JPH10281184A - Drive force transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive force transmission device capable increasing the engaging force of a clutch as much as possible. SOLUTION: This drive force transmission device comprises a coupling case 1 and a shaft 6, relatively rotatably arranged; a main clutch 12 to control transmission of torque between the coupling case 1 and the shaft 6; a cam mechanism switched into an operation state to output a press force to engage the clutch 12 or a non-operation state to release a press force; an electromagnet 20 to mutually shift a cam mechanism intro an operation state or a non-operation state; and a pilot clutch 29. A differently constituted first cam mechanism 30 and a second cam mechanism 31 are provided, and the first and second cam mechanisms 30 and 31 are arranged in juxtaposition on inner and outer peripheries in a radial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force transmission device applied to a vehicle transmission, transfer, differential, and the like.

[0002]

2. Description of the Related Art Generally, a plurality of rotating members are arranged in a driving force transmitting device of a vehicle, and the output of an engine is transmitted to wheels via the plurality of rotating members. Further, in the driving force transmission device, when a clutch is arranged between a plurality of rotating members, the transmission or cutoff of torque can be arbitrarily switched by engaging and disengaging the clutch as necessary. Is possible.

An example of such a driving force transmitting device is described in Japanese Patent Application Laid-Open No. 3-282019. The driving force transmitting device described in this publication includes a carrier formed in a hollow, a connecting shaft (first rotating member) inserted into the carrier, a carrier disposed inside the carrier, and a position relative to the connecting shaft. A rotatable hub (second rotating member). The connection shaft and the hub are arranged on the axis, and a bearing is mounted between the carrier and the connection shaft.

Further, an annular electromagnet (switching mechanism) is attached to the carrier, and the electromagnet and the carrier are prevented from rotating by bolts. Further, a cylindrical side wall is fixed to the connection shaft, and a predetermined air gap is set between the side wall and the electromagnet. Further, a drum is connected to the outer periphery of the side wall, and a main clutch and a pilot clutch (switching mechanism) are provided between the drum and the hub.
And are arranged.

The pilot clutch includes a plurality of clutch discs spline-fitted on the inner circumference of the drum, a cam member mounted on the outer circumference of the hub so as to be movable in the axial direction, and a spline fit on the outer circumference of the cam member. It is composed of a plurality of clutch plates and an armature (switching mechanism) that is attracted to the side wall by electromagnetic force.

The main clutch includes a plurality of clutch disks spline-fitted to the inner periphery of the drum and a plurality of clutch plates spline-fitted to the flange of the hub. Further, an annular pressing member movable in the axial direction is disposed between the cam member and the main clutch. Furthermore, grooves are separately formed on the opposing surfaces of the cam member (cam mechanism) and the pressing member (cam mechanism), and each groove has an inclined surface. A ball (cam mechanism) is inserted between the grooves.

[0007] According to the driving force transmission device having the above-described structure, when no current is supplied to the electromagnet, the pilot clutch is released, and the torque of the connecting shaft is not transmitted to the hub.
When current is supplied to the electromagnet, magnetic flux passes through the side wall and the armature, and the armature is attracted to the side wall by the electromagnetic force. Then, the pilot clutch is engaged, the cam member is rotated, the cam member and the pressing member are relatively rotated by a predetermined angle, the ball is pressed against the inclined surface of the groove, the pressing member operates in the axial direction, and the main clutch is moved. Engaged. As a result, the torque of the connecting shaft is transmitted to the hub via the main clutch.

Here, since the cam member and the ball are arranged on the inner peripheral side of the pilot clutch, the engaging force (torque) of the pilot clutch is transmitted to the cam member in accordance with the radius difference, and the axis of the pressing member is increased. The pressing force in the direction is increased as much as possible. As a result, the engagement force of the main clutch is increased, and the function of transmitting torque is improved.

[0009]

However, in the driving force transmitting device described in the above publication, there is a possibility that the engaging force (torque capacity) of the main clutch becomes insufficient depending on the running state of the vehicle.

[0010] The present invention has been made in view of the above circumstances, and has as its object to provide a driving force transmission device capable of increasing the torque capacity of a clutch as much as possible.

