JPS5933770B2 - friction plate clutch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a driven member having a clutch housing driven by engine torque and a friction plate coupled to an input shaft of a transmission and frictionally engaged with a friction plate provided on the clutch housing. The present invention relates to an improvement in a friction plate clutch comprising a pressure plate which is movably provided in the clutch housing in the axial direction and presses the friction plate, and a spring which applies a pressing force to the pressure plate.

Conventionally, in this type of friction plate clutch, in order to transmit a large engine torque to a driven member, a spring with a large biasing force is used to increase the pressing force on the pressure plate, and the frictional engagement force between the friction plates is increased. needs to be made larger.

For this reason, the operating load of the clutch lever that releases the pressing force of the pressure plate inevitably increases, and its operability deteriorates. This tendency was particularly strong in motorcycles equipped with high-output engines. The present invention has been made in view of the above-mentioned drawbacks, and its main purpose is to provide a friction plate clutch of this type in which the frictional engagement force between the two friction plates increases in response to an increase in engine torque. The object of the present invention is to ensure that the clutch lever is transmitted to the driven member, and to reduce the operating load of the clutch lever, thereby improving its operability. Hereinafter, one embodiment of the present invention will be described based on the drawings. 1st
The figure shows a schematic diagram of a friction plate clutch 1 of the present invention incorporated into a power transmission mechanism of a motorcycle.
The rotation is transmitted to the input shaft 10 of the transmission via the chain 3. This friction plate clutch 1 has a second
As shown in the figure, a clutch housing 20 is provided on an input shaft 10 of a transmission which is rotatably supported by a crankcase via a bearing and whose movement in the axial direction is restricted, and a clutch housing 20 is spline-coupled to the input shaft 10. The clutch boss 30 is fixed to the clutch boss 30, and the pressure plate 40 is provided inside the clutch housing 20 on the input shaft 10 so as to be movable in the axial direction. The clutch housing 20 is driven by engine torque, and has a large number of slits 21 on its outer circumferential wall that communicate with its opening side edge, and the clutch boss 30 has a large number of grooves on its outer circumferential wall that communicate with both ends thereof. 31 and a large number of clutch plates 2
2 and a large number of friction plates 32 form the slit 21
The studs are alternately arranged between the clutch housing 20 and the clutch boss 30 along the groove 31. The movement of the clutch plate 22 and the friction plate 32 in the axial direction (rightward in the figure) is restricted by a circlip 33 attached to the outer peripheral edge of the clutch housing 20. The pressure plate 4.0 is urged toward the clutch boss 30 by a spring 24 whose one end is locked to an annular spring receiver 23 supported within the clutch housing 20, and this urging force causes the clutch plate 22 and the friction plate 32 with the circlip 3.
3 and press. Therefore, these plates 22 and 32 are in frictional engagement with each other, and the engine torque is transmitted from the clutch housing 20 to the clutch boss 30 via these plates 22 and 32 to the input shaft 10 of the transmission.
transmitted to. Note that the reference numeral 11 indicates a pushbutton fitted into the input shaft 10, which pushes the pressure plate 40 to the left in the figure via the bushing par 12 in conjunction with the operation of a clutch lever (not shown). The frictional engagement between 22 and friction plate 32 is released. Therefore, the casing 50 and the sleeve 6 are disposed on the shaft support 25 of the clutch housing 20.
0 is assembled.

The casing 50 is fitted onto the shaft support 25 so as to be relatively rotatable and is restricted from moving in the axial direction, and a sprocket 70 for transmitting the drive of the crankshaft 2 is fixed to the outer periphery of the casing 50. Further, a pin 52 that projects outward is implanted in the fitting portion 51 of the casing 50. As shown in FIGS. 2 to 4, the sleeve 60 has an annular flange 61 at one end and three projecting pieces 62 at the other end. As clearly shown in , an arcuate cam hole 63 into which the pin 52 implanted in the casing 50 is inserted is bored. Note that the shape of the cam hole 63 is appropriately determined depending on the relationship between engine torque and inertia torque, which will be described later. The sleeve 60 is assembled onto the fitting portion 51 of the casing 50 so as to be rotatable relative thereto and movable in the axial direction, and the engagement force against the cam surface of the pin 52 fitted into the arcuate cam hole 63 is Its axial movement is restricted by. In addition, the sleeve 60 is biased toward its retracted position by locking the other end of a resilient member 80, which is made up of three disc springs with one end locked to the casing 50, to the flange portion 61 of the sleeve 60. The three protruding pieces 62 of the sleeve 60 are brought into contact with the spring receiver 23 through the three insertion holes 26 provided in the clutch housing 20, and are engaged with the spring 24 via the spring receiver 23. . In addition, the protruding piece 62
is formed to be movable in the axial direction of the input shaft 10 within the insertion hole 26, but not movable in the rotational direction thereof. For this reason,
The sleeve 60 integrally drives the clutch housing 20 by engaging the protruding piece 62 in the insertion hole 26, and in its retracted position (shown in the second figure), the length of the spring 24 is at its maximum extension. Spring receiver 23
Press. Next, the operation of the friction plate clutch 1 configured as described above will be explained. In this friction plate clutch 1, engine torque is transmitted to the casing 50 by the chain 3 wound around the sprocket 70, and further to the casing 50. It is transmitted to the clutch housing 20 via the implanted pin 52 and sleeve 60, and drives the clutch housing 20 to rotate.

