JP2003184991A - Differential gear device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent loss of differential limiting force caused by an energizing means for initial torque and to improve building-up of the differential limiting force. <P>SOLUTION: The differential gear device is provided with a differential mechanism 5 which outputs rotation of a differential case 3 rotated by an engine to the outside from side gears 29, 31, pressing members 7, 7 connected to the wheel side, friction clutches 11, 11 provided between the differential case 3 and the pressing members 7, 7, cam means 9, 9 which are provided between the side gears 29, 31 and the pressing members 7, 7, are operated by receiving the torque, and press the friction clutches 11, 11 via the pressing members 7, 7, and the energizing means 13, 13 which are arranged between the side gears 29, 31 and the pressing members 7, 7, press the friction clutches 11, 11 via the pressing members 7, 7, and impart the initial torque. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device having a constant differential limiting force due to an initial torque imparting function of a biasing means.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 9-89086 discloses a differential device 201 as shown in FIG.

The differential device 201 comprises a differential case 203, a bevel gear type differential mechanism 205, a pair of multi-plate clutches 207, 207, disc springs 209, 209 and the like.

The differential mechanism 205 has a differential case 20 at both ends.
The pinion shaft 211 is connected to the pinion shaft 211, the pinion gear 213 is supported on the pinion shaft 211, and the pair of output side gears 215 and 217 are meshed with the pinion gears 213.

The side gears 215 and 217 are attached to the axle 21.
It is connected to each wheel side via 9, 221.

The driving force of the engine is transmitted from the drive pinion gear 223 through the ring gear 225 to the differential case 203.
And the rotation of the differential case 203 is performed by rotating the side gear 2 from the pinion shaft 211 via the pinion gear 213.
15 and 217, and transmitted from the axles 219 and 221 to each wheel side.

The multi-plate clutches 207, 207 are arranged between the differential case 203 and the side gears 215, 217, respectively, and are engaged by receiving the meshing thrust force of each side gear 215, 217.

Since the meshing reaction force of the side gears 215 and 217 increases in proportion to the transmission torque, when each multi-plate clutch 207 is engaged, the friction resistance of the multi-plate clutch 207 provides a torque-sensitive type differential limiting function, resulting in a differential. The differential rotation of the mechanism 205 is limited, and especially when the vehicle is started or accelerated with a large driving force, the startability, acceleration, maneuverability, and stability are improved.

However, under the condition that the drive wheels tend to idle, such as on a rough road, in the case of the torque sensitive type differential limiting mechanism, the differential limiting function deteriorates due to the escape of torque from the idle wheels, and the required difference is obtained. You can't get the motion restriction.

Therefore, it is necessary to apply the initial torque (constant differential limiting force) by the preload means.

The disc spring 209, which is the preload means, is arranged between each multi-plate clutch 207 and the differential case 203, and each multi-plate clutch 207 is connected to the side gears 215, 2.
It is pressed to the 17 side to give the initial torque.

[0012] For example, when one of the driving wheels tries to largely idle when the vehicle starts or accelerates, or on a bad road, the driving torque is sent to the grip side wheels by the initial torque of each multi-plate clutch 207. The ability to drive on rough roads is maintained at a high level, and the starting performance and acceleration performance are improved.

[0013]

However, in the differential device 201, the disc spring 209 has the disc spring 209.
3 and each multi-disc clutch 207 (multi-disc clutch 207
Of the side gears 215,
The direction of the meshing reaction force of 217 and the direction of the pressing force of the disc spring 209 are opposite.

In such a structure, the side gears 215,
While the flexure of the disc spring 209 is being advanced (increased) by the meshing reaction force of 217, the meshing reaction force is absorbed by this flexure, so that the multi-plate clutch 207 cannot be strongly pressed and the disc spring 209 When the flexure of No. 2 is completed, the multi-plate clutch 207 is first pressed by the differential case 203 and the differential limiting force rises.

As described above, in the differential device 201, the side gears 215, 2 are caused by the bending of the disc spring 209.
The meshing reaction force of 17 (pressing force of the multi-plate clutch 207: differential limiting force) causes a loss, and the differential limiting force rises slowly.

In FIG. 3, the vertical axis and the horizontal axis are the coordinates of the right axis torque and the left axis torque, respectively, and the magnitude of the driving torque (torque) transmitted to the right wheel by the differential limiting force when the left wheel idles. It is a graph showing distribution characteristics: torque bias ratio.