[0011]

In order to achieve the above object, the invention of claim 1 comprises a first rotating member and a second rotating member which are arranged to be relatively rotatable, and wherein the first rotating member and the A clutch for controlling transmission of torque to and from the second rotating member, a cam mechanism capable of switching to an operating state for outputting a pressing force for engaging the clutch or a non-operating state for releasing the pressing force; In a driving force transmission device including a switching mechanism for switching a mechanism between an operating state and a non-operating state, a plurality of the cam mechanisms are arranged, and the cam mechanisms are arranged in parallel.

According to the first aspect of the present invention, the plurality of cam mechanisms arranged in parallel are switched between the operating state and the non-operating state by the switching mechanism. When the plurality of cam mechanisms are controlled to be in the non-operating state, the pressing force of the plurality of cam mechanisms is released and the clutch is released, so that the transmission of torque between the first rotating member and the second rotating member is prevented. Not done.

On the other hand, when the plurality of cam mechanisms are controlled to operate, the pressing forces are separately output from the plurality of cam mechanisms, and the clutches are engaged by the pressing forces. As a result, the engaging force of the clutch, that is, the torque capacity is increased as much as possible, and the function of transmitting the torque transmitted from the first rotating member to the second rotating member via the clutch is improved.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, each of the cam mechanisms is arranged in parallel on the inner and outer circumferences in the radial direction.

According to the second aspect of the invention, in addition to the same effect as the first aspect, the pressing force of each cam mechanism is dispersed in the radial direction, and the engaging pressure in the radial direction of the clutch becomes substantially equal. And stable torque transmission characteristics can be obtained.

As the plurality of cam mechanisms described in claim 1 or claim 2, the case where each cam mechanism is independently constituted by separate parts and the case where some of the parts of each cam mechanism are shared And are integrally configured.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a driving force transmitting device according to the present invention will be described in detail with reference to the accompanying drawings. The driving force transmission device is applied to a transmission, a transfer, a differential, and the like of a vehicle. In this embodiment, a description will be given based on a case where the driving force transmission device is applied to a torque transmission path between a propeller shaft and a differential.

FIG. 1 is a front half sectional view showing an embodiment of a driving force transmitting device. In FIG. 1, a coupling case 1 includes a cylindrical portion 2 rotatably arranged about an axis A, and an annular cover 3 fixed to one end of the cylindrical portion 2. A plurality of internal teeth 4 are formed on the inner circumference of the cylindrical portion 2 in the circumferential direction. The cover 3 has a substantially L-shaped cross section in the direction of the axis A, and a pressure receiving portion 5 is formed on the inner end surface of the cover 3 so as to protrude on the same circumference around the axis A. The cover 3 of the coupling case 1 having the above configuration is connected to, for example, a propeller shaft (not shown).

On the other hand, inside the coupling case 1,
A shaft 6 rotatable about the axis A is arranged. The shaft 6 is formed into a cylindrical shape.
A large diameter portion 7 and a medium diameter portion 8 smaller in diameter than the large diameter portion 7
And a small diameter portion 9 smaller in diameter than the middle diameter portion 8. The large diameter portion 7, the medium diameter portion 8, and the small diameter portion 9
Are sequentially formed in a direction away from the cover 3 side. A plurality of external teeth 7A are formed on the outer periphery of the large diameter portion 7 in the circumferential direction.

A pinion shaft (not shown) of, for example, a differential (not shown) is spline-fitted to the inner periphery of the shaft 6 having the above-described structure. The shaft 6 is formed by an annular bush 10 arranged on the inner periphery of the cover 3.
And one end of the large-diameter portion 6 on the cover 3 side,
An annular plate 11 is arranged between the cover 3 and the inner end surface.

A main clutch 12 is disposed between the inner peripheral surface of the coupling case 1 and the large diameter portion 7 of the shaft 6. The main clutch 12 includes a plurality of clutch discs 13 spline-fitted to the internal teeth 4 of the coupling case 1 and a plurality of clutch plates 14 spline-fitted to the external teeth 7A of the large diameter portion 7. This is a so-called wet multi-plate clutch.

Each of the plurality of clutch disks 13 and the plurality of clutch plates 14 is formed in an annular shape, and the plurality of clutch disks 13 and the plurality of clutch plates 14
And are alternately arranged. The inner diameter of the plurality of clutch disks 13 is set smaller than the outer diameter of the plurality of clutch plates 14.

