JPH11325219A - Clutch operating mechanism and power transmission therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clutch operating mechanism for fastening a clutch in a simple structure, holding it in a fastened condition and reducing its cost accordingly and a power transmission therewith. SOLUTION: A differential device 1 includes a bevel gear differential mechanism 31 stored in a differential case, an inner clutch 25 for fixing and supporting a pinion shaft 33 of a differential mechanism 31 and an outer clutch 15 supported by the differential case 7 to be integrally rotated and supported to be movable to the direction of a shaft. A clutch operating mechanism 35 for fastening both clutches 25, 15 includes a cam mechanism 34, an electric motor 37 for driving and engaging the cam mechanism 34 via a transmission mechanism 40 and a cam for holding the cam mechanism 34 in an engaged condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch operating mechanism and a power transmission having the mechanism.

[0002]

2. Description of the Related Art As an example of a conventional clutch operating mechanism and a power transmission device having the same, for example, a differential device shown in FIG. 13 is disclosed in Japanese Patent No. 2529245.

The differential device 401 has four
At the time of WD, it functions in the same manner as a normal differential device. It is configured not to be rotated from the axles 409, 411 side.

[0004] The operation mechanism 413 of the dog clutch 407 for interrupting the power transmission path in the differential device 401 in accordance with the switching between 4WD / 2WD is configured as follows.

That is, a ring 415 is rotatably arranged inside the outer differential case 405, and a slide gear 417 is arranged adjacent to the left of the ring 415. The slide gear 417 is engaged with the groove 419 on the inner wall of the differential case 405 to rotate integrally with the differential case 405 and to be movable in the axial direction.

The ring 415 and the slide gear 41
7, dog dogs 423 and 423 of a dog clutch 407 which are engaged / disengaged by the axial movement of the slide gear 417.
421 are provided respectively. At the time of 4WD, the dog clutch 407 is engaged, and the differential case 405 and the ring 417 are engaged.
And the dog clutch 407 at 2WD
And the differential case 405 and the ring 417 are separated.

On the other hand, a pinion shaft 425 is fixed to the ring 417. A pinion gear 427 is rotatably supported on the pinion shaft 425, and meshes with a pair of output side gears 429 and 431. Left and right axles 409, 411 are connected to the side gears 429, 431. Thus, when the differential case 405 and the ring 417 rotate integrally (at the time of 4WD), they function as a differential device.

The operation mechanism 413 for moving the slide gear 417 is configured as follows. That is, for example, a hydraulic cylinder 435 fixed to a differential carrier 433 that rotatably supports the differential device 401.
Then, when hydraulic pressure is applied from a pump (not shown) via a hose 437, the fork 441 moves rightward integrally with the piston 439, and the thrust bearing 443 and the spring 445 are moved.
To push the slide gear 417 rightward to engage the dog clutch 407. When the hydraulic pressure is released, the slide gear 417 returns due to the urging force of the return spring 447, the dog clutch 407 disengages, and the power transmission path in the differential device 401 is disconnected.

[0009]

As described above, the operating mechanism 413 of the dog clutch 407 includes the hydraulic pump and the hose 437.
, The hydraulic cylinder 435, the piston 439, the fork 441, etc., and the configuration is complicated and the cost is high. Further, at the time of 4WD, there is a problem that a holding mechanism for holding the hydraulic pressure for engaging the dog clutch 407 is also required separately.

Accordingly, an object of the present invention is to provide a clutch operating mechanism capable of operating the clutch with a simple configuration and holding the clutch in the engaged state, thereby reducing the cost, and a power transmission device provided with the same. And

[0011]

According to a first aspect of the present invention, there is provided a cam mechanism for engaging and operating a clutch, and driving the cam mechanism via a transmission mechanism to control the cam mechanism. An electric motor to be engaged is provided, and holding means for holding the cam mechanism in an engaged state is provided.

Therefore, even if the electric motor is turned off after the engagement of the cam mechanism, it is not necessary to maintain the engaged state by special means, and the clutch can be maintained in the engaged state by the engaged state retaining means.

[0013] In this manner, the clutch can be operated with a simple structure and can be held in that state, so that the cost can be reduced accordingly.

According to a second aspect of the present invention, there is provided the clutch operating mechanism according to the first aspect, wherein the holding means is provided on cam portions which engage with each other when the cam mechanism is engaged. And

Therefore, the same operation and effect as those of the first aspect can be obtained by providing the engagement portion holding means on the cam portion of the cam mechanism without separately providing it.

According to a third aspect of the present invention, in the clutch operating mechanism according to the first aspect, the holding means is a worm gear mechanism provided in the transmission mechanism.

Therefore, the engagement state can be held by utilizing the reverse drive preventing action of the worm gear mechanism without separately providing the engagement state holding means, and the same operation and effect as the first aspect of the invention can be obtained. Can be

According to a fourth aspect of the present invention, there is provided the clutch operating mechanism according to the second aspect, wherein the holding means abuts each other when the cam portion is engaged and a force in the relative movement direction after the abutment. This is a flat part having an angle at which no angle occurs.

Therefore, when the cam portion is engaged, the flat portions come into contact with each other, and no force for relative movement is generated due to the angle thereof, so that the same operation and effect as the second aspect of the invention can be obtained.

