JP2001330060A - Coupling and differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely return cam members of a cam mechanism to the initial positions. SOLUTION: A coupling 1 is provided with a case-like torque transmitting member 3, a shaft-like torque transmitting member 9 inserted into the case-like torque transmitting member, a main clutch 11 arranged between both the torque transmitting members 3 and 9, a pilot clutch 19 to be intermittently operated by an operating means 51, and a cam mechanism 11 to be operated by the transmitting torque applied to both the torque transmitting members 3 and 9 when the pilot clutch 9 is connected so as to connect the main clutch 11 with the generated axial thrust force. Energizing means 14 and 16 for energizing cam members 15 and 17 in the rotating direction and the axial direction so as to return them to the initial positions are provided between the can members 15 and 17 of the cam mechanism 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coupling for transmitting power by a main clutch which is turned on and off by a cam which operates when a pilot clutch is connected, and a differential device for controlling a differential limiting force using the coupling. About.

[0002]

2. Description of the Related Art A conventional coupling and a differential device using this coupling are described in "Gaia New Model Manual, pp. 0-22 Toyota Motor Co., Ltd. Edited by the Service Department, May 29, 1998". FIG.
A coupling 201 such as 1 is described.

[0003] The coupling 201 is arranged in a rear wheel-side power transmission system of a four-wheel drive vehicle.
3, clutch hub 205, multi-plate main clutch 20
7, the pilot clutch 209, the armature 211,
Electromagnet 213, cam ring 215, ball cam 217,
It comprises a pressure plate 219, a controller and the like.

[0004] The coupling 201 includes a differential carrier 22.
1, and the core 223 of the electromagnet 213 is supported on the inner periphery of the differential carrier 221.

[0005] The rotating case 203 has a bearing 22 at the front.
5, and a rear portion thereof is supported by a differential carrier 221 by a core 223 and a bearing 227 of the electromagnet 213.

[0006] The rotary case 203 is connected from the transfer to the transmission via a propeller shaft. A drive pinion shaft 229 is spline-connected to the clutch hub 205, and a drive pinion gear 231 formed integrally therewith is connected to a ring gear on the side of a rear differential (a differential device for distributing the driving force of the engine to the left and right rear wheels). Are engaged.

The main clutch 207 includes a rotating case 203.
The pilot clutch 209 is disposed between the rotating case 203 and the cam ring 2.
15 are arranged.

The ball cam 217 is disposed between the cam ring 215 and the pressure plate 219, and the pressure plate 219 is spline-connected to the hub 205.

The controller excites the electromagnet 213, controls the excitation current, and stops the excitation. And the electromagnet 2
When the magnet 13 is excited, a magnetic loop 233 is formed in the magnetic circuit, the armature 211 is attracted, and the pilot clutch 209 is pressed and fastened. When the pilot clutch 209 is engaged, the torque between the rotating case 203 and the clutch hub 205 is applied to the ball cam 217,
Due to the generated cam thrust force, the pressure plate 21
9, the main clutch 207 is pressed and engaged.

When the coupling 201 is connected in this manner, the driving force of the engine is sent to the rear wheels, and the vehicle is driven in a four-wheel drive state, so that the running performance on rough roads and the stability of the vehicle body are improved.

When the exciting current of the electromagnet 213 is controlled, the cam thrust force of the ball cam 217 changes due to the slip of the pilot clutch 209, and the main clutch 2
The coupling force of 07 changes, and the driving force of the rear wheel is adjusted.

On the other hand, when the excitation of the electromagnet 213 is stopped,
The pilot clutch 209 is released and the ball cam 21 is released.
7, the main thrust force is released, the main clutch 207 is released, the connection of the coupling 201 is released, and the vehicle enters a two-wheel drive state.

[0013]

In such a structure, drag torque may be generated due to a change in running conditions, oil sealed in the coupling, or the like. In particular, the drag torque of the pilot clutch 209
Occurs, the cam ring 215, the ball cam 217,
Since the signal is amplified by the cam mechanism including the pressure plate 219, the influence on the main clutch 207 is increased.

For this reason, conventionally, as a countermeasure against this, a return spring that pushes back the pressure plate 219 against the drag torque is arranged.

However, since the return spring pushes back the pressing force amplified by the cam mechanism, a large spring force is required, and the spring is inevitably a large spring. Conversely, when the pilot clutch 209 is connected, a pressing force against the large pushing-back force of the return spring is required.
This is a contradiction that the cam mechanism needs to be enlarged. Therefore, the weight of the coupling 201 as a whole increases, and the coupling 201 becomes large, which affects the vehicle mountability and the peripheral design.

Further, when a drag torque is generated, the sliding portion between the return spring and the pressure plate 219, which is a rotating body, is prevented from being galled. It is necessary to arrange members. As a result, there is a problem that the number of parts increases and the structure becomes complicated.

Accordingly, the present invention provides a coupling having a structure capable of opposing a drag torque without providing a large return spring, enabling a reduction in weight and size, and a differential limiting system using this coupling. It is an object to provide a differential device for controlling a force.

