JPH10292831A - Centrifugal clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce torque shock at the time of a gear shift and miniaturize a centrifugal mechanism by driving a driving frictional element and a centrifugal mechanism by an input member at each different speed ratio. SOLUTION: A crankshaft 2 drives a clutch outer 10 of a clutch mechanism 9 and a cam plate 31 of a centrifugal mechanism 29 by starting an engine. The clutch mechanism 9 is driven, driven frictional plates 12, 13 are free and a clutch interruption state is made because the number of revolution of the cam plate 31 is low and centrifugal force of a centrigual weight 32 is weak at the time of an idling. When a switch from a neutral location to a low location of a transmission is performed, a shock imparted to a layshaft is slight because the rotational inertia force is weak, even if a main shaft 3 system is rapidly stopped by the layshaft. The clutch is driven by a rise of the engine speed of the engine, clutch engagement force between the driven frictional plates 12, 13 is increased and the clutch mechanism 9 is smoothly transferred to a connection state. The cam plate 31 can be revolved at high speed by the clutch mechanism 9, the centrifugal weight 32 is made light in weight and the centrifugal mechanism 29 can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal clutch, and more particularly, to a clutch mechanism having a driving friction element connected to an input member and a driven friction element connected to an output member, and responding to an increase in the rotation speed of the input member. A centrifugal mechanism for increasing the clutch engagement force by bringing the driving friction element and the driven friction element into pressure contact with each other.

[0002]

2. Description of the Related Art Conventionally, as such a centrifugal clutch, a clutch mechanism and a centrifugal mechanism are provided on a drive shaft of a prime mover, and both a driving friction element and a centrifugal mechanism are directly driven by the drive shaft. No. 60-26825).

[0003] A clutch mechanism and a centrifugal mechanism are provided on a main shaft of a transmission arranged in parallel with a drive shaft of a prime mover, and both the driving friction element and the centrifugal mechanism are decelerated by the drive shaft of the prime mover ( JP-A-56-52629). It has been known.

[0004]

In the above-described configuration, even when the engine is idling when the centrifugal mechanism is not operating,
In the clutch mechanism, the driven friction element also rotates by being dragged by the driving friction element due to the viscosity of the lubricating oil.
Since the driving friction element is driven at a relatively high rotation speed by the driving shaft of the prime mover, the rotational inertia force of the driven friction element system is relatively large. For this reason, when the transmission is switched from the neutral position to the low position, the influence of torque shock on the sub shaft due to the inertial rotation of the driven friction element system appears greatly, and the ride comfort is impaired.

In the above arrangement, since the driving friction element of the clutch mechanism is decelerated from the drive shaft of the prime mover, the torque shock at the time of shifting as in the former is small. The centrifugal mechanism is also decelerated from the drive shaft of the prime mover. Therefore, in order to apply a sufficient centrifugal force to the centrifugal mechanism in a predetermined rotation range of the prime mover, it is necessary to increase the weight and the radius of gyration of the centrifugal weight of the centrifugal mechanism. It is not preferable because it causes an increase in size.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and has solved all of the above disadvantages by enabling the clutch mechanism and the centrifugal mechanism to be driven at a rotational speed suitable for each function. It is an object of the present invention to provide the centrifugal clutch.

[0007]

In order to achieve the above object, the present invention provides a clutch mechanism having a driving friction element connected to an input member and a driven friction element connected to an output member.
A centrifugal clutch comprising: a centrifugal mechanism that increases the clutch engagement force by pressing the driving friction element and the driven friction element against each other in response to an increase in the rotation speed of the input member. The first feature is that the motors are driven at different speed ratios.

[0008] According to the first feature, the clutch mechanism and the centrifugal mechanism can be given rotation speeds adapted to their respective functions, and the degree of freedom in designing the clutch mechanism and the centrifugal mechanism is increased.

In addition, the present invention is characterized in that, in addition to the above features, a speed ratio between the input member and the centrifugal mechanism is set to be larger than a speed ratio between the input member and the driving friction element.

According to the second feature, the rotational speed of the clutch mechanism can be kept relatively low, the torque shock at the time of shifting due to the inertial rotation of the driven friction element system can be reduced, and the centrifugal mechanism has a relatively high speed. A desired centrifugal thrust can be applied to the clutch mechanism by increasing the number of rotations to reduce its weight and size.