On the other hand, an annular rotor 15 is provided at a predetermined distance from the main clutch 12 on the open end side of the cylindrical portion 2.
Is arranged. The rotor 15 is rotatable about an axis A. The rotor 15 includes an inner cylindrical portion 16 having a substantially L-shaped cross section in a radial direction, and an annular blocking member fixed to the outer periphery of the inner cylindrical portion 16. 17 and an outer cylindrical portion 18 fixed to the outer periphery of the blocking member 17.

The inner cylinder 16 and the outer cylinder 18 are made of a magnetic material such as iron, and the blocking member 17 is made of a non-magnetic material. The outer cylindrical portion 18 of the rotor 15 is non-rotatably fixed to the inner periphery of the cylindrical portion 2 by welding or the like, and the coupling case 1 and the rotor 15 are integrally rotated. An annular bush 1 is provided on the inner periphery of the inner cylindrical portion 16.
The small diameter portion 9 of the shaft 5 is held by a bush 19.

Further, the end face of the inner cylindrical portion 16 and the shaft 6
The step surface of the middle diameter part 8 and the small diameter part 9 is in contact with each other.
That is, the shaft 6 is sandwiched between the inner cylindrical portion 16 and the plate 11, and the coupling plate 1 and the shaft 6 are positioned in the direction of the axis A.

In the rotor 15 configured as described above, an annular space is formed between the inner cylindrical portion 16 and the outer cylindrical portion 18,
The electromagnet 20 is arranged in this annular space. The electromagnet 20 includes an annular iron core 21 made of a magnetic material,
A coil 22 wound around an iron core 21 and a lead wire 23 for supplying a current to the coil 22 are provided.

The core 21 and the inner cylinder 1 of the rotor 15
6, a radial bearing 24 is mounted, and the electromagnet 20
And the rotor 15 are configured to be relatively rotatable. Further, the electromagnet 20, the rotor 15, and the radial bearing 24 are positioned in the direction of the axis A by the snap ring 25 mounted on the iron core 21 and the snap ring 26 mounted on the inner cylindrical portion 16. Further, the iron core 21 and the rotor 15 are positioned in the radial direction by the radial bearing 24, and an air gap B between the inner periphery of the iron core 21 and the inner cylindrical portion 16;
An air gap C between the outer periphery of the iron core 21 and the outer cylindrical portion 18 is set.

A rotation stopper 28 is attached to the iron core 21 by a screw 27. The rotation stopper 28 is locked to, for example, a part of a differential carrier (not shown) to support the electromagnet 20 so that it cannot rotate. Have been.

An annular coupling oil chamber D is formed in a space surrounded by the cylindrical portion 2, the cover 3, the shaft 6, and the rotor 15 configured as described above. It is enclosed. The coupling oil chamber D is liquid-tightly sealed by a sealing device (not shown).

In the coupling oil chamber D, in addition to the main clutch 12, a pilot clutch 29,
A first cam mechanism 30 and a second cam mechanism 31 are arranged. Hereinafter, the pilot clutch 29, the first cam mechanism 3
0, the configuration of the second cam mechanism 31 will be specifically described.

The pilot clutch 29 is a so-called wet multi-plate clutch having a plurality of clutch disks 32, a plurality of clutch plates 33, and an annular armature 34. The plurality of clutch disks 32 and the plurality of clutch plates 33 are formed in a ring shape and are arranged alternately. The plurality of clutch disks 32 and the plurality of clutch plates 33 are disposed between the armature 34 and the rotor 15. Also, armature 3
Reference numeral 4 is made of a magnetic material.

The first cam mechanism 30 is connected to the pilot clutch 2
9, the first cam mechanism 3
Reference numeral 0 denotes a ring 35 rotatably attached to the outer periphery of the middle diameter portion 8 of the shaft 6, an annular first piston 36 spline-fitted to the external teeth 7A of the shaft 6, a ring 35 and the first piston 36 and a ball 37 disposed between
And

A plurality of clutch plates 33 and armatures 34 are spline-fitted on the outer circumference of the ring 35, and a gap is formed between the ring 35 and the inner cylinder 16 of the rotor 15.
A thrust bearing 38 and an annular plate 39 are interposed. Thus, the ring 35 and the rotor 15
Are configured to be relatively rotatable.

FIG. 2 is a sectional view showing the structure of the first cam mechanism 30. A plurality of trapezoidal grooves 40 and 41 are formed in the circumferential direction on the surface of the ring 35 facing the first piston 36. Have been. Each groove 40, 41 has an inclined surface 42, 43, respectively. A plurality of balls 37 are separately arranged between the grooves 40 and 41.