[0018]

According to a first aspect of the present invention, there is provided a coupling comprising: a case-shaped torque transmitting member; a shaft-shaped torque transmitting member penetrating the case-shaped torque transmitting member;
When the main clutch disposed between the two torque transmitting members, the pilot clutch intermittently operated by the operating means, and the pilot clutch are connected, the main clutch operates by receiving the transmission torque applied to the two torque transmitting members. A cam mechanism for connecting the main clutch by an axial thrust force, wherein the cam member is rotationally and axially urged between the cam members of the cam mechanism to return to the initial position. It is characterized by the provision of force means.

When the pilot clutch is connected, the cam mechanism operates by the thrust force between the case-shaped torque transmitting member and the shaft-shaped torque transmitting member, and the main clutch is pressed and fastened.

In the present invention, since the urging means is provided between the cam members of the cam mechanism, even if a drag torque is generated, the cam member is initially rotated in the rotational and axial directions before the torque is amplified by the cam mechanism. To return to the position, the cam member can be returned with a small force. Therefore, there is no need to increase the size of the urging means and the cam mechanism in order to oppose the drag torque, so that the weight and the size can be reduced, and the vehicle mountability and the degree of freedom in peripheral design can be improved.

Further, since the urging means is arranged between the cam members, the urging means does not slide on the rotating member, and there is no fear of occurrence of galling. Therefore, no anti-galling member is required, and the structure can be simplified.

Furthermore, since the urging means urges in the rotational direction and the axial direction, the cam member can be reliably returned even if the drag torque acts in the torsional direction and the pulling direction, and the response is improved.

According to a second aspect of the present invention, in the first aspect of the present invention, the urging member is a coil spring.

By using a coil spring as the urging means, it is possible to urge in a rotational direction and an axial direction with a simple structure.

The invention according to claim 3 is the invention according to claim 1, wherein the biasing member is a torsion spring.

The twisting of the torsion spring accumulates the restoring torque in the rotational direction and the axial direction, so that the torsion spring can be urged in the rotational direction and the axial direction with a simple structure.

The invention according to claim 4 is the invention according to claim 1, characterized in that a coil spring and a torsion spring are provided as the urging member.

The coil spring is mainly biased in the axial direction,
Since the torsion spring urges in the rotation direction, the cam member can be reliably returned to the initial position.

The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the operating means is an electromagnet for moving the armature to press and connect the pilot clutch. It is characterized by:

By using an electromagnet as the operating means, the controllability is improved and more precise control is possible.

According to a sixth aspect of the present invention, there is provided a differential device comprising: a case-shaped torque transmitting member which is rotated by a driving force of an engine; and a pair of shaft-shaped torque transmitting members which rotate the case-shaped torque transmitting member. A differential mechanism that is distributed to the wheel side via a clutch, and a coupling that is arranged between the torque transmitting members, and limits a differential of the differential mechanism by a clutch disposed between the coupling and the coupling according to any one of claims 1 to 5. It is characterized by having.

According to the present invention, the coupling of the pilot clutch of the coupling causes the cam mechanism to operate by receiving the differential torque of the differential mechanism, and the main clutch is pressed and engaged by the converted cam thrust force, and its frictional resistance is reduced. Limits the differential.

With this differential limiting force, one-wheel idling is limited, and the starting and accelerating properties of the vehicle, the running ability on rough roads, the escape property, and the like are improved.

On the coupling side, when the operating means is adjusted to give an appropriate amount of slip to the pilot clutch, the cam thrust force of the cam mechanism changes, the coupling force of the main clutch changes, and the differential limiting force is adjusted. You.

Thus, when the differential limiting force is adjusted in such a manner during turning, the turning performance and the stability of the vehicle body during turning are greatly improved.

When the connection of the pilot clutch is released, the cam thrust force of the cam mechanism is lost, the main clutch is released, and the differential rotation of the differential mechanism becomes free.

In addition, in the differential device of the present invention, the biasing means is provided between the cam members of the cam mechanism, so that the cam member can be initialized even if a drag torque is generated due to a change in running conditions or the like. In order to surely return to the position, the restriction of the differential mechanism can be reliably performed.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described with reference to FIGS.

In the four-wheel drive vehicle, the coupling 1 of this embodiment is disposed between the rear differential and the engine (transfer) side on the disconnected side. Has features. The left side of FIG. 1 corresponds to the front (engine side) of the vehicle. In addition, members and the like without reference numerals are not shown.

The coupling 1 includes a clutch housing 3, a power transmission shaft 5, a clutch hub 9, and a main clutch 1.
1, cam mechanism 12, pilot clutch 19, electromagnet 5
1 and the like.

The coupling 1 is housed in a casing fixed to the vehicle body. The clutch housing 3 is
It constitutes a case-shaped torque transmission member, and is formed in a cylindrical shape having openings 21 and 23 in front and back,
It is made of non-magnetic aluminum or stainless steel. The power transmission shaft 5 is made of steel and has a flange 25 formed thereon. The flange 25 is fixed to the front opening 21 of the clutch housing 3 with bolts 27.

[0042] A companion flange (not shown) is serrated and connected to the power transmission shaft 5 and fixed with a nut. The companion flange is connected to the engine (transfer) side by being connected to the flange on the propeller shaft side.

The opening 23 on the rear side of the clutch housing 3
, A magnetic ring-shaped rotor 31 is attached and positioned by a retaining ring 33. The rotor 31 rotates integrally with the clutch housing 3 by engaging the protrusion 35 with the groove 37 of the clutch housing 3.