According to a fifth aspect of the present invention, in the clutch operating mechanism according to the second aspect, the holding means is formed in a concave portion formed in one cam portion and a cam portion formed in the other cam portion. And a projection which is engaged with the recess when engaged.

Accordingly, when the two cam portions are engaged, the projection of the other cam portion is locked in the concave portion of the one cam portion, thereby maintaining the engaged state. The operation and effect of are obtained.

According to a sixth aspect of the present invention, there is provided the clutch operating mechanism according to the third aspect, wherein each cam portion constituting the cam mechanism has a tongue portion formed on an inclined surface having substantially the same angle. And a clutch operating mechanism in which both tongues are inclined and faced in the same direction.

Therefore, even if a force in the disengagement direction is generated due to the inclination of the tongue portions of the two cam portions engaged with each other, the cam portion is held in the engaged state by utilizing the reverse drive preventing action of the worm gear mechanism. The same operations and effects as those of the invention described in Item 3 are obtained.

Further, the cost can be more effectively reduced by a simple structure in which the tongue portions are formed on both cam portions.

According to a seventh aspect of the present invention, there is provided the clutch operating mechanism according to any of the second to sixth aspects, wherein the cam portion is formed of a plate-like member.

Therefore, the same operation and effect as those of any of the second to sixth aspects can be obtained, and the plate-like member can be formed by, for example, press molding, so that the weight can be reduced and the manufacturing cost can be reduced. Becomes

The invention according to claim 8 is a bevel gear type differential mechanism housed in a differential case that is rotationally driven by the driving force of an engine, and a pinion shaft of the differential mechanism housed rotatably in the differential case. A differential clutch device, comprising: a clutch member on one side fixedly supporting the clutch case; and a clutch member on the other side supported to rotate integrally with the differential case and movably supported in a rotation axis direction. A clutch operating mechanism according to any one of claims 1 to 7, wherein the clutch operating mechanism engages both clutch members.

Therefore, the operation and effect of the clutch operating mechanism according to any one of claims 1 to 7 can be obtained, and the structure of the bevel gear type differential device is simplified, so that the cost can be reduced.

According to a ninth aspect of the present invention, there is provided an output shaft on one side and an output shaft on the other side which are rotatably supported in a transfer case and are connected to each other via a transmission mechanism. And a power transmission to one of the output shafts and the other of the output shafts, and a drive-side clutch member that rotates integrally with the one output shaft. And a driven clutch member rotatably supported on the one output shaft, and the clutch operating mechanism according to any one of claims 1 to 7 for engaging and operating the two clutch members. Features.

Accordingly, the operation and effect of the clutch operating mechanism according to any one of claims 1 to 7 can be obtained, and the structure of the transfer device is simplified, so that the cost can be reduced.

According to a tenth aspect of the present invention, there is provided a differential mechanism comprising a pinion gear and a side gear housed in a differential case rotatably driven by the driving force of the engine, and one side provided on the pinion gear or the side gear of the differential mechanism. And a clutch member on the other side that is supported so as to rotate integrally with the differential case and that is supported movably in the direction of the rotation axis, wherein the two clutch members are engaged with each other. A clutch operating mechanism according to any one of claims 1 to 7 is provided.

Therefore, the operation and effects of the clutch operating mechanism according to any one of claims 1 to 7 can be obtained, and the configuration of, for example, a parallel shaft type differential device can be simplified, and the cost can be reduced.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of a clutch operation mechanism 35 of the present embodiment and a differential device 1 as a power transmission device including the same.
FIG. 2 is an enlarged view of a main part.

This differential device 1 is a differential device disposed on the axle on the side where the driving force from the engine is cut off at the time of 2WD of a part-time 4WD vehicle, similarly to the differential device 401 (FIG. 12) of the conventional example. is there.

As shown in FIG. 1, the differential device 1 is rotatably supported by a differential carrier 5 via bearings 3 and 3, and a differential case 7 is rotationally driven by the driving force of the engine. The differential case 7 includes a differential case main body 9 and a cover 11 connected by screws 13. A plurality of openings 7b are provided in the right end wall 7a of the differential case 7 in the circumferential direction and penetrate in the axial direction.

An outer clutch (the other clutch member) 15 is disposed in the opening 7b so as to penetrate the leg 15a, and rotates integrally with the differential case 7. A dog 15b of a dog clutch 17 (clutch) is formed on the inner end face of the outer clutch 15, and is integrally attached to the inner circumference of a retainer 21 having an L-shaped cross section on the outer end face.
The outer clutch 15 is movable in the axial direction.

An inner clutch (one side clutch member) 25 is rotatably fitted to the inner periphery 7c of the cylindrical portion of the differential case 7, and a dog 25b of a dog clutch 17 and a dog of the outer clutch 15 are provided on the right end face of the inner clutch 25. Fifteen
b. The engagement of the dog clutch 17 is interrupted by the axial movement of the outer clutch 15.

A pinion shaft 33 is fixed to the inner clutch 25 at right angles to the rotation axis of the differential case 7. A pinion gear 3 is provided on the pinion shaft 33.
2 is rotatably supported, and the pinion gear 35 meshes with a pair of output side gears 36 and 38 that are arranged to face each other. When the dog clutch 17 is engaged, the inner clutch 25 rotates integrally with the differential case 7. Thus, the bevel gear type differential mechanism 31 is configured.

The operating mechanism 35 for engaging the dog clutch 17 is connected to the right end wall 7a of the differential case 7 and the differential carrier 5
The boss portion 5a is arranged as follows, and is configured as follows.