Further, in addition to the above-mentioned second feature, the present invention further provides a driving friction element rotatably provided on a main shaft of a transmission as an output member, the driving friction element being decelerated and driven from a driving shaft of a prime mover as an input member. And a centrifugal mechanism that is driven from the drive shaft at the same speed as the main shaft is provided as a third feature.

According to the third feature, the rotational speed of the clutch mechanism is suppressed to be lower than that of the prime mover, and the torque shock at the time of gear shifting due to the inertial rotation of the driven friction element system can be reliably mitigated. In this case, the same number of rotations as that of the prime mover can be given to reduce the size of the engine, and a desired centrifugal thrust can be given to the clutch mechanism.

Still further, in addition to the third feature, the present invention further provides a clutch outer rotatably supported by the main shaft and driven from the drive shaft via a reduction gear train, and a clutch outer of the clutch outer. A plurality of drive friction elements slidably fitted around the circumference; and a plurality of drive friction elements slidably fitted slidably around the outer periphery of a clutch inner connected to the main shaft and arranged alternately adjacent to the drive friction elements. A cam plate which is rotatably supported by the main shaft and driven from the drive shaft via the same speed gear train, and is disposed so as to be able to approach and separate from the cam plate. A thrust plate, a centrifugal weight interposed between the cam plate and the thrust plate, which applies thrust to the thrust plate by moving outward in the radial direction as the centrifugal force increases, and a thrust force generated by the thrust plate. mechanism A fourth, characterized in that to constitute a centrifugal mechanism and thrust transmitting means for transmitting as a clutch engagement force.

According to the fourth feature, the centrifugal thrust of the centrifugal weight can be accurately given to the clutch mechanism as the clutch engagement force regardless of the rotational speed difference between the clutch mechanism and the centrifugal mechanism.

Further, the present invention provides a clutch mechanism having a driving friction element connected to an input member and a driven friction element connected to an output member, and the driving friction element and the driven friction element in response to an increase in the rotation speed of the input member. A fifth feature is that the centrifugal clutch includes a centrifugal mechanism that presses each other to increase the clutch engagement force, wherein the clutch mechanism and the centrifugal mechanism are connected to each other so as to be relatively rotatable.

According to the fifth feature, the clutch mechanism and the centrifugal mechanism can be provided with a rotational speed suitable for each function without difficulty, thereby increasing the degree of freedom in designing the clutch mechanism and the centrifugal mechanism. be able to.

Further, in the present invention, in addition to the fifth feature, a sixth feature is that a clutch mechanism and a centrifugal mechanism are coaxially disposed adjacent to each other.

According to the sixth feature, the centrifugal clutch including the clutch mechanism and the centrifugal mechanism can be made compact.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on embodiments of the present invention shown in the accompanying drawings.

First, the first embodiment of the present invention shown in FIGS.
An example will be described. In FIG. 1, a power unit P for a motorcycle includes an engine E as a prime mover and a transmission T, and a crankcase and a transmission case are integrally formed as a common casing 1.

In the casing 1, a crankshaft 2 (input member) of the engine E, and a main shaft 3 (output member) and a sub shaft 4 of the transmission T are disposed in parallel with each other, and are driven by the crankshaft 2. The centrifugal clutch 5 of the present invention is mounted on the main shaft 3. The centrifugal clutch 5 is configured as a so-called wet type in which lubricating oil of the engine E is supplied for cooling the centrifugal clutch 5.

A plurality of transmission gear trains 6 _{1 to} 6 n are provided between the main shaft 3 and the sub shaft 4. When the centrifugal clutch 5 is connected, the power transmitted from the crankshaft 2 to the main shaft 3 is selected. The transmission is transmitted to the countershaft 4 via two transmission gear trains and to the rear wheel of a motorcycle (not shown) via a chain transmission 7.