The power transmission shaft 5, the clutch housing 3 and the rotor 31 are integrated as described above, and these are formed by the bearing 39 on the power transmission shaft 5 and the bearing 41 on the rotor 31. It is supported by

The clutch hub 9 is connected to the clutch housing 3
The front end of the ball bearing 4
3 is supported on the flange portion 25 of the power transmission shaft 5,
The rear end is supported on the rotor 31 by a needle bearing 45.

The clutch hub 9 constitutes a shaft-shaped torque transmitting member, and is serrated and connected to a drive pinion shaft on the rear differential side.

The main clutch 11 is a multi-plate clutch, and is disposed between the clutch housing 3 and the clutch hub 9.

The cam mechanism 12 includes a ball cam 13, a pressure plate 15, and a cam ring 17. The ball cam 13 is arranged between the pressure plate 15 and the cam ring 17.

The pressure plate 15 is spline-connected to the clutch hub 9 so as to be movable in the axial direction.
Is pressed and fastened.

The cam ring 17 is arranged on the outer periphery of the clutch hub 9, and a thrust bearing 47 for receiving a cam reaction force of the ball cam 13 is arranged between the cam ring 17 and the rotor 31.

The thrust bearing 47 is arranged in the concave portion 48 provided between the cam ring 17 and the rotor 31 and the space for the thrust bearing 47 is reduced accordingly. There is no restriction on the space in the axial direction of the member.

As shown in FIG. 2, the pressure plate 15 and the cam ring 17 constituting the cam mechanism 12 are both formed in a ring shape and are opposed to each other.
A coil spring 14 and a torsion spring 16 are provided as urging means. Coil spring 1
4 and a torsion spring 16 are paired, and a ring-shaped pressure plate 15 and a cam ring 17 are formed.
Are provided at a plurality of places (three places) at equal intervals along the circumferential direction.

The coil spring 14 and the torsion spring 16 are provided with mounting recesses 18, which are formed at circumferentially opposed portions of the pressure plate 15 and the cam ring 17.
20, it is arranged between the pressure plate 15 and the cam ring 17.

The mounting recess 18 in which the coil spring 14 is mounted has a T-shaped slit. When both ends of the coil spring 14 are inserted, both ends of the coil spring 14 are engaged and the pressure plate 15 And the cam ring 17. Accordingly, the pressure plate 15 and the cam ring 17 are mainly urged in the axial direction as shown by the arrow T1 in FIG. 3, and act to return the pressure plate 15 and the cam ring 17 to the initial position in the axial direction.

On the other hand, the mounting recess 20 in which the torsion spring 16 is mounted has a linear slit, and the pressure plate 15 and the cam ring 17 are inserted by inserting the torsion spring 16 into the slit mounting recess 20. Placed between. Therefore, the pressure plate 15 and the cam ring 17 mainly rotate in the rotational direction (twist direction) as shown by the arrow T2 in FIG.
And acts to return the pressure plate 15 and the cam ring 17 to their initial positions in the rotation direction.

Since the coil spring 14 and the torsion spring 16 are provided between the pressure plate 15 and the cam ring 17, even if a drag torque is generated, the pressure is maintained before the drag torque is amplified by the cam mechanism. Since the plate 15 and the cam ring 17 are returned to the initial positions in the rotation direction and the axial direction, the pressure plate 15 and the cam ring 17 can be returned with a small force.

Note that the pressure plate 15 is integrally fixed with the ring 22 fixed thereto. A spline portion 24 is provided on the inner periphery of the ring 22, and the spline portion 2
4 is spline-connected to the outer periphery of the clutch hub 9.

The pressure plate 15 and the ring 22 having the spline portion 24 are separately processed and then fixed. Therefore, since the ring 22 can machine the spline portion 24 by itself and can be heat-treated, the machining is easy, and the heat treatment that can be performed without affecting the pressure plate 15 is also easy. Therefore, the processing cost can be reduced accordingly.

The pilot clutch 19 comprises a multi-plate clutch, and is disposed between the clutch housing 3 and the cam ring 17. The pilot clutch 19 is intermittently operated by an electromagnet 51 as operation means. As described above, since the thrust bearing 47 does not restrict the peripheral members in terms of space, the multiple disc clutch 19
Has sufficient capacity given the required number of clutch plates.

The electromagnet 51 is fixed to the casing on the vehicle body side, and its yoke 55 penetrates into the concave portion 57 of the rotor 31 through an appropriate gap. This yoke 55
, The rotor 31 is supported via a seal bearing 59.

The electromagnet 51 is connected to the battery via a lead wire 54, and the operation of exciting and stopping the excitation is performed by a controller.

The armature 53 is the pilot clutch 19
Is disposed adjacent to the front side of. The rotor 31, the pilot clutch 19 and the armature 53 form a magnetic circuit 61 of the electromagnetic solenoid 51.

A non-magnetic stainless steel ring 63 is disposed on the rotor 31 to prevent the magnetic circuit 61 from bypassing the magnetic force. A notch 65 is provided in the pilot clutch 19 at a position corresponding to the ring 63 to prevent the magnetic force of the magnetic circuit 61 from being bypassed.

When the electromagnet 51 is excited, the armature 53 is attracted through the magnetic circuit 61 and presses and engages the pilot clutch 19 to generate pilot torque.