A stepping motor (electric motor) 37 is mounted on the boss 5a of the differential carrier 5, and the motor 3
The drive gear 39 is fixed on the output shaft 7. The stepping motor 37 repeats forward rotation and reverse rotation within a predetermined rotation speed range described later. The transmission mechanism 40 includes a drive gear 39 and a cam gear 45 described later. The stepping motor 37 may be arranged outside the differential carrier 5.

The cam mechanism 34 is configured as follows. That is, the base 41 a of the cam member 41 is fixed on the boss 5 a by the bolt 43. Cam member 4
1 includes a cam portion 41b which is bent substantially at right angles to the base portion 41a and extends toward the axial center.
A cylindrical portion 41c extending toward the differential case 7 at the small diameter portion b is provided. Then, the differential case 7 of the cam portion 41b
2a are provided at a plurality of locations on the opposite surface of FIG. This cam is a fixed cam 42. The fixed cam 42 is press-moldable.

A substantially disk-shaped cam gear 45 is rotatably supported on the cylindrical portion 41c, and the cam gear 45 is supported movably in the axial direction. The cam gear 45 meshes with the drive gear 39 on the stepping motor 37 side and rotates at a reduced speed. Further, the cam gear 45 has a convex cam shown in FIG. 2A on a surface of the cam member 41 facing the cam member 41, which is simultaneously engaged with each fixed side cam 42 of the cam member 41. This cam is a rotation side cam 46.

FIG. 2A shows a state in which the engagement between the cams 42 and 46 is released (free state). At this time, the cam gear 4
5 is pressed by the cam member 41 by the urging force of a return spring 47 (described later), and the top 46 of the cam 46 of the cam gear 45 is moved.
a contacts the bottom 42 b of the cam 42 of the cam member 41.

FIG. 2B shows the engaged state (locked state) of the cams 42 and 46. At this time, the tops 42a, 46a of both cams 42, 46 abut. Each of the tops 42a, 46a
Are formed on a plane perpendicular to the axis. Also, the cam member 41
The projection 42c formed on the top 42a of the cam 42 contacts the concave portion 46c formed on the top 46a of the cam gear 45. The projection 42c and the recess 46c are formed in a part of the axial width of the cam member 41 and the cam gear 45.

Thus, the two cams 42 and 46 constitute the holding means in the engaged state, that is, the holding means in the engaged state of the dog clutch 17.

The back of the cam gear 45 and the outer clutch 15
A thrust bearing 49 is interposed between the retainer 21 and the thrust bearing 49. A return spring 47 is interposed between the right end wall 7a of the differential case 7 and the retainer 21, and the outer clutch 15 (retainer 21) is constantly biased rightward by the return spring 47.

Next, the operating mechanism 35 of the dog clutch 17
The operation of the differential device 1 will be described.

When the 4WD / 2WD switching device (not shown) is set to 4WD, the stepping motor 37 rotates in conjunction with the setting, and the rotation side cam 46 rotates with the rotation of the cam gear 45 meshing with the drive gear 39. When moving from the free state (FIG. 2A) in the direction of arrow A to reach the engaged state with the fixed cam 42 (FIG. 2B), the stepping motor 37 stops by the rotation speed control. Note that the cam 42 may be stopped by detecting a current value or a temperature rise when the projection 42c at the top of the cam comes into contact with the recess 46c. Alternatively, a separate limit switch may be provided to stop after the engagement. According to these stopping methods, low cost general D
A C motor can be used.

At this time, the cam gear 45 is connected to the return spring 4
7 to the left against the urging force of the outer clutch 15
And the dog clutch 17 between the inner clutch 25 is engaged. As a result, the inner clutch 25 rotates integrally with the differential case 7, so that the differential mechanism 31 differentially distributes the driving force of the engine to the left and right axles.

At this time, the cam member 41 and the cam gear 4
Since the tops 42a, 46a formed in a plane perpendicular to the rotation axes of the cams 42, 46 of the fifth member are in contact with each other, no force is exerted to break the contact state, and it is not necessary to provide a special holding mechanism.

When the 4WD / 2WD switching device is switched and set to 2WD, the stepping motor 37 rotates in the opposite direction in conjunction with the switching setting, and
When 6 moves in the direction B in FIG. 2B and returns from the engaged state to the free state (FIG. 2A), the rotation stops.

At this time, the cam gear 45 is connected to the return spring 4
7, the dog clutch 17 between the outer clutch 15 and the inner clutch 25 is released. As a result, the inner clutch 25 can rotate relative to the differential case 7, so that the power transmission path in the differential device 1 is disconnected. In the 2WD state, the inner clutch 25 is rotated by the left and right axles via the side gears 36 and 38, the pinion gear 35, and the pinion shaft 33, but the differential case 7 does not need to rotate.

Thus, at the time of 2WD, noise is reduced, and fuel consumption is improved by reducing the number of rotating parts.

Thus, according to the present embodiment, the dog clutch 17 is operated by the operation mechanism 35 having a simple structure including the stepping motor 37, the transmission mechanism 40, and the cam mechanism 34.
, And the engagement is maintained by the abutment of the top portions 42a, 46a of the cams 42, 46 on the fixed side and the rotation side, so that the cost of the clutch operation mechanism is reduced accordingly.