Further, the pressure plate 40 presses the clutch plate 22 and the friction plate 32 by the urging force of the spring 24, and both plates 22, 3
2 are frictionally engaged, the clutch housing 20
The rotational driving force is transmitted to the clutch boss 30 via these plates 22, 32, and rotationally drives the input shaft 10, which is integrated with the clutch boss 30. In this friction plate clutch 1, when the engine is stopped, that is, when the engine torque is zero, the sleeve 60 is in its retracted position due to the urging force of the elastic member 80 and the spring 24, and is inserted into the casing 50. As shown in FIG. 4a, the provided pin 52 is positioned so as to engage with the rightmost cam surface of the arc-shaped cam hole 63 (neutral position). 50 and the pin 52 installed therein, and the engine torque gradually increases, the pin 52 gradually moves, for example, upward in the figure along the cam surface of the cam hole 63, and reaches the position shown by the imaginary line. .

During this time, the sleeve 60 moves to the right in the figure due to the engagement force of the pin 52 with the cam surface against the urging force of the resilient member 80 and the spring 24, and pushes the spring receiver 23! The pressing force of pressure plate 40 against clutch plate 22 and friction plate 32 is increased. On the other hand, when the engine torque is reduced and the inertia torque of the vehicle becomes large (during engine braking), the sleeve 60 moves upward in the figure. In other words, pin 5
2 instantaneously moves downward in the figure through the neutral position along the cam surface, and gradually returns to the neutral position as the inertial torque decreases. Therefore, in this friction plate clutch 1, when the engine torque is small, such as when the engine is idling, the pin 52 is in a substantially neutral position, so that the biasing force of the spring 24 against the pressure plate 40 is small. , the clutch lever can be operated easily before changing the transmission (the operating load on the clutch lever is small).

Furthermore, when the accelerator is released to change the transmission while the vehicle is running, the pin 52 instantly moves downward through the neutral position, so if the clutch lever is operated at the same time as the accelerator is released, the clutch You can easily operate the lever. Furthermore, when the engine torque is increased to run the vehicle at high speed, pin 5
2 is in the upper position shown by the imaginary line in FIG. Both plates 22 and 32 reliably transfer the engine torque to the input shaft 1 by a large frictional engagement force corresponding to the large engine torque.
0 to properly accelerate the vehicle.
FIG. 4b shows another embodiment of an arc-shaped cam hole.This cam hole 63 is formed in an arc shape only on one side with respect to the neutral position of the pin 52, and is formed only when the engine torque increases. The sleeve 60 is moved to the right in the figure to increase the frictional engagement force between the clutch plate 22 and the friction plate 32, and when the inertial torque of the vehicle is large, the sleeve 60 is moved to the left in the figure to reach its retreated position,
The operating load on the clutch lever is always reduced when the accelerator is released.

It should be noted that the above description is based on one embodiment of the present invention, and the present invention is not limited to this, and can be implemented with appropriate modifications within the scope of the gist of the present invention. be.

In summary, the present invention provides a friction plate clutch including: a rotating body that is relatively rotatably assembled to a clutch housing and driven by engine torque; a sleeve having an arcuate cam hole into which a pin provided on the rotating body is fitted, and one end of which engages via a spring receiver with a spring that applies a pressing force to the pressure plate through a part of the clutch housing; The structure is characterized in that the sleeve increases the pressing force of the spring by the engagement force of the pin with the cam surface of the cam hole in response to the engine torque applied to the sleeve.
This makes it possible to increase the frictional engagement force between the friction plates in response to an increase in engine torque, thereby reliably transmitting the engine torque to the driven member, and to reduce the operating load when operating the clutch lever. It is possible to improve its operability.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a power transmission mechanism of a motorcycle incorporating a friction plate clutch according to the present invention, FIG. 2 is a longitudinal side view showing an embodiment of the friction plate clutch according to the present invention, and FIG. is a vertical sectional front view taken along the line ■-■ in Fig. 2, Fig. 4a is a schematic plan view showing the relationship between the pin and the cam hole, and Fig. 4b is a schematic plan view showing another embodiment of the cam hole. be. Explanation of symbols, 1...Friction plate clutch, 2...
...Crankshaft, 3...Chain, 1
0...Transmission input shaft, 20...Clutch housing, 22...Clutch plate,
23... Spring holder, 24... Spring, 30... Clutch boss, 32...
...Friction plate, 40...Pressure plate, 50...Casing, 52...
...Pin, 60...Sleeve, 63,63!
......Circular cam hole, 80...Elastic repellent member.

Claims (1)

[Claims] 1. A clutch housing driven by engine torque; a driven member having a friction plate coupled to an input shaft of a transmission and frictionally engaged with a friction plate provided on the clutch housing; In a friction plate clutch comprising a movably provided pressure plate that presses the friction plate and a spring that applies a pressing force to the pressure plate, the friction plate clutch is assembled to the clutch housing so as to be relatively rotatable and is rotated by engine torque. It has a rotating body to be driven, and is assembled to the rotating body so as to be relatively rotatable, and has an arc-shaped cam hole in its peripheral wall into which a pin provided on the rotating body is fitted, and one end of the circular cam hole is inserted through a part of the clutch housing. A sleeve is provided that engages with the spring via a suitable spring receiver, and the sleeve is pressed against the spring by the engagement force of the regular pin against the cam surface of the cam hole in response to the engine torque applied to the rotating body. A friction plate clutch characterized by increasing pressure.