When a pilot torque is generated in the pilot clutch 19, the ball cam 1 is transmitted from the clutch housing 3 via the pilot clutch 19 and the cam ring 17.
The driving force of the engine is applied to the main clutch 3 and the main clutch 11 through the pressure plate 15 by the thrust force.
Are pressed and fastened, and the coupling 1 is connected.

When the coupling 1 is connected, the rear differential is connected to the engine side, and the vehicle enters a four-wheel drive state.

At this time, the controller controls the electromagnet 5
By controlling the strength of the magnetic force of No. 1, the pilot torque of the pilot clutch 19 changes due to the slip, and the thrust force of the ball cam 13 changes, so that the coupling force between the main clutch 11 and the coupling 1 can be adjusted.

As described above, by adjusting the coupling force of the coupling 1, the torque distribution ratio between the front wheels and the rear wheels of the vehicle can be arbitrarily adjusted.

When the excitation of the electromagnet 51 is stopped, the pilot torque of the pilot clutch 19 is lost, the main clutch 11 is released, and the connection of the coupling 1 is released.

When the connection of the coupling 1 is released, the rear differential is disconnected, and the vehicle enters a front-wheel drive two-wheel drive state.

The clutch housing 3 is made of a non-magnetic material, and when the electromagnet 51 is excited, the magnetic force is prevented from leaking to other members via the clutch housing 3. Is efficiently guided to the motor, and a predetermined pilot torque by the pilot clutch 19 is obtained.

Also, as described above, the power transmission shaft 5, the clutch housing 3, and the rotor 3 forming an integral container
The oil is injected into the inside of 1 through an oil hole 67 provided in the flange portion 25 of the power transmission shaft 5. After oil injection, the oil hole 67 is sealed by a ball 69.

An O-ring 71 is disposed between the flange 25 of the power transmission shaft 5 and the clutch housing 3, and an O-ring 73 is disposed between the clutch housing 3 and the rotor 31. An X ring 75 is arranged between the clutch hub 9 and the clutch hub 9 to prevent oil leakage to the outside.

The oil thus sealed is held in an oil sump 77 provided on the clutch hub 9. Also,
The clutch hub 9 is provided with a radial oil passage 79 communicating with the oil sump 77.

When the clutch hub 9 rotates, the oil passes from the oil sump 77 to each of the oil passages 79 and is provided to the main clutch 11 and the ball bearings 43 to lubricate them. Further, the ball cam 13, the thrust bearing 47, and the pilot Lubricate the clutch 19, the X ring 75 and the like.

Thus, the coupling 1 is configured.

As described above, the pressure plate 15
A coil spring 14 and a torsion spring 16 are arranged between the cam ring 17 and the cam ring 17 to urge the pressure plate 15 and the cam ring 17 to return to their initial positions in the rotation direction and the axial direction.

As described above, by disposing the coil spring 14 and the torsion spring 16 for urging the pressure plate 15 and the cam ring 17 to return to the initial positions in the rotation direction and the axial direction, a drag torque is generated. However, before the drag torque is amplified by the cam mechanism, the pressure plate 15 and the cam ring 17 are returned to the initial positions in the rotational and axial directions. Therefore, the pressure plate 15 and the cam ring 17 can be returned with a small force.

Since the pressure plate 15 and the cam ring 17 can be returned with a small force as described above, it is not necessary to increase the size of the coil spring 14 and the torsion spring 16.

Further, since the coil spring 14 and the torsion spring 16 act with a small force, a large pressing force is not required for connecting the pilot clutch 19, and the pressure plate 15 and the cam ring 17 do not need to be large.

As described above, since it is not necessary to increase the size of the urging means including the coil spring 14 and the torsion spring 16 and the cam member including the pressure plate 15 and the cam ring 17, the weight of the entire coupling 1 can be reduced. In addition, the size can be reduced and the degree of freedom in vehicle mounting and peripheral design can be increased.

Further, since the coil spring 14 and the torsion spring 16 are arranged between the pressure plate 15 and the cam ring 17, there is no sliding and there is no fear of occurrence of galling. Therefore, no anti-galling member is required, and the structure can be simplified.

Further, since the coil spring 14 and the torsion spring 16 are urged in the rotation direction and the axial direction, the pressure plate 15 and the cam ring 17 can be securely returned even if the drag torque acts in the torsion direction and the pulling direction. , The response is improved.

In this embodiment, the pilot clutch 1
9 is used by using an electromagnet 51. Electromagnet 5
1 can easily control the strength of the magnetic force, and therefore, the coupling of the coupling 1 can be controlled as described above. Therefore, controllability is improved.

In addition, the clutch housing 3 is made of a non-magnetic material corresponding to the electromagnet 51. This allows
The magnetic force of the electromagnet 51 is prevented from leaking from the clutch housing 3 to other members, the loss of exciting power is greatly reduced, the load on the battery is reduced, and the fuel efficiency of the engine is improved. Also, since the leakage of magnetism is prevented, the electromagnet 5
1. Since the pilot clutch 19, the ball cam 13 and the like can be reduced in size, and the main clutch 11 can also be reduced in size, the coupling 1 can be made lighter and more compact.