The second cam mechanism 31 is connected to the main clutch 12
, Specifically, at a position including a projection area in the direction of the axis A of the engagement surface between the plurality of clutch disks 13 and the plurality of clutch plates 14. Further, the second cam mechanism 31 is arranged on the outer peripheral side in the radial direction with respect to the first cam mechanism 30. That is, the first cam mechanism 30 and the second cam mechanism 31 are arranged in parallel on the inner and outer circumferences in the radial direction. The second cam mechanism 31 includes a ring 44 surrounding the outer periphery of the armature 34, an annular second piston 45 disposed between the ring 44 and the main clutch 12, and an opposing surface between the ring 44 and the second piston 45. And a ball 46 disposed therebetween.

The ring 44 has a cylindrical portion 47 disposed on the outer periphery of the armature 34, and an inward flange 48 formed on the cylindrical portion 47. The plurality of clutch disks 32 are spline-fitted on the inner periphery of the cylindrical portion 47.

FIG. 3 is a sectional view showing the structure of the second cam mechanism 31. A plurality of trapezoidal grooves 49 and 50 are separately formed in the circumferential direction on the facing surface of the ring 44 and the second piston 45. Have been. The grooves 49 and 50 are formed with inclined surfaces 51 and 52, respectively. The inclination angle of the inclined surfaces 51 and 52 with respect to the axis A is the inclined surface 4 of the first cam mechanism 30.
The angle is set to be the same as the inclination angle of the axis A with respect to the axis A. A plurality of balls 46 are provided between the grooves 51 and 52.
Are arranged separately. Further, the grooves 51 and 52 and the ball 46 are arranged in a projection area in the direction of the axis A of the engagement surface between the plurality of clutch disks 13 and the plurality of clutch plates 14.

The inner diameter of the second piston 45 is set to be smaller than the outer diameter of the first piston 36, and between the end face of the first piston 36 and the end face of the second piston 45,
A thrust bearing 53 is interposed. The thrust bearing 53 is arranged on the inner peripheral side of the projection area of the engagement surface of the main clutch 12.

Here, the correspondence between the embodiment of FIGS. 1 to 3 and the claims will be described. The coupling case 1 corresponds to the first rotating member of the first embodiment, and the shaft 6 corresponds to the first embodiment.
, The rotor 15, the electromagnet 20, the pilot clutch 29, and the armature 34 correspond to the switching mechanism of the first aspect. In the embodiment shown in FIGS. 1 to 3, the first cam mechanism 30 and the second cam mechanism 31 as a plurality of cam mechanisms are independently constituted by separate parts, and the first cam mechanism 30 The second cam mechanism 31 operates independently to generate a pressing force in the direction of the axis A.

Next, the operation of the driving force transmission device having the above configuration will be described. First, when no current is supplied to the coil 22 of the electromagnet 20, the pilot clutch 29 is released. Therefore, the first cam mechanism 30 and the second cam mechanism 31 are controlled to be in a non-operating state.

That is, the first piston 45 and the ring 44 are integrally rotated by the torque of the coupling case 1, and the pressing force of the second cam mechanism 31 is released. Further, the ring 35 and the first piston 36 are stopped, and the pressing force of the first cam mechanism 30 is released.
Therefore, the main clutch 12 is released, and the torque of the coupling case 1 is not transmitted to the shaft 6.

On the other hand, when an electric current is supplied to the coil 22 of the electromagnet 20, a magnetic circuit connecting the iron core 21, the outer cylinder 18, the inner cylinder 16, and the armature 34 is formed, and the armature 34 is rotated by the magnetic attraction of the electromagnet 20. Move to child 15 side. As a result, the plurality of clutch disks 32 and the plurality of clutch plates 33 are sandwiched between the armature 34 and the rotor 15, and the pilot clutch 29 is engaged.

