JPH0765628B2 - Friction clutch - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a multi-disc friction clutch provided in a power transmission device of a motorcycle or the like.

[Technical background of the invention and its problems]

This type of multi-plate friction clutch includes a cylindrical clutch housing driven by a crankshaft, a clutch inner connected to a driven shaft, a plurality of clutch plates and clutch discs respectively engaged with the clutch inner, and a pressing body for pressing a clutch spring with a clutch spring. The power from the engine is transmitted to the rear wheels via the transmission. However, if an excessive reverse load (back load) acts on the driven shaft due to sudden engine braking, for example, Excessive force acts on the vehicle body supporting the device and the rear wheels, resulting in a significant decrease in durability.

[Object of the Invention]

The present invention has been made in consideration of such circumstances, and absorbs an excessive reverse load from the driven shaft when a reverse load from the driven shaft acts between the clutch inner and the driven shaft. ,
An object of the present invention is to provide a friction clutch that is prevented from being transmitted to the drive side.

[Outline of Invention]

In order to achieve the above-mentioned object, a friction clutch according to the present invention includes a clutch housing driven by a drive source, a clutch inner rotatably provided on a driven shaft, and a plurality of clutches respectively engaged with these. A friction clutch including a plate and a clutch disc, and a pressing body that receives the elastic force of a clutch spring to press the clutch plate and the clutch disc so as to frictionally engage each other. A slider that is slidable is provided on the slider, and the clutch spring is mounted between the slider and the pressing body. On the other hand, a slider spring is provided on the opposite side of the clutch spring with the slider interposed therebetween. In addition to repulsing the spring and the opposite direction,
The spring constant of the slider spring is set to be larger than that of the clutch spring, and a slider cam provided on the slider and an inner cam provided on the clutch inner are engaged with each other, and when a reverse load is applied from the driven shaft, the slider is It is characterized in that the cam shapes of the slider cam and the inner cam are set so as to slide on the slider spring side.

Example of Invention

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 shows an engine for a motorcycle, in which power from an engine that is a drive source is transmitted to a crankshaft 1, and the transmitted power is a counter which is a driven shaft from a drive gear 2 provided on the crankshaft 1. It is transmitted to the driven gear 4 rotatably mounted on the shaft 3. The power transmitted to the driven gear 4 is transmitted to the counter shaft 3 via the friction clutch device 5, and subsequently to the drive shaft 7, the sprocket 8, and the transmission shaft 6 via the transmission 6.
It is transmitted to the chain 9 and drives a rear wheel (not shown).

The friction clutch device 5 is configured as shown in FIG. 1, and has a cylindrical clutch housing 11 mounted on the driven gear 4 via a damper 10. The clutch housing 11 is formed with a plurality of grooves 11a on its cylindrical surface.
A protrusion on the outer peripheral portion of the clutch plate 12 is engaged with 1a. The clutch plate 12 is attached to the clutch housing 11 so as to rotate integrally and slidably in the axial direction.

Further, a clutch inner 13 rotatably supported on the counter shaft 3 is arranged in the inner peripheral portion of the clutch housing 11, and a groove is formed in the outer peripheral portion of the clutch inner 13.
13a is formed. The clutch disc 14 is placed in this groove 13a.
The projections on the inner peripheral portion of are engaged. While the clutch discs 14 are axially stacked alternately with the clutch plates 12,
The clutch disc 14 is attached to the clutch inner 13 so as to be rotatable and slidable in the axial direction.

Further, the side surface of the clutch plate 12 receives the elastic force of the disc spring-shaped clutch spring 15 and
A pressing body 16 is provided which presses 12 and the clutch disk 14 and frictionally engages both members 12, 14 with each other.

On the other hand, the push piece 17 is inserted in the shaft hole of the counter shaft 3.
Is slidably mounted, and the push piece 17 slides inward in the axial direction by the rotation of the clutch release 18. When the push piece 17 slides inward in the axial direction, the pressing body 16 is pressed inward against the elastic force of the clutch spring 15, and the frictional engagement between the clutch plate 12 and the clutch disc 14 is cut off.