FIGS. 4 to 6 show different embodiments of the urging member of this embodiment. In this embodiment, a C-shaped torsion spring 26 is used as an urging means for returning the pressure plate 15 and the cam ring 17 to the initial position.
Is used. The torsion spring 26 has hook portions 28 and 29 at both ends in the length direction. One of the hook portions 28 is inserted into the hook slit 30 of the pressure plate 15, and the other hook portion 29 is connected to the cam ring 17.
Is inserted between the pressure plate 15 and the cam ring 17.

Such a C-shaped torsion spring 2
6, the pressure plate 15 and the cam ring 17
In the rotational direction (twist direction) as shown by the arrow T2 in FIG.
And acts to return the pressure plate 15 and the cam ring 17 to their initial positions in the rotation direction.
As shown by an arrow T1 in FIG. 6, the pressure plate 15 and the cam ring 17 are urged in the axial direction.
It works to return the pressure plate 15 and the cam ring 17 to the initial position in the axial direction.

Therefore, even if a drag torque is generated, the pressure plate 15 and the cam ring 17 are returned to their initial positions in the rotational and axial directions before the drag torque is amplified by the cam mechanism. The cam ring 17 can be returned.
Further, since the rotation direction and the axial direction are returned only by a single torsion spring, the urging means can have a simple structure, and the size and weight can be reduced.

Note that, instead of the torsion spring, only the coil spring may be used as the urging means. In this case, the torsion spring 16 of FIGS. 2 and 3 may be omitted, and a plurality of coil springs 14 may be arranged in the circumferential direction. The coil spring 14 is wound with a large diameter as shown in FIGS. A coil spring alone may be used. Even in such a coil spring, it is possible to urge not only in the axial direction but also in the rotational direction.

(Second Embodiment) FIG. 7 shows a differential device (rear differential) 80 according to a second embodiment of the present invention. In this embodiment, members having the same functions as in the first embodiment are given the same reference numerals.

The rear differential 80 has the features of the first to sixth aspects. The rear differential 80 distributes the driving force of the engine to the left and right rear wheels, and is arranged on the rear axle of the rear wheel drive vehicle. This power system includes an engine, a transmission, a propeller shaft, a rear differential 80, left and right rear axles, left and right rear wheels, and the like.

[0092] The rear differential 80 is disposed inside the differential carrier, and the differential carrier is provided with an oil reservoir.

The rear differential 80 comprises a differential case 81, a bevel gear type differential mechanism 90, the electromagnetic coupling 1 of the first embodiment, a controller and the like.

The coupling 1 is composed of a multi-plate type main clutch 11, a pilot clutch 19, a cam mechanism 12, an intermediate pressing member 95, an armature 53, an electromagnet 51, and the like.

The bosses 82 and 83 formed at both ends in the axial direction of the differential case 81 are supported on the differential carrier by angular contact bearings.

A ring gear is fixed to the differential case 81, and this ring gear meshes with a drive pinion gear. The drive pinion gear is formed on a drive pinion shaft, and the drive pinion shaft is connected to the propeller shaft side.

Thus, the driving force of the engine is transmitted from the transmission to the differential case 81 via the propeller shaft.
Is driven to rotate.

The differential mechanism 90 includes a plurality of pinion shafts 94, the same number of pinion gears (input gears) 91,
It is composed of left and right side gears (output gears) 92, 93 and the like.

Each of the pinion shafts 94 is arranged radially, and the inner end of each of the pinion shafts 94 is connected to the thrust block 38.
Are connected to each other, and the outer end is a differential case 81.
And is fixed by a spring pin 102.

The pinion gear 91 has a pinion shaft 94.
The side gears 92 and 93 are in mesh with the respective pinion gears 91 from the left and right. A spherical washer 103 is arranged between each pinion gear 91 and the differential case 81, and the centrifugal force of the pinion gear 91 and the side gear 9
2 and 93 due to a meshing reaction force generated by meshing with the input shaft 2 (upper part in the drawing).

The left and right rear axles are respectively provided with bosses 82, 8
3 penetrates into the differential case 81, and the side gears 92, 93
Is splined.

The driving force of the engine for rotating the differential case 81 is distributed from the pinion shaft 94, the pinion gear 91, and the side gears 92 and 93 to the rear axle and transmitted to the left and right rear wheels.

If a difference in driving resistance occurs between the rear wheels on a rough road, the driving force of the engine is rotated by the rotation of the pinion gear 91 when the differential limiting mechanism of the coupling 1 is released as described below. Are differentially distributed to the left and right rear wheels.

The main clutch 11 of the coupling 1
It is arranged between the outer periphery of the boss 104 formed on the left side gear 92 and the inner periphery of the differential case 81. A spacer 105 is attached to the outer periphery of the boss 104, and the main clutch 1 is connected via the spacer 105.
1 is arranged.

The cam force of the left side gear 92 generated by the engagement with the pinion gear 91 is
The input is made to the main clutch 9 via the.

The cam force referred to here means a pinion gear 91 as an input gear and side gears 92 and 93 as output gears.
Is a component force in the thrust direction caused by the engagement between That is, the engagement pressure angle becomes the cam angle in the bevel gear, and an extremely large cam force can be obtained.

On the other hand, the cam force of the right side gear 93 is input to the differential case 81 via the thrust washer 106 and received.