As shown in FIG. 2, the clutch mechanism 9 of the centrifugal clutch 5 includes a clutch outer 10 disposed concentrically on the main shaft 3, a clutch inner 11 disposed concentrically within the clutch outer 10, and a clutch. A large number of driving friction plates 12 slidably fitted to the inner periphery of the outer 10
(Driving friction elements), which are spline-fitted slidably on the outer periphery of the clutch inner 11 and have a large number of driving friction plates 1.
2, a plurality of driven friction plates 13 (driven friction elements), a sliding plate 14 slidably and spline-fitted on the inner periphery thereof to support the clutch inner 11, and a reverse of the sliding plate 14. An output ring 16 is connected via a load transmitting cam mechanism 15 and spline-coupled to the main shaft 3. The output ring 16 is fixed to the main shaft 3 by a nut 17.

Between the crankshaft 2 and the main shaft 3, a reduction gear train 18 composed of a small-diameter drive gear 18a fixed to the crankshaft 2 and a large-diameter driven gear 18b rotatably supported on the main shaft 3 is provided. An end wall 10 a of the clutch outer 10 is connected to one side surface of the driven gear 18 b via a rubber damper 19.

The clutch inner 11 is formed integrally with a pressure plate 20 which faces one side of a group of driven and driven friction plates 12 and 13 on the end wall 10a side of the clutch outer 10. A pressure receiving plate 21 that is spline-coupled to the clutch inner 11 while being prevented from moving outward in the axial direction by a retaining ring 24 on the main shaft 3 faces the other side of the drive and driven friction plates 12 and 13. Placed. On one side surface of the clutch inner 11, a plurality of bosses 22 (only one of which is shown in the figure) penetrating the pressure receiving plate 21 loosely in the axial direction are protrudingly provided. Pressure plate 2
A return spring 23 contracted between the two is mounted, and the return spring 23 acts to separate the pressure plate 20 and the pressure receiving plate 21 from each other.

The clutch inner 11 has a sliding plate 1
A stop ring 27 for restricting the relative movement of the lock member 4 toward the end wall 10a is attached. On the opposite side of the stop ring 27, a clutch spring 28 composed of a plurality of disc springs is provided between the clutch inner 11 and the sliding plate 14. Is installed. This clutch spring 28
Is set to have a larger spring constant than that of the return spring 23, but is usually placed in a no-load state.

The cam mechanism 15, as shown in FIG.
A plurality of protrusions 25 protruding from the outer peripheral surface of the output ring 16
And a plurality of axial grooves 26 provided on the inner peripheral surface of the clutch inner 11 to receive the projections 25 respectively. One end of the axial groove 26 is connected to the clutch inner 11.
The closed end face and the projection 25 facing the closed end face are formed on slopes 25a and 26a slidably in contact with each other. Is rotated in the clutch rotation direction R with respect to the clutch inner 11, a thrust F for the clutch inner 11 to press the clutch spring 28 is generated by the relative sliding of the slopes 25a and 26a.

Referring again to FIG. 2, a centrifugal mechanism 29 of the centrifugal clutch 5 is provided on the main shaft 3 adjacent to the clutch mechanism 9 with the reduction gear train 18 interposed therebetween. A drive gear 30 fixed to the crankshaft 2 is provided between the crankshaft 2 and the main shaft 3.
a, and a driven gear 30b having the same diameter as the driven gear 30b rotatably supported on the main shaft 3. A cam plate 31 of the centrifugal mechanism 29 is riveted to one side surface of the driven gear 30b. Is done. Further, the bosses 30b ₁ of the driven gear 30b, the thrust plate 33 facing the cam plate 31 is slidably supported, a plurality of ball-shaped or roller-shaped centrifugal weight 32 between their facing surfaces is annular A guide wall 3 provided to guide the radial movement of these centrifugal weights 32
1 a is provided on the cam plate 31. When the centrifugal weight 32 moves outward in the radial direction along the guide wall 31a and climbs the slope of the cam plate 31, a thrust to the clutch mechanism 9 is applied to the thrust plate 33. Such a centrifugal weight 3
An annular stopper wall 31 b is provided on the outer periphery of the cam plate 31 so as to constantly restrict the outward movement of the cam plate 31. The thrust plate 33 is provided with a pressing ring 3 via a ball bearing 39.
4 are rotatably connected to each other, and the other end of a plurality of rods 35 that abut one end of the pressing ring 34 and penetrate the driven gear 30b and the end wall 10a is connected to the thrust bearing 3.
6 and comes into contact with the side surface of the sliding plate 14.