The fixed cam 42 can be reduced in weight and improved in productivity by press molding.

[Second Embodiment] A second embodiment of the present invention will be described with reference to FIGS. 3 and 4 are cross-sectional views of the clutch operation mechanism 135 of the present embodiment and the differential device 101 as a power transmission device including the same, and FIGS. 5 to 7 are enlarged views of main parts.

This differential device 101 is a differential device arranged on the axle on the side from which the driving force from the engine is cut off at the time of 2WD of a part-time 4WD vehicle, similarly to the above-described conventional differential device 401 (FIG. 12). is there.

The differential device 101 differs from the first embodiment in the operation mechanism 135 of the dog clutch 17, and the other configuration is the same as that of the first embodiment. Therefore, only the differences will be described, and members having the same functions will be denoted by the same reference numerals, without redundant description.

As shown in FIGS. 3 and 4, in the differential device 101, the operating mechanism 135 for engaging the dog clutch 17 is configured as follows.

The stepping motor 37 is the differential carrier 5
The output shaft 37a of the motor 37 is extended and penetrates into the differential carrier 5, and a drive gear 39 is fixed to an end of the output shaft 37a in the differential carrier 5. On the other hand, the base 141 a of the plate-like cam member 141 is fixed on the boss 5 a of the differential carrier 5 with a bolt 43. The cam member 141 includes a cam portion 141b which is bent substantially at right angles to the base portion 141a and extends toward the axial center, and further includes a differential case 7 having a small diameter portion of the cam portion 141b.
A cylindrical portion 141c extending to the side (to the left) is provided.

The cam portion 141b has a plurality of convex cams 142 shown in FIG. 5a on the surface of the cam portion 141b facing the differential case 7 at equal circumferential positions. Top 142 of cam 142
a is formed in a planar shape. FIG. 5A shows this cam 141.
Part b is shown expanded in the circumferential direction. The cam is press formed with a cut. This cam is the fixed cam 142.

A cam gear 145 press-formed on the cylindrical portion 141c is rotatably supported.
45 is movably supported in the axial direction. Cam gear 14
5 meshes with the drive gear 39 on the stepping motor 37 side and rotates at a reduced speed. Each cam 142 of the cam member 141 is provided on a surface of the cam gear 145 facing the cam member 141.
And the convex cam 1 shown in FIG.
46. The cam 146 has a middle portion 146a formed in a planar shape. Thus, this cam is the rotating cam 146. Middle abdomen 146a of rotating cam 146
Is engaged with the top 142a of the fixed cam 142,
The convex portion 146b of the rotating cam 146 contacts the top 142a of the fixed cam 142, and the rotation of the stepping motor 37 stops.

In this embodiment, as in the first embodiment, another stopping method can be employed, and a low-cost DC motor can be used.

FIG. 5A shows a state in which the engagement between the cams 142 and 146 is released (free state). At this time, the cam gear 145 is rotated in the direction of arrow B from the previous engaged state (FIG. 5B) by the rotation of the stepping motor 37 to become a free state, and the cam member 141 is biased by the return spring 47 (see FIG. 4). Abut

Both cams 142 and 146 are formed so that the slope portions of the cams 142 and 146 which are in sliding contact with each other are formed to be gentler than the other side, so that the engagement is facilitated. The inclination of the other slope is set to a steep inclination, and the cams 142, 1 when the stepping motor 37 rotates in the reverse direction are set.
46 are prevented from getting on.

In this manner, the holding means in the engaged state, that is, the holding means in the engaged state of the dog clutch 17 is constituted by the two cams 142 and 146.

Next, the operating mechanism 13 of the dog clutch 17
5 and the operation of the differential device 101 will be described.

When the 4WD / 2WD switching device (not shown) is set to 4WD, the stepping motor 37 rotates in conjunction with the setting, and the rotating cam 146 of the cam gear 145 meshing with the driving gear 39 causes the cam member 141 to rotate. From the free state (FIG. 5A) with respect to the fixed side cam 142 of FIG.
(FIG. 5B), the middle part 146a of the rotating cam 146 contacts the top 142a of the fixed cam 142, and the convex part 146b of the rotating cam 146 contacts the top 142a of the fixed cam 142. Then, the stepping motor 37 stops.

By the engagement of the cams 142 and 146, the cam gear 145 presses and moves the outer clutch 15 to the left (toward the differential case 7) against the urging force of the return spring 47, and the dog clutch 17 is engaged. FIG. 3 shows the differential device 101 in this fastening state.

When the 4WD / 2WD switching device is switched and set to 2WD, the stepping motor 37 rotates in the opposite direction to the above in conjunction with the switching setting, and the rotating cam 1
When 46 moves from the engaged state (FIG. 2b) in the direction B (FIG. 5a) and returns to the free state, the rotation stops.

At this time, the cam gear 145 moves rightward by the urging force of the return spring 47, and the outer clutch 15
The engagement of the dog clutch 17 between the and the inner clutch 25 is released. FIG. 4 shows the differential device 101 in the disengaged state.

The structure of the cam is different from the above (FIG. 5), and may be, for example, the structure shown in FIGS.

FIG. 6A shows a state in which the rotation side cam 146 'has moved in the direction of arrow B to disengage the cam and enter the free state. FIG. 6B shows an engagement state in which the rotation side cam 146 'is moved in the direction A by the reverse rotation of the stepping motor 37 and is engaged with the fixed side cam 142'.