When the pilot clutch 29 is engaged,
Part of the torque of the coupling case 1 is transmitted to the ring 35 of the first cam mechanism 30 via the rotor 15 and the pilot clutch 29. Then, as shown by an arrow in FIG. 2, the ring 35 and the first piston 36 are rotated relative to each other by a predetermined angle, the ball 37 is sandwiched between the inclined surfaces 42 and 43, and the ring 35 and the first piston 36 are moved in the direction of the axis A. A load is generated to isolate the

Here, since the movement of the ring 35 is restricted by the thrust bearing 33 and the rotor 15, the first
The piston 36 is pressed toward the main clutch 12. That is, the first cam mechanism 30 is controlled to the operating state. The pressing force output from the first cam mechanism 30 is transmitted to the second piston 45 via the thrust bearing 53.

During the above operation, since the first cam mechanism 30 is disposed radially inward of the pilot clutch 29, the torque transmitted from the pilot clutch 29 to the ring 35 is increased in accordance with the radius difference. The pressing force of the first piston 36 is increased.

On the other hand, the engagement of the pilot clutch 29 causes the ring 44 and the second piston 45 to rotate relative to each other by a predetermined angle so that the ball 46 is sandwiched between the inclined surfaces 51 and 52. A load for separating in the A direction occurs. Here, since the movement of the ring 44 in the direction of the axis A is regulated by the rotor 15, the second piston 45 is pressed toward the main clutch 12. That is, the second cam mechanism 31 is controlled to the operating state. Then, the pressing force output from the first cam mechanism 31 acts on the main clutch 12.

Thus, the second piston 45 has:
The pressing force in the direction of the axis A by the first piston 36 and the pressing force in the direction of the axis A by the ball 46 act, and the second piston 45 is operated toward the main clutch 12 by the two pressing forces. As a result, the plurality of clutch discs 13 and the plurality of clutch plates 14 are sandwiched between the second piston 45 and the pressure receiving section 5, and the main clutch 12 is engaged.

As described above, in the embodiment of FIGS. 1 to 3, when the pilot clutch 29 is engaged, a part of the torque of the coupling case 1 is reduced by the first
The power is transmitted to the cam mechanism 30 and the second cam mechanism 31, the first cam mechanism 30 and the second cam mechanism 31 are switched to the operating state, and the pressing force in the direction of the axis A is separately output. Then, the two pressing forces are transmitted to the main clutch 12, and the main clutch 12 is engaged. Therefore, the engaging force of the main clutch 12, that is, the torque capacity is increased as much as possible, and the function of transmitting the torque transmitted from the coupling case 1 to the shaft 6 via the main clutch 12 is improved.

By the way, in this kind of driving force transmission device, as a structure for increasing the engaging force (torque capacity) of the clutch, the number of clutch disks and clutch plates constituting the main clutch or the pilot clutch can be increased. Increasing the radius of the clutch disk and the clutch plate constituting the main clutch or the pilot clutch, changing the angle of the inclined surface of the groove formed in the cam member and the pressing member, increasing the current supplied to the electromagnet, etc. It is conceivable to increase the torque capacity of the main clutch by means of (1).

However, when the number of clutch disks and clutch plates constituting the main clutch is increased, the size of the main clutch increases in the axial direction,
In addition, there is a problem that the weight increases. Further, there is a possibility that the responsiveness of the engagement / disengagement of the main clutch is reduced and the torque transmission function is impaired.

When the number of clutch disks and clutch plates constituting the pilot clutch is increased, the pilot clutch becomes larger in the axial direction, and
There is a problem that the weight increases. Further, since the magnetic attractive force acting on the armature is reduced, an increase in torque capacity in proportion to an increase in the number of clutch disks and clutch plates is not expected.

When the radius of the clutch disk and the clutch plate constituting the main clutch or the pilot clutch is increased, there is a problem that the size of the main clutch or the pilot clutch increases in the radial direction and the weight increases.

When the angle of the inclined surface of the groove formed in the cam member and the pressing member is changed, there is a limit to the change of the angle of the inclined surface of the groove in order to prevent the biting action between the groove and the ball. It is difficult to generate the desired engagement force with the main clutch.

When the value of the current supplied to the electromagnet is increased, there is a problem that the drive circuit of the coil of the electromagnet and the cooling device become large. For this reason, all of the above-mentioned countermeasures are not practical.

On the other hand, in the embodiment shown in FIGS. 1 to 3, the pressing force acting on the main clutch 12 is increased by the first cam mechanism 30 and the second cam mechanism 31. Alternatively, the size and weight of the pilot clutch 29 in the axial direction A or the radial direction are suppressed. Further, the electromagnet 2
In this case, the size of the drive circuit and the cooling device is reduced.