The graph 251 shows the differential device 2
01 indicates the characteristics when the biasing means presses the friction clutch from the direction opposite to the meshing reaction force of the side gear (cam thrust force of the cam means) (external push type: series type). The characteristic is shown when the meshing reaction force of the biasing means and the side gear (cam thrust force of the cam means) presses the friction clutch in the same direction (internal push type: parallel type).

Further, Ti is an initial torque by the biasing means, and a graph 301 having a slope of 45 ° shows the torque bias ratio of the differential device having no differential limiting function.

The portion 253 of the graph 251 is the characteristic until the meshing reaction force of the side gears 215 and 217 presses the multi-plate clutch 209 toward the differential case 203 side while bending the disc spring 209 as described above. After that, the graph 251 rises with a gradient like the portion 255.

As shown in the graph 251, in the case of the external push type, the rising of the differential limiting force (the portion 253) is gradual, and the generation of the differential limiting function is delayed for a moment, so that the rough road running performance, starting performance, The effects of improving acceleration, maneuverability and stability are insufficient.

The left wheel spins idle and its axial torque is T
The drive torque sent to the right wheel when it decreases to L is
The outer push type has a TR1, and the inner push type has a larger TR2.

The difference (TR2-TR1) is the above-mentioned loss, and the effect of improving maneuverability and stability at the time of starting or accelerating is reduced accordingly.

Since the differential limiting force on the graph 151 is larger than the differential limiting force on the graph 251 by this difference (TR2-TR1), the torque sent to the other wheel when one wheel idles. It will be that much larger, and the effect of improving maneuverability and stability when starting or accelerating will be further improved.

Further, as is well known, if the initial torque is excessively increased, a tight corner braking phenomenon may occur when the vehicle makes a sharp turn at a low speed or when the vehicle is put in a garage in which forward and backward movements are repeated while operating a large steering angle. , An abnormal sound may be generated due to this.

In the external push type in which the meshing reaction force of the side gear and the pressing force of the spring are pressed in opposite directions, the direction and the strength of the meshing reaction force of the side gear fluctuate greatly when the vehicle turns suddenly or is put into the garage. The balance between the urging force of the means and the meshing reaction force (the pressing force applied to the friction clutch) also fluctuates, and the tight corner braking phenomenon and abnormal noise are likely to occur.

The disc spring 209 has side gears 215 and 215.
Since the expansion and contraction are repeated due to the meshing reaction force of 217, the spring characteristics and the initial torque are likely to change, and the durability of the disc spring 209 is reduced.

Therefore, an object of the present invention is to provide a differential device in which loss of the differential limiting force by the biasing means for the initial torque is prevented and rising of the differential limiting force is improved.

[0028]

According to another aspect of the present invention, there is provided a differential device including: a differential case that rotates by receiving a driving force of a prime mover; and a differential mechanism that distributes the rotation of the differential case to the outside from a pair of output side gears. A pressing member connected to the wheel side, a friction clutch for limiting a differential provided between the differential case and the pressing member, and provided between the side gear and the pressing member, actuated by receiving torque, A cam means for pressing the friction clutch via a pressing member, and a biasing means arranged between the side gear and the pressing member for pressing the friction clutch via the pressing member to give an initial torque. It is characterized by that.

The driving force of the prime mover is distributed from the pinion gear of the differential mechanism to the output side gear, and is transmitted to the wheel side via the cam means and the pressing member.

At this time, a meshing reaction force is generated in the side gear due to meshing with the pinion gear, and the cam means is actuated by receiving the transmission torque between the side gear and the pressing member, and the friction clutch is actuated by the meshing reaction force and the cam thrust force. Are pressed and fastened by and to restrict the differential of the differential mechanism.

The meshing reaction force of the side gears and the cam thrust force of the cam means become larger as the transmission torque becomes larger, and a torque sensitive differential limiting function is obtained by the friction resistance of the friction clutch, so a large driving force is applied. The vehicle's startability, acceleration, maneuverability, and stability are improved during times and accelerations.

Further, an initial torque is applied to the friction clutch by an urging means, and when one of the drive wheels tries to idle at the time of starting, accelerating, traveling on a rough road, etc., the initial torque is applied to the grip side. Since the driving force is sent to the wheels, it is possible to prevent deterioration of running performance on rough roads, starting performance, acceleration performance, maneuverability, and stability.