In this case, as shown in FIG.
2 'is formed in a trapezoidal shape, and a slit (recess) 142b' orthogonal to the rotation direction of the cam gear 145 'is formed in the center of the planar top 142a'. On the other hand, the rotating cam 146 'is formed in a trapezoidal shape, and a tongue 146b' is formed at the center of the top 146a 'so as to protrude.
6B, the tongue 146b 'is locked in the fixed side slit 142b'. Cam gear 4
The tongue 146b 'bent by the fixed cam 142' with the movement of 5 partially recovers the bending at the position of the slit 142b 'and is locked and engaged. Therefore, in this engaged state, the tongue portion 146b 'has a restoring force against bending, and this restoring force presses the dog clutch 17 in the fastening direction, so that the dog clutch 17 is more securely fastened.

FIG. 7A shows a state in which the rotation side cam 146 "is in a free state by the movement of the rotation side cam 146" in the direction of arrow B. FIG. 7B shows an engagement state in which the rotation side cam 146 ″ moves in the direction of arrow A by the reverse rotation of the stepping motor 37 and engages with the fixed side cam 142 ″. Both the cams 142 "and 146" are formed in a trapezoidal shape and have planar tops 142a "and 146a".

In both cases of FIGS. 6 and 7, the slopes of the slopes (142b "and 146b" in FIG. 7) which come into sliding contact at the time of engagement are formed to be gentler than the other side, so that engagement is facilitated. ing. The slope of the other slope is set to a steep slope to prevent the cam from running up when the engagement is released.

In this embodiment, as shown in FIG. 5, both cams 142 and 146 have a simple cam shape.
A stepping motor 37 is combined as an electric motor.

Thus, according to this embodiment, the first
The same operation and effect as those of the embodiment can be obtained, and since the cam member 141 and the cam gear 145 are press-formed, the weight can be reduced and the productivity can be improved.

[Third Embodiment] A third embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a cross-sectional view of the clutch operation mechanism 235 of the present embodiment and a differential device 201 as a power transmission device including the same.
9 and 10 are enlarged views of a main part. This differential device 201 is a differential device arranged on the axle on the side where the driving force from the engine is cut off at the time of 2WD of a part-time 4WD vehicle, similarly to the differential device 401 (FIG. 12) of the conventional example.

The differential device 201 is different from the first embodiment in the operation mechanism 235 of the dog clutch 17, and the other configuration is the same as that of the first embodiment. Therefore, only the differences will be described, and members having the same functions will be denoted by the same reference numerals, without redundant description.

As shown in FIG. 8, in the differential device 201, the operation mechanism 235 of the dog clutch 17
Is configured as follows.

The stepping motor 37 is connected to the differential carrier 5
And the worm 2 is fixed on the output shaft of the motor 37.
The worm wheel 240 is fixed to one end of a worm wheel shaft 240a disposed orthogonal to the output shaft. The worm wheel 240 meshes with the worm 239. I have. The drive gear 39 is fixed to the other end of the worm wheel shaft 240a. Then, the drive gear 39 meshes with the cam gear 245, and is further reduced in speed.

A fixed cam 242 (see FIG. 9) is formed on the cam member 241 fixed to the boss portion 5a of the differential carrier 5, and a fixed cam 242 is formed on the adjacent cam gear 245.
The rotation side cam 246 which engages with is formed.

FIG. 9A shows a state in which the rotating cam 245 moves in the direction of arrow B to release the engagement of the cam and enter a free state. FIG. 9B shows an engagement state in which the rotation side cam 246 moves in the direction of arrow A by the reverse rotation of the stepping motor 37 and engages with the fixed side cam 242.

In this case, as shown in FIG.
2 is formed in a trapezoidal shape, and has a hole 242c adjacent to a slope (cam surface) 242b having a gentle inclination angle on the front side of the engagement of the fixed cam 242. On the other hand, the rotation side cam 246 has a flat middle portion 246a and a convex portion 246c protruding from the middle portion 246a.
The slope (cam surface) 246b having a gentle inclination angle is located on the near side of the engagement of
have.

In the free state (FIG. 9A), the projection 246c of the rotating cam 246 is
42c, and the flat top 242a of the fixed cam 242 is in contact with the bottom surface 246d of the rotating cam 246. Due to the structure in which the protrusion 246c falls, the protrusion 24
The protrusion height of 6c can be set large, so that slip prevention and holding action after engagement can be obtained more reliably.

In the engaged state where the rotating cam 246 has moved in the direction of arrow A from this free state, the rotating cam 246 has
And the flat top 242a of the fixed side cam 242 abuts.

Thus, the holding means in the engaged state, that is, the holding means in the engaged state of the dog clutch 17 is constituted by the two cams 242 and 246.

The structure of the cam is different from the above (FIG. 9), and may be, for example, the structure shown in FIG. in this case,
Tongue portions 242a ', 246 bent at the same inclination angle on fixed side cam 242' and rotating side cam 246 ', respectively.
a 'are arranged facing each other while being inclined in the same direction. FIG.
Shows a free state in which the engagement of the tongue portions 242a 'and 246a' is released, and FIG. 10b shows an engaged state.

In the engaged state shown in FIG. 10B, both cams 242 ',
Since the tongues 242a 'and 246a' of the 246 'are in contact with each other, the rotating cam gear 245'
The force to shift to the free state is received by the urging force of 7,
Reverse driving is prevented by setting the meshing friction of the worm gear mechanism 238, and the two cams 242 'and 246' can be held in the engaged state.

