JP3378100B2 - Clutch structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction clutch,
In particular, the present invention relates to a clutch structure provided with a clutch control mechanism based on reverse torque from the clutch output shaft side.

[0002]

2. Description of the Related Art Conventionally, various examples have been proposed in which a clutch is provided with a reverse torque limiter mechanism for preventing excessive reverse torque from the rear wheels from being transmitted to an engine during a downshift or the like (Japanese Patent Publication No. 5-73928). Japanese Patent Laid-Open No. 59-21
9525, etc.). In these examples, the structure in which the frictional engagement of the clutch is weakened by moving the pressure plate of the friction clutch away from the clutch center when the reverse torque is input.

On the other hand, in a conventional motorcycle having a kick starter mechanism, there is an example in which a kick starting torque is transmitted to a crankshaft via a clutch to be used for starting an engine (Japanese Utility Model Publication No. 61-35807). If the reverse torque limiter mechanism is provided in the same example, the reverse torque limiter mechanism works because the reverse torque limiter mechanism is actuated by the kick starting torque and the torque transmission to the engine is weakened and the engine cannot be smoothly started. The torque limit value must be set high, and the original function of the reverse torque limiter mechanism will be limited.

Therefore, there is an example in which a kick starter mechanism as shown in FIG. 10 is provided. Explaining the outline of the structure of the example, a gear 02 fitted on a crankshaft 01 meshes with a clutch input gear 05 of a clutch outer 04 of a friction clutch 03, and a clutch output shaft 08 integrated with a clutch center 07.
The gear group 09 that is fitted to the counter shaft 011 and the gear group 010 that is fitted to the counter shaft 011 mesh with each other, and the drive of the engine is transmitted from the crank shaft 01 to the counter shaft 011 via the friction clutch 03, and the rotation of the counter shaft 011 is transmitted. Is transmitted to the rear wheels via a chain or the like.

The kick starter mechanism is a dog clutch provided on the pedal shaft 015 on which the kick pedal is fitted.
The idle gear 017, which is rotatably fitted to the counter shaft 011 via the 016, is adapted to rotate. The idle gear 017 meshes with the gear 018 integrated with the clutch input gear 05 of the friction clutch 03. Has become. Therefore, if there is a kick operation, the dog clutch 016
The kick start torque is transmitted to the crankshaft 01 via the idle gear 017, the gear 018, the gear 05, and the gear 02, and is directly transmitted without passing through the friction clutch 03.

As described above, since the kick starting torque is transmitted to the crankshaft 01 without passing through the friction clutch 03, even if the friction clutch 03 is provided with the reverse torque limiter mechanism, the reverse torque is increased to facilitate the kick start. It is not necessary to limit the function of the limiter mechanism, and it is possible to make it possible to sufficiently exert the functions of both the kick start mechanism and the reverse torque limiter mechanism.

[0007]

[Problems to be Solved] However, a so-called push start in which a transmission mechanism via the idle gear 017 is required and the motorcycle is pushed to rotate the rear wheels to start the engine is not smooth. That is, when the counter shaft 011 rotates due to pushing, the same torque transmission path as when reverse torque is input during downshifting is input, and the friction clutch 03 must be passed. The mechanism works to cause slippage in the friction clutch, so that sufficient torque is not transmitted to the crankshaft 01 and the engine cannot be started smoothly. Therefore, both pushing start and reverse torque limiter cannot be achieved at the same time, and neither of them can fully exert their functions.

The present invention has been made in view of the above points,
The purpose thereof is to provide a clutch structure having a simple structure that allows the kick start to be pushed off and the start smooth without restricting the function of the reverse torque limiter mechanism.

[0009]

In order to achieve the above object, the present invention provides a clutch input shaft and a clutch output shaft by expanding and contracting the distance between the clutch center and the pressure plate on the clutch output shaft side. In a friction clutch that connects and disconnects the power transmission between them, a reverse torque limiter mechanism that moves the pressure plate in the direction of increasing the gap with respect to the clutch center by the input of reverse torque, and a centrifugal weight are formed in the clutch center.
The clutch center is provided with a moving restraining member
If the number of revolutions during idling is less than or equal to
For the clutch center of the pressure plate
The clutch structure is provided with a limiter canceling mechanism that restrains the relative displacement in the rotating direction in one direction .