A stainless steel (non-magnetic material) ring 107 is welded to the right end of the differential case 81, and a magnetic material rotor 31 integrated with the right boss 83 is welded to this ring 107. I have.

The pilot clutch 19 is
07 and the cam ring 17 of the cam mechanism 12.

The cam mechanism 12 includes a ball cam 13, a cam ring 17, and a pressure plate 15.

The ball cam 13 is disposed between the cam ring 17 and the pressure plate 15. Between the cam ring 17 and the rotor 31, a thrust bearing 108 receiving the cam reaction force of the ball cam 13 and the washer 1 are provided.
09 is arranged.

The pressure plate 15 has a boss 110 welded to the right side gear 93 and a spline 11
1 so as to be movable.

A recess 6 is formed in a portion of the cam mechanism 12 facing the cam ring 17 and the pressure plate 15. The concave portions 6 are formed at a plurality of locations along these circumferential directions, and a coil spring 7 as an urging means is inserted into each of the concave portions 6. Coil spring 7 includes cam ring 17 and pressure plate 1
5, the pressure plate 15 and the cam ring 17 are urged in the axial direction and the rotation direction.
7 to return to the initial position in the axial and rotational directions.

As described above, since the coil spring 7 is provided between the pressure plate 15 and the cam ring 17, even if the drag torque is generated, the pressure plate 15 and the cam plate 17 are not amplified before the drag torque is amplified by the cam mechanism. Since the cam ring 17 is returned to the initial position in the rotation direction and the axial direction, the pressure plate 15 and the cam ring 17 can be returned with a small force.

The intermediate pressing member 95 is connected to the main clutch 11
Ring 96 and thrust washer 9
The ring 98 includes a ring 98 facing the pressure plate 15 through the arm 7 and an arm member 99 that connects the rings 96 and 98 between the pinion shafts 91. The intermediate pressing member 95 is formed by a ring
13 is connected to the inner periphery of the differential case 81 movably in the axial direction, and transmits the pressing force of the pressure plate 15 to the main clutch 11.

By using the intermediate pressing member 95, the main clutch 11 can be connected to the other pilot clutch 19, the ball cam 13, the cam ring 17, the pressure plate 15, the armature 5,
3. It can be arranged on the opposite side of the differential mechanism 90 in the axial direction with respect to the electromagnet 51 and the like.

Also, by arranging the components of the coupling 1 on both sides in the axial direction of the differential mechanism 90, the weight and the dimensional balance are adjusted in the axial direction.

The armature 53 includes the pilot clutch 1
9 and a pressure plate 15 so as to be movable in the axial direction.

The yoke 55 of the electromagnet 51 is supported on the boss portion 83 of the differential case 81 by a ball bearing 114, is connected to the differential carrier via a connecting member 115, and is prevented from rotating.

The boss portion 83 is formed integrally with the rotor 31, and the rotor 31 forms a part of the magnetic circuit 61 of the electromagnet 51. The ring 107 prevents the magnetic flux from leaking to the left side of the differential case 81 and concentrates the magnetic flux on the armature 53.

An air gap is formed between the yoke 55 and the rotor 31. The rotor 31 is radially divided by a stainless steel ring 63, and notches are provided at equal intervals in the circumferential direction on each clutch plate of the pilot clutch 19. The ring 63 and the notch prevent a short circuit of magnetic force in the magnetic circuit 61.

The controller detects turning based on the vehicle speed, steering angle, lateral G, etc., or controls the excitation of the electromagnet 51 and the excitation current in accordance with the road surface condition, starting, acceleration, and the like.
The excitation is stopped, and the differential limiting force of the coupling 1 (between the rear wheels) is adjusted.

When the electromagnet 51 is excited, a magnetic loop 61 is formed, the armature 53 is attracted to the right, and the pilot clutch 19 is pressed to be engaged.

When the pilot clutch 19 is engaged,
A differential torque is applied to the ball cam 13 via the cam ring 17 connected to the differential case 81 by the pilot clutch 19 and the pressure plate 15 on the side gear 93 side, and the pressure plate 15 moves leftward by receiving the generated cam thrust force. , Thrust washer 9
The main clutch 11 is pressed and engaged via the 7 and the intermediate pressing member 95.

When the main clutch 9 is engaged, the differential rotation of the differential mechanism 90 is limited by the frictional resistance, and the differential rotation (idling) between the rear wheels is limited by the differential limiting force, so that the vehicle is not driven. Driving on rough roads, startability, acceleration, stability, etc. are greatly improved.

When the excitation of the electromagnet 51 is stopped, the pilot clutch 19 is released, the cam thrust force of the ball cam 13 disappears, the main clutch 11 is released, and the differential rotation becomes free.

Openings 116 and 117 are provided in the differential case 81, and spiral oil grooves 118 and 119 are provided in the inner periphery of the bosses 82 and 83.

The openings 116 and 117 and the oil grooves 1 are provided in the differential case 81 from the oil reservoir of the differential carrier.
The oil flows in and out through the gears 18 and 119, and the inflowing oil flows through the meshing portions of the gears of the differential mechanism 90, the main clutch 1, the pilot clutch 19, the ball cam 13, the spherical washer 103, the thrust bearing 108, the washer 109, Spline part 111, thrust washer 97
To lubricate and cool them.