[0029] Each rod 35, the slidably supported in the through hole 37 ₁ of the driven gear 30b, through holes 37 _{and second} end walls 10a of the rod 35 penetrates, said rod 35 in the operation of the rubber damper 19 The driven gear 30b and the end wall 10a are formed to have a sufficiently large diameter or a long hole so as not to hinder relative displacement at a constant angle. The bearing 39 and the pressing ring 3
4, the rod 35 and the thrust bearing 36 are provided with thrust transmitting means 38 for applying the thrust of the thrust plate 33 to the clutch mechanism 9.
Is configured.

The clutch mechanism 9 is provided with a forcible shutoff mechanism 40 for forcibly interrupting the clutch. The forcible shut-off mechanism 40 includes a release cam plate 43 that is relatively rotatably connected to an end plate 41 fixed to an outer end of the boss 22 of the clutch inner 11 via a release bearing 42,
A roller support 45 that supports a roller 44 cooperating with the release cam plate 43 is screwed into an adjustment bolt 46 provided on the casing 1 and supported by the casing 1 so as to be movable only in the axial direction. The adjusting bolt 46 is usually fixed to the casing 1 by a nut 47. The release cam plate 43 is provided with a long hole 48 extending in the radial direction, and the tip of a clutch lever 49 interlocked with a change pedal (not shown) is engaged with the long hole 48.

When the release cam plate 43 is rotated by the clutch lever 49, the cam surface thereof is
The release cam plate 43 presses the end plate 41 via the release bearing 42 by the reaction, and the pressure plate 20 can be separated from the pressure receiving plate 21. Also,
By loosening the nut 47 and rotating the adjustment bolt 46 appropriately, the position of the roller 44, that is, the release cam plate 4
3, the effective operation start timing can be adjusted.

Next, the operation of this embodiment will be described.

When the engine E is started, the crankshaft 2
Are connected to the clutch outer 10 of the clutch mechanism 9 via the reduction gear train 18 and the centrifugal mechanism 2 via the same speed gear train 30.
9 are driven. However, when the engine E is idling, the rotation speed of the cam plate 31 is relatively low, and the centrifugal force of the centrifugal weight 32 is relatively weak. In the mechanism 9, the pressure plate 20 and the pressure receiving plate 21 are separated by the return spring 23, the drive and driven friction plates 12, 13 are free, and the clutch is disconnected.

However, in the neutral state of the transmission T, the main shaft 3 is placed in a no-load state, so that the main shaft 3 rotates together with the clutch outer 10 due to the viscosity of lubricating oil interposed between the driven and driven friction plates 12, 13. Drive friction plate 1
2, the driven friction plate 13 and the main shaft 3 connected to the driven friction plate also rotate. However, since the clutch outer 10 is driven from the crankshaft 2 via the reduction gear 18, the rotational speeds thereof are relatively low. . For this reason, the transmission T
Is switched from the neutral position to the low position, even if the rotation of the main shaft 3 is suddenly stopped by the sub-shaft 4 connected to the load, the torque shock applied to the sub-shaft 4 Relatively minor.

When the rotation speed of the engine E is gradually increased after shifting to the low position, the rotation speed of the cam plate 31 of the centrifugal mechanism 29 also increases in proportion thereto, and the centrifugal force of the centrifugal weight 32 increases. Accordingly, the thrust exerted on the thrust plate 33 also increases, and the thrust presses the sliding plate 14 of the clutch mechanism 9 via the pressing ring 34 and the rod 35 to apply a load to the clutch spring 28. The clutch inner 11, that is, the pressure plate 20 is urged against the pressure receiving plate 21 by the load of the clutch spring 28, and the driving and driven friction plates 12, 1 are provided between the two plates 20, 21.
The third group is being pinched. As a result, the clutch engagement force between the driving and driven friction plates 12 and 13 increases in accordance with the increase in the rotation speed of the engine E, and the clutch mechanism 9 smoothly shifts to the connected state through the half-clutch state, and the crankshaft 2 is driven by the clutch outer 10 and driven by the driven friction plate 1.
2,13, the clutch inner 11 is transmitted to the main shaft 3 successively through the sliding plate 14 and the output ring 16 is further transmitted through the low gear train ₆₁ to the counter shaft 4, starting is carried out.