When the rotation speed of the clutch center is equal to or lower than the rotation speed during idling, the limiter cancel mechanism controls the reverse torque limiter mechanism so that it does not operate. Therefore, the reverse torque limiter mechanism is activated at both kick start and push start. If the reverse torque is input during downshifting while driving, the rotation speed of the clutch center exceeds the rotation speed during idling, and the reverse torque limiter mechanism originally It is possible to prevent the engine from over rotating without impairing the function of and to prevent the engine braking from being excessively effective.

The reverse torque limiter mechanism allows the pressure plate to be displaced relative to the clutch center in the rotational direction, and the relative displacement in the rotational direction of the pressure plate with respect to the clutch center due to reverse torque input is determined relative to the rotational axis direction. with converts the displacement enlarging the distance between the clutch center and the pressure plate mechanism, moving the pressure plate in place of the relative displacement in the rotation axis direction of relative displacement in the rotational direction relative to the clutch center in the reverse torque limiter mechanism Without the need for an intermediate member, the limiter canceling mechanism restrains the relative displacement in the rotational direction of the pressure plate with respect to the clutch center when the rotational speed of the clutch center is equal to or lower than the rotational speed during idling. Ki Even when any of the click start or push start start does not work is the reverse torque limiter mechanism can start-up of the smooth engine.

[0012] The limiter cancellation mechanism, the contracture
The bundle member is the clutch plate of the pressure plate.
The relative displacement in the direction of rotation with respect to the
By restraining in one direction , the conversion member does not act on the pressure plate to reduce the starting torque and transmit it to the engine when the rotation speed of the clutch center is equal to or lower than the rotation speed during idling. It can be started.

Further, in the friction clutch for connecting and disconnecting the power transmission between the clutch input shaft and the clutch output shaft by expanding and contracting the distance between the clutch center and the pressure plate on the clutch output shaft side, the input of reverse torque causes A reverse torque limiter mechanism that moves the pressure plate in a direction to increase the gap with respect to the clutch center, and the clutch input shaft and the clutch output shaft can be connected to each other so that they can be connected to and disconnected from each other.
The torque of the clutch output shaft when the rotation speed is less than the ring speed
Is transmitted to the clutch input shaft, but torque is transmitted in the opposite direction.
The clutch structure is equipped with a one-way coupling mechanism that does not work.

When the rotation speed of the clutch center is equal to or lower than the rotation speed during idling, the connecting mechanism connects the clutch input shaft and the clutch output shaft, so that the reverse torque limiter mechanism can be used at both kick start and push start. If the engine can be started smoothly without working and the reverse torque is input during downshifting while driving, etc., the rotational speed of the clutch output shaft exceeds the rotational speed during idling, and the connecting mechanism will When the reverse torque limiter mechanism is released, the reverse torque limiter mechanism works without impairing its original function to prevent the engine from over rotating and prevent the engine braking from being excessively effective. The coupling mechanism is a clutch output
The torque of the force shaft is transmitted to the clutch input shaft, but the opposite direction
It is a one-way coupling mechanism that does not transmit torque in one direction.
Reverse torque limiter mechanism for easy disconnection after engine start
Can make sure it works.

If the connecting mechanism is a ratchet mechanism,
The clutch input shaft and the clutch output shaft are both connected and disconnected by the operation of a centrifugal weight provided on the clutch input shaft side, and the clutch input is input when the rotation speed of the clutch input shaft is equal to or lower than the rotation speed during idling. By connecting the shaft and the clutch output shaft, the clutch input shaft and the clutch output shaft can be connected at the time of kick start or pushing start, and the engine can be smoothly started. The connection of the connecting mechanism is released and the reverse torque limiter mechanism works to prevent the engine from over rotating.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in FIGS. 1 to 7 will be described below. FIG. 1 is a sectional view of a friction clutch 1 of the present embodiment, and FIG. 2 is a sectional view of another section thereof. A cylindrical clutch outer 4 having a bottom is rotatably supported at a predetermined position on a clutch output shaft 2 that is a driven shaft via a bearing 3, and a clutch that is a clutch input shaft is integrally formed along an outer surface of a bottom portion of the clutch outer 4. The input gear 5 is fitted.