With this configuration, according to this embodiment, the same operation and effect as those of the first embodiment can be obtained, and the productivity is improved because the cam member 241 and the cam gear 245 are press-formed.

[Fourth Embodiment] A fourth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a cross-sectional view of the clutch operation mechanism 335 of the present embodiment and a transfer device 301 as a power transmission device including the same.

The transfer device 301 switches between 4WD and 2WD by engaging and disengaging the dog clutch 17 by the clutch operating mechanism 335. Clutch operation mechanism 33
5 is the same as in the first embodiment, and a duplicate description will be omitted.

The transfer case 301 is composed of a front case 309 and a rear case 311 connected by bolts 313, and rotatably supports, for example, an output shaft 337 on the rear wheel side via bearings 303, 303.
Output shaft 33 on the front wheel side via bearings 351 and 351
9 is rotatably supported. Both output shafts 337, 339
Are arranged in parallel, and a drive side clutch member 315 rotatably supported on an output shaft 337 and a driven side sprocket 353 formed integrally with the output shaft 339 are connected via a chain transmission mechanism 355. .

The driving force input to the left end portion 337a of the output shaft 337 on the rear wheel side is transmitted to the rear axle side via a coupling flange 357 spline-connected to the right end portion 337b. At the time of fastening of the output shaft 3 on the front wheel side via the chain transmission mechanism 355.
Also transmitted to the front axle side via a coupling flange 341 that is splined to the left end 339a of the output shaft 339.

A dog 315b for engaging the dog clutch 17 is formed at one end of the driving side clutch member 315 on the rear wheel output shaft 337, and a driven clutch member having a dog 325b engaged and disengaged from the dog 315b. 325 is splined on the output shaft 337 on the rear wheel side. The clutch member 325 is constantly urged by the return spring 47 in a direction in which the engagement of the dog clutch 17 is released.

An operating mechanism 335 for engaging and disengaging the dog clutch 17 is arranged adjacent to the clutch member 325 on the side opposite to the dog 325b, and is configured as follows.

The stepping motor 37 is fixed outside the transfer case 301, and the output shaft 37 of the motor 37 is
a is extended and penetrates into the differential carrier 5, and a drive gear 39 is fixed to an end of the output shaft in the transfer case 301. The drive gear 39 is engaged with a cam gear 345 described later on the output shaft 337 side.

On the other hand, a bearing 339 is provided on the output shaft 337.
The fixed side cam member 341 is rotatably supported through the boss portion 305 a of the transfer case 301 and is integrated in the rotation direction. Cam member 34
1 has the fixed side cam 342 (see FIG. 2) described in the first embodiment formed on the opposite side surface (right side surface) of the boss portion 305a, and rotates the cam gear 345 on the hollow shaft 341c. We support as much as possible.

A rotating cam 346 is formed on a surface of the cam gear 345 facing the fixed cam 342.
The rear side of 6 faces the clutch member 325 via the thrust bearing 349. The cams 342 and 346 may have the same shape as the cams 42 and 46 of the first embodiment, for example.

Thus, the engagement means, that is, the engagement means of the dog clutch 17 is constituted by the cams 342 and 346.

Next, the operation mechanism 33 of the dog clutch 17
5 and the operation of the transfer device 401 will be described.

The stepping motor 37 is driven by the rotating cam 34.
6 rotates in the direction in which the fixed side cam 342 engages, the two cams 342 and 346 are engaged, and the clutch member 325 is pressed rightward by the rotating side cam 346 via the thrust bearing 349, and the dog clutch 17 is moved. To conclude. Thus, the driving force is also transmitted from the driving side sprocket 315 to the output shaft 339 on the front wheel side via the chain transmission mechanism 355.

Then, by the reverse rotation of the stepping motor 37, the rotating cam 34 is biased by the urging force of the return spring 47.
6 returns to the left, and the engagement of the dog clutch 17 is released. Thus, the transmission of the driving force to the front wheel side output shaft 339 is cut off.

As described above, according to the present embodiment, the same operation and effect as those of the first embodiment can be obtained also in the transfer device 301.

[Fifth Embodiment] A fifth embodiment of the present invention will be described with reference to FIG. FIG. 12 is a cross-sectional view of the clutch operation mechanism 365 of the present embodiment and a differential device 361 as a power transmission device including the same.

In the differential device 361, the operation mechanism 365 of the dog clutch 363 has the same configuration as that of the operation mechanism 135 (FIGS. 3 and 4) of the second embodiment, and the differential gear mechanism is different from that of the second embodiment. Therefore, the differences will be described, and members having the same functions will be assigned the same reference numerals,
Duplicate description will be omitted.

As shown in FIG. 12, the differential device 361 has a parallel shaft type differential gear mechanism 367. The differential case 369 to which the driving force of the engine is input has a case body 369a and a cover 369b formed by bolts 371.
Boss portions 369c, 369 at both ends.
At d, it is rotatably supported by the Teff carrier 373 via a bearing (not shown).

In the differential case 369, the differential case 36
Left and right side gears 375 and 377 are rotatably opposed to each other coaxially with the output shaft 9, and an output shaft (not shown) is spline-connected to the inner periphery of each side gear 375 and 377.
The two side gears 375 and 377 are centered by opposing centering portions 379, and a thrust block 381 is disposed on the opposing inner peripheral portion.