The differential device of the present invention is
By providing the urging means between the side gear and the pressing member, the urging force of the urging means presses the friction clutch (in the same direction) in parallel with the cam thrust force of the cam means and the meshing reaction force of the side gears. As shown in the graph 151 in FIG. 3, since the differential limiting force due to the cam thrust force of the cam means and the meshing reaction force of the side gears does not cause an instant rise delay, the vehicle is startable, accelerating, and maneuverable. The properties, stability, etc. can be sufficiently improved.

Further, unlike the conventional example, since the loss of the differential limiting force due to the biasing means does not occur, as shown by the difference (TR2-TR1) between the graph 151 and the graph 251, one wheel is idling. When this is done, the torque sent to the other wheel is increased, and the startability, acceleration, maneuverability, stability, etc. are further improved.

Further, since the urging means does not receive the cam thrust force of the cam means and the meshing reaction force of the side gears, the characteristic (spring constant) is prevented from deteriorating and the pressing characteristic (initial torque) of the friction clutch is stabilized. The durability of the biasing means is greatly improved.

Further, because of the inward push type, the balance fluctuation between the urging force of the urging means and the cam thrust force of the cam means and the meshing reaction force is caused even during a sharp turn or garage entry.
The fluctuation of the pressing force of the friction clutch due to this balance fluctuation is reduced, and the tight corner braking phenomenon and the accompanying abnormal noise are also reduced.

According to a second aspect of the present invention, in the differential device according to the first aspect, the biasing means is arranged in a gap formed by the cam means between the side gear and the pressing member. The feature is that the same action and effect as those of the first aspect can be obtained.

In addition to this, a gap (existing space) formed between the side gear and the pressing member by the cam means.
By arranging the biasing means in the space, the use efficiency of the space is improved, and it is not necessary to change the internal structure or layout to provide the space for disposing the biasing means
It is possible to configure the differential device as an internally pressed type at low cost.

Further, since the side gear and the pressing member are connected by the cam means and a large relative rotation does not occur, the biasing means arranged between them is released from abrasion due to sliding and the biasing means is also provided. Since it is arranged between the side gear and the pressing member, interference with peripheral members such as gears is prevented, and wear and damage are avoided,
A change in spring constant and a decrease in durability are prevented, and a normal initial torque can be obtained for a long period of time.

Further, since the biasing means and the cam means can be arranged in the radial direction so as to overlap each other (they are arranged in the radial direction), the differential device is only that much in comparison with the structure in which they are arranged in the axial direction. It is made compact in the axial direction, improving the vehicle mountability.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A differential device 1 (one embodiment of the present invention) will be described with reference to FIGS. The left and right directions are the left and right directions in FIG. 1, and members and the like without reference numerals are not shown.

The differential device 1 includes a differential case 3, a bevel gear type differential mechanism 5, left and right pressing members 7,
7, left and right cams 9, 9 (cam means), left and right multi-plate clutches 11, 11 (friction clutch), left and right disc springs 13, 1
3 (biasing means) and the like.

The differential device 1 is arranged inside a differential carrier, and the differential carrier is provided with an oil reservoir.

The differential case 3 includes the left and right covers 15 and 17
The left cover 15 is fixed to the left opening of the casing body 19 with bolts, and the right cover 17 is welded to the right opening of the casing body 19. The boss portion 21 of the cover 15 and the boss portion 2 of the cover 17
3 are respectively supported by the differential carrier via bearings.

A ring gear is fixed to the differential case 3 with bolts, and this ring gear meshes with the output side gear of the power transmission system. This power transmission system is connected to the transmission side, and the differential case 3 is rotationally driven by the driving force of the engine (motor) transmitted via the transmission and this power transmission system.

The differential mechanism 5 comprises a plurality of pinion shafts 25, pinion gears 27 supported on the respective pinion shafts 25, and output side gears 29 and 31 meshing with the pinion gears 27 from the left and right. There is.

The pinion shafts 25 are arranged radially around the hub 33 formed integrally and at equal intervals in the circumferential direction. As shown in FIG. 2, the casing body 19
A spline 35 is formed on the inner periphery of the through the left opening to the right opening, and a spline 37 is provided at the tip of each pinion shaft 25. Each pinion shaft 25 is connected to the casing main body 19 so as to be movable in the axial direction by the engagement of the splines 37 and 35.

Between the casing body 19 and the pinion gear 27, the centrifugal force of the pinion gear 27 and the side gear 2
Pinion gear 27 generated by meshing with 9, 31
A spherical washer 39 is arranged to receive the meshing reaction force.