The hub 6 is spline-fitted to the clutch output shaft 2 projecting into the cylinder of the clutch outer 4 and is fastened with a nut 7 to inhibit the axial movement of the hub 6 and rotate integrally with the clutch output shaft 2. And the same hub 6
A central cylindrical portion 8a of the clutch center 8 is fitted to the. The clutch center 8 has an annular disc portion 8b extending from the central cylindrical portion 8a in the centrifugal direction, and a flattened cylindrical portion 8c.
To form a flange portion 8d forming an annular disc through
It is fitted and supported by the hub 6 so as to close the opening of the clutch outer 4, and rotates integrally with the clutch output shaft 2.

Inside the clutch outer 4, the pressure plate 9 penetrates inward of the clutch center 8 into the central cylindrical portion 8a of the clutch center 8 so that the pressure plate 9 is supported not only in the axial sliding but also in the relative rotation. ing. The annular plate 9a of the pressure plate 9 has an outer diameter slightly smaller than the inner diameter of the cylinder of the clutch outer 4 and faces the clutch center 8, and the cylindrical portion 9b extending from the middle of the disk 9a has a clutch center 8a. It is formed along the outer peripheral surface of the cylindrical portion 8c.

The cylindrical portion 9b of the pressure plate 9
The clutch friction plate 11 on the clutch outer 8 side and the clutch plate on the pressure plate 9 side are placed in the space between the outer peripheral surface of the clutch outer peripheral surface and the cylindrical inner peripheral surface of the clutch outer 8.
10 and 10 are arranged alternately.

That is, a plurality of split grooves 4a oriented in the axial direction are formed on the inner peripheral surface of the cylinder of the clutch outer 4 in the circumferential direction, and the clutch friction plate is formed in the split grooves 4a.
A plurality of outer peripheral projections 11 are engaged with each other and are axially slidably supported, while a plurality of axially oriented grooves 9c are also provided on the outer peripheral surface of the cylindrical portion 9b of the pressure plate 9. An inner peripheral projection of the clutch plate 10 is engaged with the groove 9c so as to allow axial sliding, and a plurality of sheets are arranged between the clutch friction plates 11 one by one.

The plurality of clutch friction plates 11 and clutch plates 10 are sandwiched between the flange portion 8d of the clutch center 8 and the disc portion 9a of the pressure plate 9. Therefore, the pressure plate 9
When the clutch is closer to the clutch center 8 and the gap is reduced, the clutch friction plate 11 and the clutch plate 10 approach each other to strengthen the frictional engagement, and conversely, when the pressure plate 9 is separated from the clutch center 8 and the gap is increased, the clutch friction is increased. The plate 11 and the clutch plate 10 are separated from each other to weaken the frictional engagement.

The pressure plate 9 is biased in a direction approaching the clutch center 8 (rightward in FIG. 1) by a disc spring 12 which is a clutch spring whose base end is locked to the hub 6.

An annular disc portion 9 of the pressure plate 9
A hollow disc-shaped cam plate 20 is pressed against the surface a of the pressure plate 9 by a disc spring 12 on the surface opposite to the cylindrical portion 9b. A cam recess 20b is provided on the tip end surface of the cam bulge 20a which has three cam bulges 20a which are respectively fitted into the circular holes formed in the hole, and which penetrates the disc 9a of the pressure plate 9.
Are formed.

The disc spring 12 has one end abutting against the cam plate 20 so that the cam plate is pressed against the pressure plate 9 so as to be integrated, and the pressure plate 9 is biased toward the clutch center 8. As shown in FIG. 3, three cam recesses 20b are formed at equal intervals on the surface facing the clutch center 8. As shown in FIG. 4, the cam recesses 20b are formed on the tip end surface of the cam bulge 20a in the rotational direction. It is formed so that the back side is deep and the front side is gradually and shallowly shallow.

Further, as shown in FIG. 3, three screw holes 21 are formed at equal intervals in the annular disc portion 9a of the pressure plate 9, and the periphery of the screw hole 21 is slightly raised to make a release holder described later. The mounting step portion 21a of the support boss 30 is formed. Further, the annular disc portion 9a of the pressure plate 9 is provided with three longitudinal grooves 22 at equal intervals on the surface facing the clutch center 8 as shown in FIGS. 2 and 3, and half of the return spring 35 is formed. It is supposed to fit.