The differential case 369 around the side gears 375, 377 is provided with a plurality of pairs of long and short storage holes 383, 385.
9 is slidably supported. Double pinion gear 38
7, 389 are prevented from falling off by a plate 369e attached to the differential case 369.

The long pinion gear 387 includes first and second gear portions 387a and 387b and an intermediate small-diameter shaft portion 387.
c, and the first gear portion 387a has the right side gear 37
7 is engaged. In the short pinion gear 389, the right end gear portion 389a meshes with the left side gear 375, and the left end gear portion 389b meshes with the second gear portion 387b of the long pinion gear 387. Thus, both side gears 375, 377 are connected.

The dog clutch 363 is configured as follows. An inner clutch (one side clutch member) 377a is integrated with the right side gear 377,
A dog 377b is formed on an outer end surface of the inner clutch 377a. The outer clutch (the other clutch member) 391 is provided by being disposed in a concave portion of the inner wall of the cover 369b of the differential case 369 and penetrating the leg portion 391a into a through hole 369f provided in the wall of the cover 369b. .

Thus, the outer clutch 391 is integrated with the differential case 369 in the rotational direction,
9 is movable in the axial direction. Outer clutch 391
A dog 391b is formed on the inner end face of the
1b faces the dog 377b of the inner clutch 377a. Inner clutch 377a and outer clutch 39
Reference numeral 1 designates both dogs 3 by a return spring 47 disposed in the middle.
77b and 391b are urged in a direction in which the engagement is released.

The inner clutch 377a may be integrated with the long pinion gear 387 instead of being integrated with the right side gear 377.

A plate 393 is screwed to the outer end surface of the outer clutch 391, and the plate 393 is in sliding contact with the cam gear 145.

Next, the operating mechanism 3 of the dog clutch 363
The operation of the differential 65 and the differential device 361 will be described.

When the stepping motor 37 does not rotate, the dog clutch 36 is driven by the urging force of the return spring 47.
3 is released, and the differential gear mechanism 367 differentially distributes the driving force of the engine to the left and right side gears 375, 377. Thus, the left and right side gears 375 and 377 can be rotated differentially.
The vehicle provided with 61 enables smooth turning.
FIG. 12 shows this state of the differential device 361.

When the stepping motor 37 rotates, the cam gear 145 meshing with the drive gear 39 rotates. With the rotation of the cam gear 145, the rotating cam 146 of the cam gear 145 moves from the free state (FIG. 5A) to the fixed cam 142 of the cam member 141 in the direction of arrow A (FIG. 5).
b), the middle part 146a of the rotating cam 146 contacts the top 142a of the fixed cam 142, and the convex part 146b of the rotating cam 146 contacts the top 142a of the fixed cam 142. 37 stops.

By the engagement of the cams 142 and 146, the cam gear 145 presses and moves the outer clutch 391 to the left (toward the differential case 369) against the urging force of the return spring 47, and the dog clutch 363 is engaged. Since both cams 142 and 146 are held in this engaged state,
The dog clutch 363 is held in the engaged state.

When the dog clutch 363 is engaged, the differential case 369 and the right side gear 377 cannot rotate relative to each other and rotate integrally, so that the left side gear 375 is also rotated via the pinion gears 387, 389. The same rotation as the side gear 377), the differential operation of the differential gear mechanism 363 is disabled. That is,
The differential device 361 is in a differential lock state.

As described above, according to the present embodiment, the operating mechanism 3 is also used in the parallel shaft type differential device 361.
The function and effect equivalent to those of the second embodiment can be obtained by 65, and the mechanism of the differential lock operation and the release operation thereof can be simplified by the operation mechanism 365, and the cost can be reduced.

[0122]

As is apparent from the above description, according to the first aspect of the present invention, even if the electric motor is turned off after the engagement of the cam mechanism, it is necessary to maintain the engaged state by special means. However, the clutch can be held in the engaged state by the engagement state holding means.

In this manner, the clutch can be operated with a simple structure and can be held in that state, so that the cost can be reduced accordingly.

According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained by providing the engagement portion holding means in the cam portion of the cam mechanism without separately providing the engagement state holding means.

According to the third aspect of the present invention, the engagement state can be held by utilizing the reverse drive preventing action of the worm gear mechanism without separately providing the engagement state holding means. The same effect as the invention can be obtained.

According to the fourth aspect of the present invention, when the cam portion is engaged, the flat portions come into contact with each other, and no force for relative movement is generated due to the angle thereof, so that an effect equivalent to the second aspect of the invention is obtained. Can be

According to the fifth aspect of the present invention, when the two cam portions are engaged, the convex portion of the other cam portion is engaged with the concave portion of the one cam portion, thereby maintaining the engagement state. Claim 2
The same effect as that of the invention is obtained.

According to the sixth aspect of the present invention, even if a force in the disengagement direction is generated due to the inclination of the tongues of the two cam portions engaged with each other, the reverse drive preventing action of the worm gear mechanism is utilized. Thus, the same effect as that of the third aspect is obtained.

Further, the cost can be more effectively reduced by a simple configuration in which the tongue portions are formed on both cam portions.