By the way, the cam plate 31 of the centrifugal mechanism 29
From the crankshaft 2 via the same speed gear train 30
Is driven at the same rotation speed as that of the clutch mechanism 9 driven through the reduction gear train 18, so that the rotation can always be performed at a higher rotation speed. Therefore, the weight of the centrifugal weight 32 or the centrifugal weight is reduced. By downsizing the centrifugal mechanism 29 by shortening the radius of rotation of 32, a sufficient centrifugal force for connecting the clutch mechanism 9 can be obtained.

After the rotation speed of the engine E reaches a predetermined high rotation speed, the movement of the centrifugal weight 32 outward in the radial direction is restricted by the stopper wall 31 b of the cam plate 31. The increase in the load applied to the clutch spring 28 is also regulated to a constant value, and unnecessary increase in the clutch engagement force is suppressed.

When the forcible shut-off mechanism 40 is operated as described above in such a clutch connection state, the release cam plate 43 is connected to the end plate 41 via the release bearing 42.
Is pressed to separate the clutch inner 11, that is, the pressure plate 20, from the pressure receiving plate 21 while bending the clutch spring 28,
A clutch disengaged state can be obtained. Therefore, it is possible to subsequently switch the transmission T further.

At the time of engine braking, the reverse load applied to the countershaft 4 causes the cam mechanism 15 between the output ring 16 and the sliding plate 14 to operate from the state shown in FIG. Applies a load to the clutch spring 28, so that the connected state of the clutch can be maintained, and good engine braking can be obtained. Such an operation also means that, when the main shaft 3 is driven by a kick operation, the clutch E is obtained by engaging the clutch, cranking the engine E, and enabling the engine E to start.

Next, referring to FIGS. 4 and 5, the second embodiment of the present invention will be described.
An example will be described.

The second embodiment differs from the first embodiment in the clutch mechanism 9 and the forcible shutoff mechanism 40.

That is, in the clutch mechanism 9, the clutch inner 11 is slidably fitted to an output ring 16 fixed to the main shaft 3, and a cam mechanism 15 for transmitting a reverse load is formed therebetween. . The pressure receiving plate 21 slidably supported by the output ring 16 is restricted from moving toward the pressure plate 20 by a retaining ring 50 on the output ring 16. The flange 51 formed at the end of the output ring 16 on the opposite side to the pressure receiving plate 21
And a clutch spring 28 is interposed therebetween.

When the centrifugal mechanism 29 is operated, the thrust plate 33 is moved by the centrifugal force of the centrifugal weight 32 via the bearing 39, the rod 35 and the thrust bearing 36.
Is pressed, the thrust is generated by the driving and driven friction plates 12, 1
The third group and the pressure receiving plate 21 are pressed against the clutch spring 28, and the load applied to the spring 28 is the clamping force between the pressure plate 20 and the pressure receiving plate 21. Therefore, the centrifugal weight 3
The clutch connection state corresponding to the centrifugal force of No. 2 is obtained.

On the other hand, the forcible shut-off mechanism 40 has an end plate 54 fitted into a concave portion 52 opened on the outer surface of the pressure receiving plate 21 and locked by a retaining ring 53, and a release bearing at the center of the end plate 54. A release member 55 which is connected to the release member 55 through the main shaft 3 and which is slidably fitted to the inner peripheral surface of one end of the hollow main shaft 3; Push rod 56 projecting outside 3
A cam piston 57 which is in contact with the other end of the push rod 56;
And a retainer 6 which is screwed to an adjusting bolt 59 attached to an end wall of the cylinder 58 to face the cam surface of the cam piston 57.
2 and the cam piston 57 supported by the retainer 62.
And a ball 61 that engages with the cam surface. A rotating plate 65 is fixed to the outer end of the cam piston 57. The adjusting bolt 59 is fixed to an end wall of the cylinder 58 by a nut 60, and the retainer 62 is slidably engaged with a key-shaped projection 63 protruding from the inner surface of the cylinder 58.