Further, in this embodiment, the second piston 4
5 acts on the main clutch 1.
The second piston 45 is hardly elastically deformed by the first pressing force applied to the second piston 45 from the first piston 36 because the second piston 45 is set within the projection area of the engagement surface 2 in the direction of the axis A. 45 are effectively transmitted to the main clutch 12 so that the main clutch 12
Is increased as much as possible. Therefore, the function of transmitting the torque transmitted from the coupling case 1 to the shaft 6 via the main clutch 12 is further improved. It should be noted that a configuration in which the pressing force of the ball 46 acts on the engagement surface of the main clutch 12 outside the projection area in the direction of the axis A can be employed.

FIG. 4 is a partial front sectional view showing another configuration example of the first cam mechanism 30 and the second cam mechanism 31. In the embodiment of FIG. 4, the path of the pressing force acting on the main clutch 12 from the first cam mechanism 30 and the second cam mechanism 31 is different from the embodiment of FIGS.

In FIG. 4, an outward flange 54 is formed on the outer periphery of the first piston 36 of the first cam mechanism 30. The outer diameter of the outward flange 54 is set to be larger than the inner diameter of the clutch disk 13 of the main clutch 12. The end face of the outward flange 54 and the end face of the clutch plate 14 are arranged to face each other.

On the other hand, the second piston 4 of the second cam mechanism 31
5 is arranged between the ring 44 and the outward flange 54. A thrust bearing 55 is interposed between the end face of the second piston 45 and the end face of the outward flange 54. Other configurations are the same as those of the embodiment of FIGS.

In the embodiment shown in FIG. 4, when the pilot clutch 29 is engaged, the first piston 36 and the second piston 45 are moved in the direction of the axis A by the same operation as the embodiment shown in FIGS. A pressing force for moving the clutch 12 is generated. In the embodiment shown in FIG. 4, the pressing force of the first piston 36 is directly transmitted to the clutch plate 14 of the main clutch 12. On the other hand, the pressing force of the second piston 45 is equal to the thrust bearing 55 and the first piston 36.
Via the main clutch 12. In the case of the embodiment of FIG. 4, the same effects as those of the embodiment of FIGS. 1 to 3 can be obtained.

FIG. 5 is a partial front sectional view showing another configuration example of the first cam mechanism 30 and the second cam mechanism 31. In the embodiment of FIG. 5, the path of the pressing force acting on the main clutch 12 from the first cam mechanism 30 and the second cam mechanism 31 is different from the embodiments of FIGS. 1 to 3 and the embodiment of FIG.

In the embodiment shown in FIG.
Among them, the outer diameter of the clutch plate 14A disposed at a position facing the first cam mechanism 30 and the second cam mechanism 31 is set smaller than the outer diameters of the other clutch plates 14. In addition, a plurality of clutch disks 1
3 is set smaller than the outer diameter of the clutch plate 14A.

Further, the outer diameter of the first piston 36 of the first cam mechanism 30 is set smaller than the outer diameter of the clutch plate 14A and larger than the inner diameter of the clutch disk 13. On the other hand, the outer diameter of the second piston 45 of the second cam mechanism 31 is set to be larger than the outer diameter of the clutch plate 14A.

That is, in the embodiment of FIG. 5, the end face of the first piston 36 and the end face of the clutch disc 14A face each other, and the end face of the second piston 45 and the end face of the clutch disc 13 face each other. . Other configurations are
This is similar to the embodiment of FIGS.

In the embodiment shown in FIG. 5, when the pilot clutch 29 is engaged, the first piston 36 and the second piston 45 are moved in the direction of the axis A by the same operation as the embodiment shown in FIGS. A pressing force for moving toward the clutch 12 is generated. And in the embodiment of FIG.
While the pressing force of the first piston 36 is transmitted to the clutch plate 14A of the main clutch 12, the second piston 4
The pressing force of No. 5 is transmitted to the clutch disc 13 and the main clutch 12 is engaged.

In the embodiment shown in FIG. 5, the same effects as those in the embodiment shown in FIGS. 1 to 3 can be obtained. Further, in the embodiment of FIG. 5, since the pressing force of the first piston 36 and the pressing force of the second piston 45 act on the main clutch 12 separately, the first piston 36 and the second piston 45 No thrust bearing for transmitting the pressing force to each other is required, and the number of parts can be reduced as compared with the embodiment of FIGS. 1 to 3 and the embodiment of FIG.