Therefore, the rotation of the crankshaft 1 is caused by the drive gear 2
And transmitted to the clutch housing 11 via the driven gear 4, but the clutch plate 12 and the clutch disc 14
The clutch shaft 13 is not transmitted to the clutch inner 13 and therefore the counter shaft 3 does not rotate. The rotation of the clutch release 18 can be arbitrarily performed by a manual operation of an occupant of the motorcycle.

The counter shaft 3 is provided with a spline 19,
A slider 20 is fitted in the spline 19 so as to be slidable in the axial direction and integrally rotated. A convex slider cam 21 is integrally formed on a side portion of the slider 20, and the slider cam 21 is engaged with a concave inner cam 22 integrally provided on the clutch inner 13.

Further, the slider 20 is integrally formed with a flange-shaped spring stopper 23.
The clutch spring 15 is elastically mounted between the pressing body 16 and the pressing body 16, and a slider spring 24 is provided on the opposite side of the clutch spring 15 with the spring stopper 23 interposed therebetween.

The slider spring 24 is a combination of two disc springs. The slider spring 24 and the clutch spring 15
Are repulsing in opposite directions. This allows the slider
20 is pressed toward the clutch inner 13 side together with the clutch spring 15 and is biased by a spring in a direction to deepen the engagement between the slider cam 21 and the inner cam 22.

Since the spring constant of the slider spring 24 is set larger than that of the clutch spring 15,
When the pressing body 16 is pressed inward by the operation of the push piece 17 and the clutch release 18, the clutch spring 15 is compressed but the slider spring 24 is not compressed.

The shapes of the slider cam 21 and the inner cam 22 are set so as to separate the slider 20 from the clutch inner 13 and slide toward the slider spring 24 side when a counter load is applied to the counter shaft 3 as described later. (See Figures 2 and 3).

Next, the clutch action of the friction clutch thus configured will be described.

In a normal traveling state in which power is transmitted from the engine of the motorcycle to the rear wheels, the slider cam 21 is spring-biased by the slider spring 24 and deeply engaged with the inner cam 22 as shown in FIGS. The power transmitted to the inner 13 is transmitted from the power transmission surface 22a of the inner cam 22 to the slider 20 via the power transmission surface 21a of the slider cam 21, and is transmitted from the slider 20 to the counter shaft 3. At this time, the clutch spring 15 presses the pressing body 16 with a predetermined elastic force, and provides a sufficient frictional force between the clutch plate 12 and the clutch disc 14 to transmit the driving force.

On the other hand, when power is transmitted from the rear wheels to the engine due to abrupt engine braking, the reverse load transmitted to the counter shaft 3 is transmitted to the slider 20, and the cam acting surface 21b of the slider cam 21 moves to the inner cam 22. Although transmitted to the cam acting surface 22b, since the cam acting surfaces 21b and 22b are formed obliquely to each other, the slider 20 is acted by this cam to cause the slider 20 to reverse load transmitting surface 21c of the slider cam 21 and the inner cam 2.
2 Relative rotation to the position where the reverse load transmission surface 22c abuts,
The slider 20 slides toward the slider spring 24 side.

While the slider spring 24 is compressed by the spring stopper 23 as the slider 20 slides, one end (inner circumference) of the clutch spring 15 locked by the spring stopper 23 moves inward and the clutch spring 15 extends. To be done.

Therefore, the elastic force that presses the pressing body 16 toward the clutch inner 13 side is weakened, the frictional force between the clutch plate 12 and the clutch disc 14 decreases, and the slip between the clutch plate 12 and the clutch disc 14 causes an excessive force. The reverse load is absorbed.