According to the invention described in claim 7, according to claim 2,
And an effect equivalent to that of any one of the inventions is obtained.
Since the plate-like member can be formed by, for example, press molding, the weight can be reduced and the manufacturing cost can be reduced.

According to the invention described in claim 8, claim 1 is provided.
In addition to the effects obtained by the clutch operating mechanism of any one of (1) to (7), the configuration of the differential device is simplified, so that the cost can be reduced.

According to the ninth aspect of the present invention, the first aspect is provided.
7 to 7, the effect can be obtained, and the cost of the transfer device can be reduced because the configuration of the transfer device is not simplified.

According to the tenth aspect, the effect of the clutch operating mechanism according to any one of the first to seventh aspects is obtained, and the configuration of, for example, a parallel shaft type differential device is simplified, and cost reduction is achieved. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a clutch operation mechanism according to a first embodiment of the present invention and a differential device including the same.

FIG. 2 is an enlarged view of a main part of the first embodiment.

FIG. 3 is a cross-sectional view of a clutch operation mechanism and a differential device including the same according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of a clutch operation mechanism according to a second embodiment and a differential device including the same.

FIG. 5 is an enlarged view of a main part of the second embodiment.

FIG. 6 is an enlarged view of a modification of the main part of the second embodiment.

FIG. 7 is an enlarged view of another modification of the main part of the second embodiment.

FIG. 8 is a sectional view of a clutch operating mechanism according to a third embodiment of the present invention and a differential device including the same.

FIG. 9 is an enlarged view of a main part of the third embodiment.

FIG. 10 is an enlarged view of a modification of the main part of the third embodiment.

FIG. 11 is a sectional view of a clutch operating mechanism and a transfer device including the same according to a fourth embodiment of the present invention.

FIG. 12 is a sectional view of a clutch operating mechanism according to a fifth embodiment of the present invention and a differential device including the same.

FIG. 13 is a sectional view of a conventional example.

[Explanation of symbols]

5,373 differential carrier 7,369 differential case 15,391 outer clutch (other clutch member) 17,363 dog clutch (clutch) 25,377a inner clutch (one clutch member) 31 bevel gear differential mechanism 32,387, 389 pinion gear 33 pinion shaft 34 cam mechanism 35, 135, 235, 335, 365 operating mechanism 37 stepping motor (electric motor) 36, 38, 375, 377 side gear 38 drive gear 40 transmission mechanism 41, 141, 241 cam member 41b cam portion 42, 46, 142, 142 ', 146', 142 ",
146 ", 242, 246, 242 ', 246' Cam (holding means) 45, 145, 245 Cam gear 47 Return spring 238 Worm gear mechanism 239 Worm 240 Worm wheel 315 Drive side clutch member 325 Drive side clutch member 355 Chain transmission mechanism (Transmission mechanism)

Claims (10)

[Claims] A cam mechanism for engaging a clutch; an electric motor for driving the cam mechanism via a transmission mechanism to engage the cam mechanism; and holding means for holding the cam mechanism in an engaged state. A clutch operating mechanism comprising: 2. The clutch operating mechanism according to claim 1, wherein said holding means is provided on cam portions which engage with each other when said cam mechanism is engaged. 3. The clutch operating mechanism according to claim 1, wherein said holding means is a worm gear mechanism provided in said transmission mechanism. 4. The clutch operating mechanism according to claim 2, wherein the holding means abuts each other when the cam portion is engaged, and has an angle at which a force in a relative movement direction is not generated after the abutment. A clutch operating mechanism, characterized by being a part. 5. The clutch operating mechanism according to claim 2, wherein said holding means is formed in a cam portion on one side and is formed in a cam portion on the other side and engages with said concave portion when engaged. A clutch operating mechanism comprising a convex portion to be stopped. 6. The clutch operating mechanism according to claim 3, wherein each of the cam portions constituting the cam mechanism has a tongue formed on an inclined surface having substantially the same angle, and both tongues are in the same direction. A clutch operating mechanism characterized in that the clutch operating mechanism is arranged so as to be inclined and opposed to the main body. 7. The clutch operating mechanism according to claim 2, wherein said cam portion is formed of a plate-like member. 8. A bevel gear type differential mechanism housed in a differential case that is rotationally driven by a driving force of an engine; and a one side rotatably housed in the differential case and fixedly supporting a pinion shaft of the differential mechanism. A differential device comprising: a clutch member; and a clutch member on the other side supported so as to rotate integrally with the differential case and movably supported in a rotation axis direction, wherein the two clutch members are engaged. A differential device comprising the clutch operating mechanism according to claim 1. 9. A power transmission system comprising: a first side and a second side output shaft each rotatably supported in a transfer case and connected to each other via a transmission mechanism; A transfer device capable of selectively switching between power transmission to both output shafts on one side and the other side, comprising: a drive side clutch member that rotates integrally with the one side output shaft; and the one side output shaft. A transfer device comprising: a driven clutch member rotatably supported above; and a clutch operating mechanism according to any one of claims 1 to 7, wherein the clutch operation mechanism engages the two clutch members. 10. A differential mechanism comprising a pinion gear and a side gear housed in a differential case rotatably driven by a driving force of an engine; one clutch member provided on a pinion gear or a side gear of the differential mechanism; And a clutch member on the other side that is supported so as to rotate integrally with the other and that is supported so as to be movable in the rotation axis direction, wherein the two clutch members are engaged. A differential device comprising the clutch operation mechanism according to any one of the above.