The left pressing member 7 is disposed on the axially outer side (left side) of the side gear 29, and is connected to the left wheel side via a splined axle. The right pressing member 7 is arranged on the axially outer side (right side) of the side gear 31, and is connected to the right wheel side via a spline-connected axle.

The hub portion 41 of the left pressing member 7 is the cover 15
Is supported by the support portion 43 of the left side gear 2
9 is supported on the outer periphery of the hub portion 41. The hub portion 45 of the right pressing member 7 is supported by the support portion 47 of the cover 17, and the right side gear 319 is supported on the outer periphery of the hub portion 45.

The left cam 9 is formed between the left side gear 29 and the pressing member 7, and the right cam 9 is formed between the right side gear 31 and the pressing member 7.

The left multi-plate clutch 11 is the casing body 1.
9 and the left pressing member 7 (hub portion 41), and the right multi-plate clutch 11 is arranged between the casing body 19 and the right pressing member 7 (hub portion 45). .

Outer plate 4 of each multi-plate clutch 11
9 is connected to the spline 35 of the casing body 19, and the inner plate 51 is connected to the pressing members 7 (the hub portion 4).
1, 45) are connected to splines 53, 53 formed on the outer periphery of the (1, 45).

The left disc spring 13 is arranged between the left side gear 29 and the pressing member 7, and the right disc spring 13 is arranged between the right side gear 31 and the pressing member 7. The left and right disc springs 13 utilize the gaps (spaces) formed by the left and right cams 9, respectively, and are arranged radially inside thereof.

The left disc spring 13 presses the left multi-plate clutch 11 via the pressing member 7, and the right disc spring 13 presses the right multi-plate clutch 11 via the pressing member 7, respectively. An initial torque irrelevant to the differential torque or the differential rotation speed is applied to generate a constant differential limiting force.

The driving force of the engine for rotating the differential case 3 is distributed to the left and right side gears 29 and 31 via the pinion shafts 25 and the pinion gears 27, and the cam 9 and the pressing member 7 and the axle are respectively distributed. It is transmitted to the left and right wheel side via.

Further, when a differential rotation or a drive resistance difference occurs between the left and right wheels at the time of starting, accelerating, running on a rough road, etc., the driving force of the engine is differentially moved to the left and right sides by the rotation of the pinion gear 27. Will be distributed.

Further, while the vehicle is traveling, the cams 9 and 9 are actuated by receiving the transmission torque between the side gears 29 and 31 and the respective pressing members 7 and 7 in both forward traveling and reverse traveling. The cam thrust force presses the multi-plate clutches 11 and 11 via the pressing members 7 and 7 to engage them.

Further, the meshing thrust force of the side gears 29 and 31 generated by the meshing with the pinion gear 27 presses the multi-plate clutches 11 and 11 via the pressing members 7 and 7 during both forward running and reverse running.

The cam 9, which increases in proportion to the transmission torque,
When the multi-plate clutches 11 and 11 are engaged by the cam thrust force of 9 and the meshing reaction force of the side gears 29 and 31, the friction resistance of the multi-plate clutches 11 provides a torque sensitive type differential limiting function, and the differential mechanism 5 has a differential mechanism. Is limited.

At the time of starting or accelerating when a large driving force is applied to the differential device 1, a large differential limiting force can be obtained by the torque-sensitive differential limiting function, so that the starting ability, acceleration ability, maneuverability and stability are improved. improves.

Further, since the initial torque is applied to the multi-disc clutches 11 and 11 by the disc springs 13 and 13 as described above, it is possible to start the vehicle, accelerate the vehicle, or run on a rough road. Even under the condition that one wheel runs idly and the torque sensitive differential limiting function deteriorates, due to the constant differential limiting force obtained by this initial torque,
Deterioration of startability, acceleration, running on rough roads, etc. is prevented, the behavior of the vehicle body is stabilized, and maneuverability is greatly improved.

A graph 151 in FIG. 3 shows the torque distribution characteristic of the internal push type differential device 1.

As described above, the differential device 1
Is an internal push type (parallel type) by the disc springs 13, 13 pressing the multi-plate clutches 11, 11 in parallel with the cam thrust force of the cams 9, 9 and the meshing reaction force of the side gears 29, 31. The cam thrust force and the meshing reaction force are not absorbed by the flexure of the disc springs 13 and 13, and the differential limiting force is not lost.