According to the friction clutch 5 configured as described above, the clutch plate 12 and the clutch disc 14 are in a normal traveling state.
The frictional force between the two has a sufficient frictional force to transmit the driving force, and the slider 20 can move in the axial direction by the cam action of the inner cam 21 and the slider cam 22 when a reverse load due to a sudden engine brake acts. To reduce the elastic force of the clutch spring 15 and the clutch plate 12 and the clutch disc.
The frictional force between 14 can be reduced and an excessive reverse load can be absorbed, preventing an excessive force from acting on the engine, the transmission and the vehicle body that supports the rear wheels, and improving reliability and durability. Can be improved.

Moreover, the clutch spring 15 and the slider spring 24
Are provided so as to repel each other in opposite directions with the slider 20 interposed therebetween, the movement of the slider 20 when a reverse load is applied from the driven shaft 3 side is accurately controlled, and the clutch is quickly and smoothly operated. It can be slipped to absorb reverse loads. Therefore, proper engine braking is applied, smooth deceleration is possible, and a good driving feeling is obtained.

Furthermore, since the elastic force of the clutch spring 15 is not weakened except when a reverse load is applied from the driven shaft 3 side, the vehicle can be started without increasing the contact area of the clutch plate 12 and the clutch disc 14. Sufficient clutch capacity can be obtained immediately after upshifting, and good acceleration response can be obtained, which can also contribute to downsizing of the engine.

Further, since the slider cam 21 and the inner cam 22 are deeply engaged with each other when a positive load is applied from the drive shaft 1 side, there is no fear of strength related to power transmission, and therefore, the slider 20 and the clutch inner 13 are not in contact with each other. The width can be made thin, and by doing so, the overall width of the friction clutch 5 can be narrowed to further contribute to downsizing of the engine.

In the friction clutch 5, since the clutch spring 15 and the slider spring 24 are orthodox disc springs, it is difficult for the spring constant to change due to aging, and the performance of the initial clutch can be maintained for a long time.
Since the ratio of the spring constants of the clutch spring 15 and the slider spring 24 can be freely combined,
Optimal clutch performance (reverse load absorption performance) can be provided according to the type of engine, gear ratio, vehicle type, and the like.

〔The invention's effect〕

With the friction clutch according to the present invention having the above-described configuration, an excessive reverse load is effectively absorbed, and the durability and reliability of the vehicle body that supports the engine, the transmission, and the rear wheels are improved. , The appropriate engine plate is added to enable smooth deceleration, sufficient clutch capacity is obtained without increasing the size of the friction clutch, providing good acceleration response, and it is also great for compacting the engine. You can contribute.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a friction clutch according to the present invention, FIGS. 2 and 3 are views for explaining the clutch action of the friction clutch, and FIG. 4 is a plan view of an engine of a motorcycle. is there. 3 ... Counter shaft as driven shaft, 11 ... Clutch housing, 12 ... Clutch plate, 13 ... Clutch inner, 14 ... Clutch disc, 15 ... Clutch spring,
16 ... Pressing body, 20 ... Slider, 21 ... Slider cam, 22 ... Inner cam, 24 ... Slider spring.

Claims (1)

[Claims] 1. A clutch housing driven by a drive source, a clutch inner rotatably provided on a driven shaft, a plurality of clutch plates and clutch discs respectively engaged with the clutch inner, and an elastic force of a clutch spring. In a friction clutch including a pressing body that receives the clutch plate and the clutch disc to frictionally engage each other, a slider that is rotatable and integrally slidable in the axial direction is provided on the driven shaft. While the clutch spring is elastically mounted between the pressing body and the slider, the slider spring is provided on the opposite side of the clutch spring with the slider interposed therebetween, and the slider spring and the clutch spring are repulsed in opposite directions.
The spring constant of the slider spring is set to be larger than that of the clutch spring, and a slider cam provided on the slider and an inner cam provided on the clutch inner are engaged with each other, and when a reverse load is applied from the driven shaft, the slider is A friction clutch, wherein the cam shapes of the slider cam and the inner cam are set so as to slide on the slider spring side.