When the rotating plate 65 is rotated by a clutch lever (not shown), the cam piston 57 is also rotated together with the rotating plate 65, and the cam surface presses the ball 61, and the reaction is caused by the reaction. The cam piston 57 moves forward to press the push rod 56 and separate the pressure receiving plate 21 from the pressure plate 20 via the release member 55, the release bearing 42, and the end plate 54, so that the clutch can be disconnected.

Further, the nut 60 is loosened to adjust the adjustment bolt 59.
Is rotated by an appropriate angle, the retainer 62 is advanced and retracted, and the initial position of the cam piston 57 can be adjusted.

Since the structure of the centrifugal mechanism 29 and the other components are substantially the same as those of the previous embodiment, the parts corresponding to those of the previous embodiment in FIG.
The same reference numerals are given and the description is omitted.

In the above embodiment, various design changes can be made without departing from the gist of the present invention. For example, in a high-speed engine, when the rotation speed of the centrifugal mechanism 29 is high and the centrifugal force of the centrifugal weight 32 is too high, the driving of the centrifugal mechanism 29 is controlled so that the rotation speed of the centrifugal mechanism 29 is suppressed lower than that of the clutch mechanism 9. A system can also be constructed.
Further, an electric motor may be used instead of the engine E as the prime mover.

[0049]

As described above, according to the first aspect of the present invention, a clutch mechanism having a driving friction element connected to an input member and a driven friction element connected to an output member, and an increase in the rotational speed of the input member And a centrifugal mechanism including a centrifugal mechanism for increasing the clutch engagement force by pressing the driving friction element and the driven friction element against each other in accordance with the driving mechanism. With this configuration, it is possible to provide the clutch mechanism and the centrifugal mechanism with rotation speeds adapted to their respective functions, thereby increasing the degree of freedom in designing the clutch mechanism and the centrifugal mechanism.

According to the second feature of the present invention, since the speed ratio between the input member and the centrifugal mechanism is set to be higher than the speed ratio between the input member and the driving friction element, the rotational speed of the clutch mechanism is relatively low. It is possible to reduce the torque shock at the time of gear shifting due to the inertial rotation of the driven friction element system, and to provide a relatively high rotation speed to the centrifugal mechanism to reduce its size. Can be given.

According to a third feature of the present invention, a drive friction element decelerated from a drive shaft of a prime mover as an input member is rotatably provided on a main shaft of a transmission as an output member, and a driven friction element is connected to the drive shaft. Since the main shaft is provided with a centrifugal mechanism driven at the same speed from the drive shaft,
By keeping the number of revolutions of the clutch mechanism lower than that of the prime mover,
The torque shock at the time of gear shifting caused by the inertial rotation of the driven friction element system can be reliably mitigated, and the centrifugal mechanism is given the same number of revolutions as the prime mover to reduce its size. Thrust can be given.

Further, according to a fourth aspect of the present invention,
A clutch outer rotatably supported on the main shaft and driven from the drive shaft via a reduction gear train, a plurality of driving friction elements slidably spline-fitted to the inner periphery of the clutch outer; A clutch mechanism is constituted by a plurality of driven friction elements alternately arranged adjacent to the driving friction element and slidably spline-fitted to the outer periphery of a clutch inner connected to the main shaft, and rotatably supported on the main shaft. A cam plate driven from the drive shaft via the same speed gear train, a thrust plate disposed close to and separable from the cam plate, and a thrust plate interposed between the cam plate and the thrust plate. The centrifugal mechanism is made up of a centrifugal weight that gives thrust to the thrust plate by moving outward in the radial direction with an increase in centrifugal force, and thrust transmitting means that transmits the thrust generated by the thrust plate to the clutch mechanism as clutch engagement force. Since form was, regardless of the rotational speed difference between the clutch mechanism and the centrifugal mechanism can be provided appropriately to the clutch mechanism centrifugal thrust of centrifugal weights as a clutch engagement force.