On the other hand, a lifter pin 25 is fitted to the disk portion 8b of the clutch center 8 facing the pressure plate 9 so as to correspond to the cam recess 20, and the head of the lifter pin 25 faces the cam recess 20b. An elongated circular hole 26 is formed in the circumferential direction corresponding to the screw hole 21, and an elongated groove 27 having a semicircular cross section is formed facing the elongated groove 22. A cylindrical release holder support boss 30 which is applied to the mounting step portion 21a of the pressure plate 9 and is projecting by being screwed into the through screw hole 21 by a bolt 31 penetrates the elliptical hole 26 of the clutch center 8. There is.

A release holder 32 provided near the tip of the clutch output shaft 2 has a bearing 33, which is a release operating portion, fitted inside, and a flange of the release holder 32.
An annular ratchet plate 40 is brought into contact with 32a, and the three overlapped portions are brought into contact with the tips of the three release holder supporting bosses 30, respectively, and the bolt 31 releases the release holder supporting boss 30 and the release holder 3
2. The ratchet plate 40 is coaxially penetrated and fastened together to be supported.

The release holder supporting boss 30 penetrating the oval hole 26 of the clutch center 8 is movable along the oval hole 26, so that relative rotation of the pressure plate 9 with respect to the clutch center 8 results in release holder supporting boss.
The stopper mechanism is constructed by restricting 30 within the range in which the elliptical hole 26 can move.

A return spring 35 is provided in the long groove 22 on the pressure plate 9 side and the long groove 27 on the clutch center 8 side so as to be contracted in the circumferential direction.
When the clutch center 8 advances in the rotation direction relative to the pressure plate 9, the clutch center 8 is urged to return it.

As shown in FIG. 5, the ratchet plate 40 has a receiving portion that bulges rearward in the rotational direction (arrow direction) with a groove between the engaging projection 40b and a groove at the periphery between the mounting portions 40a and 40a by the bolt 31. 40c is formed.

On the other hand, a flat cylindrical boss portion 8e is formed on the flange portion 8d of the clutch center 8 at a position substantially corresponding to the locking projection 40b and the receiving portion 40c of the ratchet plate 40, and the bearing 41 is mounted on the cylindrical boss portion 8e. A kick weight 42 is pivotally supported at its base end via a washer 43 and a flat screw.
It is swingably attached by 44 (see Fig. 1).

As shown in FIG. 5, the kick weight 42 has a weight arm 42a and a locking arm 42b extending from the base end in the direction of rotation, and the weight arm 42a is located at a more centrifugal position than the locking arm 42b. It is long. In the kick weight 42, the weight arm 42a and the locking arm 42b are biased toward the central axis, that is, the ratchet plate 40 side by a set spring 45 interposed between the kick weight 42 and the clutch center 8.

Since the locking arm 42b is at the same position in the axial direction as the ratchet plate 40, it is in contact with the ratchet plate 40 by the spring force of the set spring 45 when it is stopped. Also the clutch center 8
A stopper 46 is provided at a predetermined position on the outer peripheral edge of the flange portion 8d.
Is provided (see FIG. 5), the tip end of the weight arm 42a of the kick weight 42 comes into contact with the kick weight 42.
It is designed to regulate the swing of.

A limit canceling mechanism is constituted by a combination of the kick weight 42 and the ratchet plate 40, etc., and when the clutch center 8 together with the clutch output shaft 2 is stopped or the idling speed is equal to or lower than a predetermined rotation speed, the kick weight is set. 42 is a set spring 45
When the ratchet plate 40 is pushed toward the ratchet plate 40 side by the clutch center 8 and is most advanced in the rotational direction from the clutch center 8, as shown by the solid line in FIG.
Is in contact with the receiving portion 40c and the tip of the locking arm 42b is in contact with and engages with the locking projection 40b, and restrains the relative rotation of the ratchet plate 40 with respect to the clutch center 8.

The ratchet plate 40 is a release holder
32, the pressure plate 9 is integrated with the release holder support boss 30. Therefore, in the above state, the pressure plate 9 is prohibited from rotating relative to the clutch center 8 and the pressure plate 9 is closest to the clutch center 8. Therefore, the clutch engagement state is maintained, and therefore the torque reversely input from the clutch output shaft 2 is transmitted to the clutch input gear 5 via the friction clutch 1 in the connected state without causing slippage on the way.

Therefore, in kick starting, the rotational torque of the clutch output shaft 2 which rotates at the time of pushing and starting is transmitted to the clutch input gear 5 with a slight power loss, and transmitted from the clutch input gear 5 to the crankshaft of the engine. Can be smoothly started.