According to the embodiment shown in FIG. 5, the pressing force of the first cam mechanism 30 and the pressing force of the second cam mechanism 31 separately act on the inner and outer circumferences of the main clutch 12 in the radial direction. As a result, the radial engagement force of the main clutch 12 is made substantially uniform, and a stable torque transmission function is obtained.

In each of the above embodiments, the rotor 15
It is also possible to arrange a thrust bearing between the ring and the ring 44. In the present invention, the pilot clutch 2
It is also possible to convert the engaging force of No. 9 into a pressing force by using three sets of cam mechanisms. For example, in the embodiment of FIG.
Another ring and a third piston are arranged on the outer peripheral side of 7, and the third piston is spline-fitted to the inner periphery of the coupling case 1, and a plurality of clutch plates are provided between the inner periphery of the ring and the ring 35. Arrange multiple clutch discs. Then, a ball is arranged between the third piston and the ring. In this way, the third set of cam mechanisms is arranged,
The configuration is such that the pressing force of the third piston of the cam mechanism is transmitted to the piston 45.

With this structure, the same operation as that of the embodiment shown in FIGS. 1 to 3 is generated, and the pressing force obtained by the third set of cam mechanisms by the engagement of the pilot clutch 29 is applied to the second piston. The power is transmitted to the main clutch 12 via the switch 45. Therefore, the same effect as that of the embodiment shown in FIGS. 1 to 3 can be obtained.

Further, in the present invention, it is also possible to share a part of the components of the plurality of cam mechanisms so as to integrally configure the respective cam mechanisms, and to arrange the respective cam mechanisms in parallel on the inner and outer circumferences in the radial direction. . Specifically, first, the annular ring and the annular piston are arranged in the axial direction, and a plurality of grooves are separately formed on different circumferences of the facing surfaces of the annular ring and the annular piston. Then, a plurality of balls are separately arranged in each groove.

That is, the annular ring and the annular piston are shared, and the groove and the ball are arranged in parallel on the inner and outer circumferences in the circumferential direction. Here, the ring, the piston, the groove, and the ball may be configured substantially the same as those shown in FIGS. The circumferential phase of each groove and each ball arranged on the inner and outer circumferences can be set to match or not match.

[0072]

As described above, according to the present invention, a plurality of cam mechanisms arranged in parallel are switched between an operating state and a non-operating state by the switching mechanism. When the plurality of cam mechanisms are controlled to be in the non-operating state, the pressing force of the plurality of cam mechanisms is released and the clutch is released, so that the transmission of torque between the first rotating member and the second rotating member is prevented. Not done.

On the other hand, when the plurality of cam mechanisms are controlled to operate, the pressing forces are separately output from the plurality of cam mechanisms, and the clutches are engaged by the pressing forces. As a result, the engaging force of the clutch, that is, the torque capacity is increased as much as possible, and the function of transmitting the torque transmitted from the first rotating member to the second rotating member via the clutch is improved.

[Brief description of the drawings]

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

FIG. 2 is a partial cross-sectional view showing a configuration of a first cam mechanism shown in FIG.

FIG. 3 is a partial cross-sectional view showing a configuration of a second cam mechanism shown in FIG.

FIG. 4 is a partial front sectional view showing another embodiment of the driving force transmission device of the present invention.

FIG. 5 is a partial front sectional view showing still another embodiment of the driving force transmission device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coupling case 6 Shaft 12 Main clutch 15 Rotor 20 Electromagnet 29 Pilot clutch 30 1st cam mechanism 31 2nd cam mechanism 34 Armature

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Mitsuru Ooba 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (2)

[Claims] A first rotating member and a second rotating member disposed so as to be relatively rotatable; a clutch for controlling transmission of torque between the first rotating member and the second rotating member; A driving mechanism including a cam mechanism capable of switching between an operating state for outputting a pressing force to be engaged and a non-operating state for releasing the pressing force, and a switching mechanism for switching the cam mechanism between an operating state and a non-operating state. A transmission device, wherein a plurality of the cam mechanisms are arranged, and each cam mechanism is arranged in parallel. 2. The driving force transmission device according to claim 1, wherein the cam mechanisms are arranged in parallel on the inner and outer circumferences in a radial direction.