According to a fifth aspect of the present invention, a clutch mechanism having a driving friction element connected to an input member and a driven friction element connected to an output member; In a centrifugal clutch including a centrifugal mechanism that presses the friction element and the driven friction element together to increase the clutch engagement force, the clutch mechanism and the centrifugal mechanism are connected to each other so as to be relatively rotatable. Thus, the number of rotations adapted to each function can be given without difficulty, and the degree of freedom in designing the clutch mechanism and the centrifugal mechanism can be increased.

Further, according to the sixth aspect of the present invention, the clutch mechanism and the centrifugal mechanism are arranged coaxially adjacent to each other, so that the centrifugal clutch including the clutch mechanism and the centrifugal mechanism can be made compact.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional plan view of a main part of a power unit for a motorcycle including a centrifugal clutch according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of the centrifugal clutch unit of FIG.

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a longitudinal sectional plan view of a main part of a power unit for a motorcycle having a centrifugal clutch according to a second embodiment of the present invention.

FIG. 5 is an enlarged view of the centrifugal clutch unit of FIG.

[Description of Signs] E ··· Prime mover (engine) T ··· Transmission 2 ··· Input member (drive shaft, crankshaft) 3 ··· Main shaft as output shaft 9 ··· Clutch mechanism 10 Clutch outer 11 Clutch inner 12 Drive friction element (drive friction plate) 13 Driven friction element (driven friction plate) 18 Reduction gear train 29 Centrifugal Mechanism 30: Same-speed gear train 31: Cam plate 32: Centrifugal weight 33: Thrust plate 38: Thrust transmission means

Claims (6)

[Claims] A clutch mechanism (9) including a driving friction element (12) connected to an input member (2) and a driven friction element (13) connected to an output member (3), and rotation of the input member (2). The number of the driving friction elements (1
2) and a centrifugal mechanism (29) for increasing the clutch engagement force by pressing the driven friction element (13) against each other, wherein the input friction member (2) drives the driving friction element (12) and the centrifugal mechanism (29). 29) The centrifugal clutch, wherein each of the clutches is driven with a different speed ratio. 2. The speed ratio between the input member (2) and the centrifugal mechanism (29) is set larger than the speed ratio between the input member (2) and the driving friction element (12). A centrifugal clutch, characterized in that: 3. The driving friction element (3), which is driven at a reduced speed from a drive shaft (2) of a prime mover (E) as an input member, to a main shaft (3) of a transmission (T) as an output member. A centrifugal mechanism (29) which is rotatably provided, connects the driven friction element (13), and is driven by the main shaft (3) at the same speed as the drive shaft (2).
A centrifugal clutch, characterized by having a clutch. 4. The clutch outer (10) according to claim 3, wherein the clutch outer (10) is rotatably supported on the main shaft (3) and is driven from the drive shaft (2) via a reduction gear train (18). And this clutch outer (10)
A plurality of driving friction elements (12) slidably fitted to the inner periphery of the driving friction element (12), and a clutch inner (11) arranged alternately adjacent to the driving friction elements (12) and connected to the main shaft (3). A clutch mechanism (9) is constituted by a plurality of driven friction elements (13) slidably fitted on the outer periphery of 11), and is rotatably supported by the main shaft (3) and the drive shaft (2). A cam plate (31) driven from the same through a gear train (30), a thrust plate (33) arranged close to and away from the cam plate (31), and these cam plates (31)
And a centrifugal weight (32) interposed between the thrust plate (33) and moving radially outward with an increase in centrifugal force to apply a thrust to the thrust plate (33), and a thrust plate (33) A centrifugal clutch comprising a centrifugal mechanism (29) and a thrust transmitting means (38) for transmitting a thrust to a clutch mechanism (9) as a clutch engaging force. 5. A clutch mechanism (9) including a driving friction element (12) connected to the input member (2) and a driven friction element (13) connected to the output member (3), and rotation of the input member (2). The number of the driving friction elements (1
2) and a centrifugal mechanism (29) for increasing the clutch engagement force by pressing the driven friction element (13) against each other, wherein the clutch mechanism (9) and the centrifugal mechanism (29) rotate relative to each other. A centrifugal clutch that is connected as possible. 6. The centrifugal clutch according to claim 5, wherein the clutch mechanism (9) and the centrifugal mechanism (29) are arranged coaxially adjacent to each other.