Then, when the clutch center 8 reaches a rotational speed above a predetermined idling rotational speed, the set spring
45 cannot withstand the outward swing of the kick weight 42 due to centrifugal force, and as shown by the chain double-dashed line in FIG.
Swings to release the engagement of the locking arm 42b with the locking projection 40b of the ratchet plate 40, so that the relative rotation between the clutch center 8 and the pressure plate 9 is free.

3 and 6 show the pressure plate 9
FIG. 6 is a front view of the clutch center 8 as viewed from the side of the clutch center 8 side.
6, the relative position of the long groove 27 is shown by a chain double-dashed line, FIG. 3 shows a state during normal running or acceleration, and FIG. 6 shows a state during deceleration.

During normal running, the clutch center 8 on the driven side is delayed as compared with the driving side, and the biasing force of the return spring 35 also acts on the front end of the oval hole 26 on the clutch center 8 side in the rotational direction as shown in FIG. The mounting step portion 21a (release holder support boss 30) is positioned in advance to rotate the clutch center 8 integrally, and the lifter pin 25 is also delayed and located at the deepest recess on the rear side in the rotational direction of the cam recess 20. (See Figure 4).

Therefore, the pressure plate 9 is located closest to the clutch center 8, and the distance between the flange portion 8d of the clutch center 8 and the disc portion 9a of the pressure plate 9 is reduced to reduce the clutch friction plate 11 and the clutch plate. The frictional engagement with 10 is strengthened to bring the clutch into the engaged state, and the drive of the clutch input gear 5 is transmitted to the clutch output shaft 2 with a slight power loss.

During deceleration or until the vehicle stops, reverse torque is applied to the clutch by the engine brake, and the clutch center 8 integrated with the clutch output shaft 2 which is the driven shaft rotates in the direction of rotation from the pressure plate 9 on the engine side. As shown in FIG. 6, the elliptical hole 26 on the clutch center 8 side advances relative to the mounting step portion 21a (release holder supporting boss 30) on the pressure plate 9 side against the return spring 35 as shown in FIG. The lifter pin 25 moves relatively to the front side of the cam concave portion 20 in the rotational direction, and as shown in FIG. 7, the depression becomes gradually shallower to press the pressure plate 9 in the axial direction to generate a load against the disc spring 12. .

Therefore, the distance between the flange portion 8d of the clutch center 8 and the disc portion 9a of the pressure plate 9 can be increased to weaken the frictional engagement between the clutch friction plate 11 and the clutch plate 10 so that the clutch can slide properly. Therefore, it is possible to prevent excessive reverse torque from acting on the clutch input gear 5 and being applied to the engine side, and prevent excessive rotation. On the contrary, it is possible to prevent the engine braking from being excessively effective.

As described above, when the engine is rotating at a predetermined idling speed or more, the engagement between the kick weight 42 and the ratchet plate 40 is released, and the relative rotation between the clutch center 8 and the pressure plate 9 is free. The reverse torque limiter mechanism works to prevent the engine from over-rotating and the engine braking from being too effective.

When the clutch lever is operated to disengage the clutch, the release holder 32 is pushed toward the clutch output shaft 2 side by interlocking with the clutch lever, and the pressure plate 9 is passed through the release holder support boss 30 and the disc spring 12 is pressed.
By moving the clutch center 8 away from the clutch center 8, the frictional engagement between the clutch friction plate 11 and the clutch plate 10 can be released and the clutch can be disengaged. At this time, even if the ratchet plate 40 and the kick weight 42 are engaged, relative movement in the axial direction is free.
In the structure of the present embodiment, the reverse torque of the clutch output shaft 2 can start the engine, so it is not necessary to provide an idle gear for torque transmission for kick start.

Next, another embodiment will be described with reference to FIGS. In the friction clutch 50 of this embodiment, the structure of the clutch body and the reverse torque limiter mechanism are the same as those in the above embodiment, and the same members are designated by the same reference numerals. A cam plate 51 corresponding to the cam plate 20 is provided on the outer peripheral edge of the disc with a ratchet ring 51a.
The ratchet ring 51a is formed with ratchet teeth on the inner peripheral surface as shown in FIG.