Therefore, as shown by the graph 151, unlike the conventional push type (graph 251), the differential limiting force instantly rises and no delay occurs.

Further, the differential case 3 is provided with an opening, and spiral oil grooves are provided on the inner circumferences of the boss portions 21 and 23. The oil in the oil sump is in the differential case 3.
As they rotate, they flow into and out of the differential case 3 through these openings and oil grooves, and the multi-plate clutches 11, 11, the cams 9, 9,
Bearings 43 and 47 of the pressing members 7 and 7, pressing members 7 and 7
(Hub portions 41, 45) and side gears 29, 31 sliding portions, gears 27, 29, 31 meshing portions, pinion shaft 25 and pinion gear 27 sliding portions, spherical washer 39, splines 35, 37. Is fully lubricated and cooled to improve durability.

Thus, the differential device 1 is constructed.

As described above, the differential device 1
Is configured as an internal push type in which the disc springs 13 and 13 press the multi-plate clutches 11 and 11 in parallel with the cam thrust force of the cams 9 and 9 and the meshing reaction force of the side gears 29 and 31.
As shown in the graph 151, when the driving torque or the differential torque is applied, the differential limiting force instantly rises, so that the maneuverability and stability of the vehicle are greatly improved especially at the time of starting or accelerating where a large driving torque is applied. .

Moreover, even if one of the wheels tries to idle,
Since the driving force is sent to the grip side wheels by the initial torque given to the multi-plate clutches 11 and 11 by the disc springs 13 and 13, the running performance on rough road, the starting performance and the acceleration performance are kept high.

Further, unlike the conventional example of the external push type,
Since the loss of the cam thrust force of the cams 9 and 9 and the meshing reaction force of the side gears 29 and 31 due to the flexure of the disc springs 13 and 13 does not occur, when one wheel idles to the other wheel as shown in the graph 151. The driving torque is increased, and the driving performance on rough roads, starting performance, acceleration performance, maneuverability, and stability are improved accordingly.

Further, since each pinion shaft 25 is axially movable with respect to the differential case 3 by the engagement of the splines 35 and 37, the cam thrust force of the left cam 9, the meshing reaction force of the side gear 29, and the disc spring 13 are provided. Biasing force, cam thrust force of the right cam 9 and side gear 31
Even if there is an imbalance between the meshing reaction force of B and the urging force of the disc spring 13 and the differential limiting forces of the left and right multi-plate clutches 11 are also unbalanced, the pinion shafts 25 move in the axial direction. Imbalance of is averaged,
An equal differential limiting force can be obtained with the left and right wheels.

Therefore, for example, the straightness of the vehicle is improved at the time of starting and accelerating, the behavior of the vehicle body is further stabilized, and the maneuverability is greatly improved.

The inward-pressing type disc springs 13 and 13 do not receive the cam thrust force of the cams 9 and 9 and the meshing reaction force of the side gears 29 and 31, and the side gears 29 and 31 and the pressing members 7 have the cam 9. , 9 so that a large relative rotation does not occur, the disc spring 13 arranged between them is released from abrasion due to sliding between the side gears 29, 31 and the pressing members 7.

Furthermore, the disc springs 13, 13 arranged between the side gears 29, 31 and the pressing members 7, 7 are
Interference with peripheral members such as 7, 29, 31 is prevented,
Wear and damage are avoided.

For these reasons, the disc springs 13, 1
In No. 3, a change in spring constant and a decrease in durability are prevented, and a normal initial torque can be obtained for a long period of time.

Further, since it is an internally pushed type, the biasing force of the disc springs 13 and 13 can be exerted even when the vehicle turns suddenly or is put in a garage.
Cam thrust force of the cams 9, 9 and side gears 29, 31
The fluctuation of the balance with the meshing reaction force of (1) and the fluctuation of the pressing force of the multi-plate clutches 11, 11 due to the fluctuation of the balance are reduced, and the tight corner braking phenomenon and the abnormal noise accompanying it are reduced.

The cams 9 and 9 allow the side gear 2 to move.
Since the disc springs 13 and 13 are arranged in the gaps formed between the 9 and 31 and the pressing members 7 and 7, and the existing space is effectively used, in order to provide the arrangement space for the disc springs 13 and 13, There is no need to change the internal structure or layout of the differential device 1, and it is possible to make the internal push type at low cost.