The opening 117 of the ring 107 is provided at a position facing the pilot clutch 19 and the armature 53, and the centrifugal oil is discharged from these openings 117 so that the pilot clutch 19 and the armature 53 are separated. The oil flow through the engine 53 is promoted, the lubrication and cooling effects of the pilot clutch 19 are enhanced, the movement of the armature 53 is smoothed, and the connection and disconnection of the pilot clutch 19 (rise and fall of the differential limiting force). To promote.

In addition, the pressure plate 15
A plurality of coil springs 7 for returning these to the initial position are provided in the circumferential direction between the cam ring 17 and the cam ring 17. Thus, even if the drag torque is generated, the pressure plate 15 and the cam ring 17 can be returned to the initial positions in the rotational and axial directions with a small force before the drag torque is amplified by the cam mechanism. Therefore, it is not necessary to increase the size of the coil spring 7, the pressure plate 15, and the cam ring 17, and the weight and the size can be reduced. In addition, since the coil spring has a simple structure, it can be easily assembled.

Further, urging means (coil spring 7)
When the differential limit is released, the differential position can be reliably and quickly returned to the initial position reliably and quickly even when the differential control is frequently turned on and off, such as during slalom turning. Therefore, traveling performance and traveling stability can be remarkably improved.

Note that also in this embodiment, the first
As in the embodiment, a coil spring and a torsion spring may be used as a pair as biasing means, or only a torsion spring may be used, or only a coil spring wound with a large diameter may be used. is there.

(Third Embodiment) A differential device (rear differential) 120 according to a third embodiment of the present invention will be described with reference to FIGS. In this embodiment, members having the same functions as those in the first embodiment and the second embodiment are given the same reference numerals. The rear differential 120 has the features of claims 1 to 5.

The rear differential 120 has a differential case 81,
Rotating case 121, bevel gear type differential mechanism 90, first
The coupling 1 according to the embodiment is provided.

The rotary case 121 is disposed on the inner periphery of the differential case 81 so as to be relatively rotatable.

The differential mechanism 90 includes a plurality of pinion shafts 94 fixed to the rotating case 121, pinion gears 91 supported on the respective pinion shafts 94, output side gears 92 meshed with these pinion gears 91,
93. Each side gear 92, 93
It is splined to the left and right rear axles.

The coupling 1 acts as an on / off clutch for connecting / disconnecting the differential case 81 and the rotating case 121 as described below.

When a drive source (not shown) is rotated in a state where the coupling 1 is connected, the differential case 81 is rotationally driven via a speed reduction mechanism.
The coupling 1, the pinion shaft 94, and the pinion gear 91 are distributed to the left and right rear wheels via the side gears 92 and 93 and the rear axle, and the vehicle is driven.

When a difference in driving resistance occurs between the rear wheels on a bad road or the like, the driving force is differentially distributed to the left and right rear wheels by the rotation of the pinion gear 91.

The coupling 1 includes an intermediate clutch 12
3, pilot clutch 19, ball cam 13, cam ring 17, pressure plate 15, armature 5
3, an electromagnet 51, a controller and the like.

The intermediate clutch 123 has a cylindrical shape and is arranged between the main clutch 11 and the pressure plate 15 of the cam mechanism 12. The intermediate clutch 123 transmits the pressing force of the pressure plate 15 to the main clutch 11.

The pilot clutch 19 is arranged between the rotor 31 and the cam ring 17. The pressure plate 15 is movably connected to the right side gear 93 by a spline portion provided between each other.

A return spring 126 composed of a coil spring is disposed between the differential case 81 and the main clutch 11. The return spring 126 is disposed between the cylindrical support plate 127 attached to the inner peripheral side of the main clutch 11 and the differential case 81, and urges the main clutch 11 to release the engagement.

The controller excites the electromagnet 51, controls the excitation current, and stops the excitation.

When the electromagnet 51 is excited, the armature 53
Presses and engages the pilot clutch 19, and applies the differential torque (driving force) of the differential mechanism 90 to the ball cam 13 via the cam ring 17 connected to the differential case 81 by the pilot clutch 19 and the pressure plate 15 on the side gear 93 side. ) Is applied, and the pressure plate 15 moves leftward due to the generated cam thrust force,
The intermediate clutch 123 is pressed, and the main clutch 11 is engaged.

When main clutch 11 is engaged, the driving force is transmitted to rear differential 120, and the vehicle is driven.

At this time, when the exciting current of the electromagnet 51 is controlled, the pilot clutch 19 slips, the cam thrust force of the ball cam 13 changes, and the main clutch 11
, The driving force transmitted to the wheel side is controlled.

When the excitation of the electromagnet 51 is stopped, the pilot clutch 19 is released, the cam thrust force of the ball cam 13 disappears, and the connection of the main clutch 11 is released.

In operation, oil is lubricated in the differential case to perform cooling and warming.

As shown in FIGS. 8 and 9, the cam mechanism 12
A coil spring 8 is disposed between the pressure plate 15 and the cam ring 17 as urging means. The coil spring 8 is mounted on the pressure plate 1
5 and wound around a large diameter in contact with the outer peripheral portion of the cam ring 17, and is provided between the pressure plate 15 and the cam ring 17 in a single state.