On the other hand, a flat cylindrical boss portion 52a is formed on the disc portion of the clutch outer 52 facing the disc portion of the cam plate 51, and a kick weight 54 is pivotally supported on the cylindrical boss portion 52a via a bearing 53. It is swingably attached by bolts 55 and nuts 56. The kick weight 54 has a long weight arm 54a extending in the rotation direction (arrow direction) from the pivot and a short locking arm 54b extending in the opposite direction, and the locking arm 54b can be engaged with the ratchet ring 51a. Is. Stopper is in place on the disc of clutch outer 52
52b is projected (see FIG. 9) and kick weight 54
Rocking is regulated.

This kick weight 54 is a clutch outer
As shown in FIG.
In the case where the ratchet ring 51a is biased counterclockwise in FIG.
Engaged with the teeth of. However, the engagement of the locking arm 54b with the ratchet ring 51a is one-way coupling, and the clutch outer 52, that is, the kick weight 54 is in the same direction with respect to the reverse torque rotation of the clutch output shaft 2, that is, the rotation of the ratchet ring 51a in the arrow direction. Although the relative rotation is free, the relative reverse rotation is prohibited by the engagement of the locking arm 54b with the ratchet ring 51a.

Therefore, when the clutch outer 52 is stopped or when the idling speed is equal to or lower than a predetermined speed,
The kick weight 54 is pressed to the ratchet ring 51a side by the set spring 57, and as shown by the solid line in FIG. 9, the locking arm 54b is engaged with the ratchet ring 51a in one direction, but the kick start is pushed from the beginning. The rotation torque of the clutch output shaft 2 that rotates at the time of start is transmitted to the clutch input gear 5 via the ratchet ring 51a of the cam plate 51 and the kick weight 54 that are integral with the pressure plate 9, and then from the clutch input gear 5 to the crankshaft of the engine. Thus, the engine can be smoothly started.

After the engine is started, since the kick weight 54 rotates ahead of the ratchet ring 51a, the locking arm 54b oscillates by tracing the peaks and valleys of the teeth of the ratchet ring 51a in sequence, so that the clutch outer 52 idles. The kick weight 54 can be reliably swung and disengaged by the centrifugal force applied to the weight arm 54a beyond a predetermined number of rotations, and the locking arm 54b is temporarily coupled to the teeth of the ratchet ring 51a and cannot be disengaged. It is possible to prevent the occurrence of defects.

As described above, when the clutch outer 52 reaches the idling speed of a predetermined speed or more, the set spring 57 cannot withstand the outward swing of the weight arm 54a due to the centrifugal force, as shown by a chain double-dashed line in FIG. Since the kick weight 54 swings and disengages from the teeth of the ratchet ring 51 of the locking arm 54b, the direct transmission of torque between the pressure plate 9 and the clutch outer 52 is cut off and independent from each other. The limiter mechanism can function freely.

That is, similarly to the above-described embodiment, the clutch outer 52 is decelerated during deceleration or until the vehicle stops.
Is in the disengaged state by the kick weight 54 at a predetermined idling speed or more, reverse torque is applied to the clutch by the engine brake, and the clutch center 8 integrated with the clutch output shaft 2 that is the driven shaft is located on the engine side. By engaging the lifter pin 25 and the cam recess 20 ahead of the pressure plate 9 in the rotational direction, the pressure plate 9 is engaged.
Is pressed in the axial direction and the flange portion 8 of the clutch center 8 is pressed.
The distance with d can be enlarged to weaken the frictional engagement and slip the clutch appropriately, and excessive reverse torque acts on the clutch input gear 5 to reduce the influence on the engine side to prevent over-rotation. It is possible to prevent excessive braking.

Therefore, also in this embodiment, both the reverse torque limiter mechanism and the limit cancel mechanism can be compatible with each other, and both can exhibit sufficient functions.

[0053]

According to the present invention, the limiter cancel mechanism controls the reverse torque limiter mechanism so that the reverse torque limiter mechanism does not operate when the number of revolutions of the clutch center is equal to or less than the number of revolutions during idling, so that either kick start or push start is performed. Even when the reverse torque limiter mechanism does not work and the engine can be started smoothly, on the other hand, when reverse torque is input during downshifting etc. while traveling, the rotation speed of the clutch center exceeds the rotation speed at idling, The reverse torque limiter mechanism works without impairing the original function to prevent the engine from over-rotating and prevent the engine braking from being overly effective.