Further, as compared with the structure in which the disc spring 13 and the cam 9 are arranged in the radial direction so as to overlap with each other, the differential device 1 becomes axially more compact, and the vehicle mountability is improved. Has improved.

Further, since the disc springs 13 and 13 are small and lightweight, the differential device 1 is constructed so light and compact that the vehicle mountability is improved.

Further, since the disc springs 13 and 13 can obtain a large pressing force with a short free length, as described above, due to the large initial torque, the rough road running property, the starting property, the
Acceleration, maneuverability, stability, etc. can be sufficiently improved.

Further, the spline 3 of the casing body 19
Since 5 is shared between the engagement of the pinion shaft 25 and the engagement of the outer plate 49 of each multi-plate clutch 11, the assemblability of these is improved.

Further, the spline 35 penetrating the casing body 19 has good workability, and the work cost is reduced accordingly.

In the present invention, the biasing means is not limited to the disc spring, but may be another spring such as a coil spring or an elastic member.

If a coil spring is used, a change in load (spring force) with respect to stroke (deflection amount) is small, so that a stable initial torque can be obtained.

Further, the friction clutch is not limited to the multi-plate clutch, but may be another type of friction clutch such as a single-plate clutch or a conical clutch.

The differential mechanism is not limited to the bevel gear type differential mechanism, but may be, for example, a planetary gear type differential mechanism.
A differential mechanism in which a pair of output side gears are connected by a pinion gear slidably and rotatably housed in a housing hole of a differential case, a differential mechanism using a worm gear, and the like may be used.

Further, the differential device of the present invention is
Front differential (differential device that distributes engine drive power to the left and right front wheels) and rear differential (differential device that distributes engine drive power to the left and right rear wheels)
And a center differential (a differential device that distributes the driving force of the engine to the front wheels and the rear wheels).

[0088]

In the differential device of the present invention, the urging force of the urging means and the cam thrust force of the cam means and the meshing reaction force of the side gears are arranged in parallel, so that the cam thrust force of the cam means and the meshing reaction force of the side gears. Since the differential limiting force due to rises instantly, it is possible to sufficiently improve the startability, acceleration, maneuverability, stability and the like.

Further, unlike the conventional example, since the differential limiting force is not lost due to the deflection of the biasing means, when one wheel idles, the torque sent to the other wheel becomes large, and the starting property and acceleration are increased. The operability, maneuverability and stability are further improved.

Further, the biasing means is released from the repeated expansion and contraction due to the cam thrust force of the cam means and the meshing reaction force of the side gears, the spring constant is prevented from deteriorating, the initial torque is stabilized, and the durability of the biasing means is improved. Greatly improved.

The differential device according to the second aspect can obtain the same effect as that of the configuration according to the first aspect.

In addition to this, the urging means is arranged in the gap formed between the side gear and the pressing member by the cam means, and the existing space is effectively utilized to provide a space for arranging the urging means. Therefore, there is no need to change the internal structure or layout, and the differential device can be constructed at low cost.

Further, the urging means connected by the cam means and arranged between the side gear and the pressing member in which a large relative rotation does not occur is released from the abrasion due to the sliding, and the change of the spring constant and the deterioration of the durability are reduced. This prevents the desired initial torque from being obtained for a long period of time.

Further, by arranging the biasing means and the cam means so as to overlap each other in the radial direction, the differential device is made compact in the axial direction, and the vehicle mountability is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of one embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a graph showing a torque-sensitive differential limiting characteristic having an inward-pressing initial torque and a torque-sensitive differential limiting characteristic having an outward-pressing initial torque.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

1 differential device 3 differential case 5 Bevel gear type differential mechanism 7,7 pressing member 9,9 cam (cam means) 11,11 Multi-plate clutch (friction clutch) 13,13 Disc spring (biasing means) 29,31 Output side gear

Claims (2)

[Claims] 1. A differential case that rotates by receiving the driving force of a prime mover, a differential mechanism that distributes the rotation of the differential case to the outside from a pair of output side gears, a pressing member connected to the wheel side, and the differential case. A friction clutch for limiting a differential provided between the side gear and the pressing member, and a cam that is provided between the side gear and the pressing member, operates by receiving torque, and presses the friction clutch via the pressing member. And a biasing unit that is disposed between the side gear and the pressing member and presses the friction clutch via the pressing member to apply an initial torque. 2. The differential device according to claim 1, wherein the urging means is arranged in a gap formed by the cam means between a side gear and a pressing member. .