The large-diameter coil spring 8 is
The coil spring 8 is provided between the pressure plate 15 and the cam ring 17 as shown by an arrow T1 in FIG.
And the pressure plate 15 and the cam ring 17 in the rotational direction as shown by the arrow T2. Therefore, it acts to return the pressure plate 15 and the cam ring 17 to the initial positions in the axial direction and the rotational direction.

As described above, since the coil spring 8 is provided between the pressure plate 15 and the cam ring 17, even when the drag torque is generated, the pressure plate 15 and the cam plate 17 are not amplified before the drag torque is amplified by the cam mechanism. Since the cam ring 17 is returned to the initial position in the rotation direction and the axial direction, the pressure plate 15 and the cam ring 17 can be returned with a small force. Therefore, the coil spring 7 and the pressure plate 15
In addition, it is not necessary to make the cam ring 17 large, so that the weight and the size can be reduced, and the vehicle mountability and the degree of freedom in peripheral design can be improved.

Further, since the coil spring has a simple structure, the coil spring can be easily assembled.

In this embodiment, a coil spring and a torsion spring may be used as a pair of urging means, or only a torsion spring may be used.

In the present invention, the means for intermittently operating the pilot clutch 19 may be performed by pressing with hydraulic pressure or pneumatic pressure, or may be performed by a motor.

[0156]

According to the first aspect of the present invention, the urging means is provided between the cam members of the cam mechanism. Therefore, even if a drag torque is generated, the cam member is moved before the torque is amplified by the cam mechanism. The cam member can be returned with a small force to return to the initial position in the rotation direction and the axial direction, and there is no need to increase the urging means and the cam mechanism in order to oppose the drag torque. Can be.

Further, since the biasing means is arranged between the cam members, there is no sliding and there is no fear of occurrence of galling. Therefore, no anti-galling member is required, and the structure can be simplified.

Further, since the urging means urges in the rotational direction and the axial direction, the cam member can be reliably returned even if the drag torque acts in the torsional direction and the pulling direction, and the response is improved.

According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained, and the structure of the urging means can be simplified.

According to the third aspect of the invention, the same effect as that of the first aspect of the invention can be obtained, and the structure of the urging means can be simplified.

According to the fourth aspect of the invention, the same effect as that of the first aspect of the invention can be obtained, the structure of the urging means can be simplified, and the cam member can be reliably returned to the initial position. it can.

According to the fifth aspect of the invention, the same effects as those of the first to fourth aspects of the invention can be obtained, the controllability is improved, and fine control can be performed.

According to the sixth aspect of the invention, idling of one wheel is restricted, and the starting and accelerating properties of the vehicle, the running and escaping properties on rough roads, etc. are improved, and the turning performance and the vehicle body during turning are improved. Stability is greatly improved. In addition, even if a drag torque is generated due to a change in running conditions or the like, the cam member is reliably returned to the initial position, so that the differential mechanism can be reliably limited.

Further, when the differential restriction is released by the urging means, the initial position is reliably and promptly returned to the initial position. And can quickly limit and release the differential,
Drivability and running stability can be remarkably improved.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view showing a state where the urging means of the embodiment is arranged.

FIG. 3 is a cross-sectional view illustrating the operation of the urging means of FIG.

FIG. 4 is a perspective view showing the arrangement of different urging means.

FIG. 5 is a plan view showing a state where the urging means of FIG. 4 is arranged.

FIG. 6 is a sectional view for explaining the operation of the urging means of FIG.

FIG. 7 is a sectional view of a second embodiment of the present invention.

FIG. 8 is a sectional view of a third embodiment of the present invention.

FIG. 9 is a sectional view showing an arrangement of the urging means of the embodiment.

FIG. 10 is a side view for explaining the operation of the urging means of FIG. 9;

FIG. 11 is a sectional view of a conventional coupling.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coupling 3 Clutch housing 7 8 14 Coil spring 9 Clutch hub 11 Main clutch 12 Cam mechanism 13 Ball cam 16 Torsion spring 17 Cam ring 26 C type torsion spring 51 Electromagnet

Claims (6)

[Claims] 1. A case-like torque transmitting member, comprising:
When the shaft-shaped torque transmitting member penetrating into the gear-shaped torque transmitting member, the main clutch disposed between the two torque transmitting members, the pilot clutch intermittently operated by the operating means, and the pilot clutch are connected. A cam mechanism that operates by receiving the transmission torque applied to both torque transmission members and connects the main clutch by the generated axial thrust force, wherein the cam is disposed between the cam members of the cam mechanism. A coupling provided with a biasing means for biasing a member in a rotational direction and an axial direction and returning the member to an initial position. 2. The coupling according to claim 1, wherein said biasing member is a coil spring. 3. The coupling according to claim 1, wherein the biasing member is a torsion spring. 4. The coupling according to claim 1, wherein a coil spring and a torsion spring are provided as the urging member. 5. The invention according to claim 1, wherein the operating means is an electromagnet for moving the armature to press and connect the pilot clutch. Coupling. 6. A case which is rotated by a driving force of an engine.
A torque transmitting member, a differential mechanism for distributing rotation of the case-shaped torque transmitting member to the wheels via a pair of shaft-shaped torque transmitting members, and a torque transmitting member. A differential device comprising: the coupling according to claim 1, wherein a differential of the differential mechanism is limited by a clutch.