left end face of the connecting member 47a
The dog clutch 47 is engaged with the dog clutch 9 a of the clutch member 9.
a is formed. These dog clutches 9a, 47
The tooth "a" is formed so as to be tapered and inclined toward the other side so that the teeth can be easily meshed. This dog clutch 47
is engaged with the dog clutch 9a, the coupling member 47 is coupled to the clutch member 9, and the actuator 11
And the clutch member 9 are connected via the connecting member 47.

On the side surface of the connecting member 47 on the case body 23 side, there are formed non-rotating teeth 47b made of splines, and on the inner surface of the case body 23 corresponding thereto, engaging teeth 23b made of splines are formed. Have been. When the non-rotating teeth 47a engage with the engagement teeth 23b and the dog clutches 9a, 47a bite, the connecting member 47 transmits the rotation of the differential case 3 to the clutch member 9.

The non-rotating teeth 47b are connected to the clutch member 9
Is formed on the connecting member 47 so as to be located in the vicinity of. Thereby, the torque transmission path for transmitting the rotational force of the differential case 3 is shortened, and the responsiveness is improved.

The actuator 11 moves the connecting member 47 in the axial direction by a fluid pressure such as air pressure or hydraulic pressure.
Is located on the right outside.

The actuator 11 driven by fluid pressure is
The bracket 51 includes an actuator main body 53 fixed to a differential carrier, and a retainer 55 for connecting the actuator main body 53 and the connecting member 47. A pressure chamber 53 a is formed inside the actuator body 53, and this pressure chamber 53 a is connected to an external pressure source via a flow path 57. A connecting member 47 is provided between the retainer 55 and the case body 23 by the dog clutch 9.
A return spring 59 is provided to urge in the anti-meshing direction of a and 47a.

In this embodiment, the actuator 11 and the clutch member 9 connected by the connecting member 47 are
The differential case 3 is located on the opposite side to the axial center (diff center) 61. By arranging in this manner, the differential center 61 can be aligned with the central portion of the differential device 1, and the differential device 1
Can have substantially the same length. For this reason,
Improves balance.

When the actuator 11 is not operated, the connecting member 4 and the clutch member 9 are not connected, and in this state, the differential between the left and right wheels is free. Accordingly, the driving force of the engine is input to the differential case 3, and the output side gears 35, 3 are transmitted from the pinion gear 31 to the output side.
The wheels are distributed to the respective wheel sides via the normal driving wheels 7 and normal traveling is performed.

On the other hand, when the actuator 11 operates and the connecting member 47 bites into the clutch member 9, the differential case 3 and the clutch member 9 are connected via the connecting member 47, and the rotational force of the differential case 3 is reduced by the connecting member 47. , The clutch member 9 and the multi-plate clutch 7 are input to the side gear 35. At this time, the multi-plate clutch 7 automatically limits the differential due to the meshing reaction force between the pinion gear 31 and the side gears 35 and 37. Therefore, even if one of the wheels slips on a slipping road or a bad road, the multiple disc clutch 7 can be pressed by the meshing reaction force of the side gear 35 to obtain a differential limiting function, and the slipping out of the slipping or bad slippage can be obtained. Road running performance can be improved.

The engagement of the multi-plate clutch 7 is performed by the movement of the clutch member 9 under the control of the actuator 11, so that the rise of the engagement and the rise of the differential limit become earlier. Further, a hydraulic line for fastening the multi-plate clutch 7 is not required, and there is no fear of leakage of differential oil, so that the structure can be simplified.

The non-rotating teeth 47b of the connecting member 47
Is provided so as to be located near the clutch member 9, and the torque transmission path for transmitting the rotational force of the differential case 3 is shortened, so that the responsiveness is improved. Since the torque transmission path is shortened in this way, no extra force is applied to the connecting member 47 at the time of connection, and it is not necessary to make the connecting member 47 stronger than necessary.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention. The outer plate 39 of the multiple disc clutch 7 is engaged with the clutch member 9. This clutch member 9 has a shape extending along the moving direction of the connecting member 47. The connecting member 47 is movable so as to overlap in the length direction of the clutch member 9. In the overlapping portion of the connecting member 47 in the clutch member 9, the connecting member 4
The spline-shaped connecting teeth 65 with which the 7 non-rotating teeth 47b are engaged are formed. The non-rotating teeth 47b engage with the coupling teeth 65 of the clutch member 9 while being engaged with the engaging teeth 23b of the case body 23.

In this embodiment, when the connecting member 47 is moved in the direction of the multi-plate clutch 7 by the operation of the actuator 11, the detent teeth 47b are fitted into and engaged with the connecting teeth 65 of the clutch member 9. Thereby, the connecting member 4
7, the actuator 11 and the clutch member 9 are connected. Therefore, since the connection and disconnection of the multi-plate clutch 7 is performed by the connecting member 47, the same operation as in the first embodiment can be performed.

[0045]

According to the first aspect of the present invention, since the friction member is engaged by moving the clutch member by the actuator, the rise of the engagement is fast and the rise of the differential limit is fast. In addition, no hydraulic line is required, and there is no need to worry about leakage of differential oil, so that the structure can be simplified.

According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained. In addition, since the center of the differential case can be aligned with the center of the differential device, the balance of the differential device can be improved. Can be improved.

According to the invention of claim 3, claims 1 and 2
In addition to obtaining the same effect as the invention of the above, the detent portion of the connecting member is located near the clutch member, so that the torque transmission path is shortened and the responsiveness is improved, and the connecting member is unnecessarily increased. There is no need to be strong.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of a second embodiment.

FIG. 3 is a sectional view of a conventional differential device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Differential device 3 Differential case 5 Differential mechanism 7 Multi-plate clutch 9 Clutch member 11 Actuator 31 Pinion shaft 33 Pinion gear 35, 37 Side gear 47 Connecting member

Claims (3)

[Claims] 1. A differential mechanism having a plurality of pinion gears and a pair of output side gears meshing with the pinion gears, and distributing a driving force of an engine input to the pinion gears from each side gear to a wheel side, and a differential mechanism. A friction clutch that limits dynamic rotation, a clutch member that connects and disconnects the friction clutch, an actuator that controls the connection and disconnection of the friction clutch by reciprocating the clutch member in the axial direction, a differential mechanism, a friction clutch, and a clutch member are housed. A differential case that is rotated by receiving driving force from the engine in a state. 2. The differential device according to claim 1, wherein the actuator and the clutch member are disposed on opposite sides of a center of the differential case in the axial direction. 3. The differential device according to claim 1, further comprising: a detent member that engages with the differential case to detent and connects the clutch member and the actuator. A differential device, further comprising: a detent portion located near a clutch member.