Further, when the rotation speed of the clutch center is equal to or lower than the rotation speed during idling, the connecting mechanism connects the clutch input shaft and the clutch output shaft, so that the reverse torque limiter can be used at both kick start and push start. If the mechanism does not work and the engine can be started smoothly, and if reverse torque is input during downshifting while driving, etc., the number of rotations of the clutch output shaft exceeds the number of rotations during idling, and the connection mechanism is connected. By being released, the reverse torque limiter mechanism works without impairing its original function to prevent the engine from over-rotating and prevent the engine braking from being overly effective.

[Brief description of drawings]

FIG. 1 is a sectional view of a friction clutch according to an embodiment of the present invention.

FIG. 2 is a partially omitted cross-sectional view of another cut surface of the friction clutch.

FIG. 3 is a front view of the pressure plate of the same embodiment.

4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a front view of a main part showing a limiter canceling mechanism.

FIG. 6 is a front view of the pressure plate in another state.

7 is a sectional view taken along line VII-VII in FIG.

FIG. 8 is a sectional view of a friction clutch according to another embodiment.

FIG. 9 is a partially omitted front view showing a limiter canceling mechanism in the embodiment.

FIG. 10 is a cross-sectional view showing a conventional drive transmission mechanism.

[Explanation of symbols]

1 ... Friction clutch, 2 ... Clutch output shaft, 3 ... Bearing, 4
... clutch outer, 5 ... clutch input gear, 6 ... hub, 7 ... nut, 8 ... clutch center, 9 ... pressure plate, 10 ... clutch plate, 11 ... clutch friction plate, 12 ... disc spring, 20 ... cam recess, 21 …
Screw hole, 22 ... Oval groove, 25 ... Lifter pin, 26 ... Oval hole, 27
… Long groove, 30… Release holder support boss, 31… Bolt,
32 ... Release holder, 33 ... Bearing, 35 ... Return spring, 40 ... Ratchet plate, 41 ... Bearing, 42 ... Kick weight, 43 ... Washer, 44 ... Flat screw, 45 ... Set spring, 50 ... Friction clutch, 51 ... Cam Plate, 52 ... Clutch outer, 53 ... Bearing, 54 ... Kick weight, 55 ... Bolt, 56 ... Nut, 57 ... Set spring.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 62-72927 (JP, A) Fukuihei 3-49430 (JP, U) Fukuikaihei 2-66736 (JP, U) Japanese Patent Publication 5- 73928 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16D 11/00-23/14 F16D 43/21 F16D 47/04

Claims (5)

(57) [Claims] 1. A friction clutch in which a clutch center on the clutch output shaft side and a pressure plate expand and contract the distance between them to connect and disconnect power transmission between the clutch input shaft and the clutch output shaft. A reverse torque limiter mechanism that moves the pressure plate in a direction to increase the distance from the clutch center by the, and a restraint portion that operates on the clutch center with a centrifugal weight.
The clutch center is idling
When the rotation speed is less than
The rotation direction of the plate with respect to the clutch center
A clutch structure including a limiter canceling mechanism that restrains relative displacement in one direction . 2. The reverse torque limiter mechanism enables relative displacement of the pressure plate in the rotational direction with respect to the clutch center, and the relative displacement in the rotational direction of the pressure plate with respect to the clutch center due to reverse torque input is in the rotational axis direction. clutch structure according to claim 1, wherein converting the relative displacement, characterized in that a mechanism to extend the distance between the clutch center and the pressure plate. 3. The limiter canceling mechanism comprises:
The restraint member is the clutch plate of the pressure plate.
To the ratchet mechanism
The binding is further restricted in one direction.
Alternatively, the clutch structure according to claim 2. 4. A friction clutch for connecting and disconnecting power transmission between a clutch input shaft and a clutch output shaft by expanding and contracting a distance between a clutch center and a pressure plate on the clutch output shaft side, in which a reverse torque is input. A reverse torque limiter mechanism that moves the pressure plate in a direction to increase the distance from the clutch center by the clutch input shaft and the clutch output shaft can be connected to each other so that the clutch output shaft can rotate.
If the rotational speed is less than the
The torque is transmitted to the input shaft, but torque is transmitted in the opposite direction.
A clutch structure having a one-way coupling mechanism that does not break . 5. The connecting mechanism forms a ratchet mechanism.
Clutch structure according to claim 4, characterized in that the disengaging of the clutch output shaft and the clutch input shaft by the operation of the centrifugal weights provided in the clutch input shaft side with.