JPS61274158A - Power transmission mechanism for motor-cycle - Google Patents

Abstract

PURPOSE:To achieve the high reduction rate by the compact constitution and to prevent noise and vibration by constituting a reduction apparatus from a planetary frictional roller type reduction gear mechanism and installing, in series and in multistages, the planetary frictional roller type reduction mechanisms. CONSTITUTION:A reduction apparatus 4 is constituted of the series connection of a planetary frictional roller type reduction gear mechanism constituted of a sun roller 15 fixed onto a rotary shaft 13, a plurality of planetary rollers 16 in frictional contact on the outer periphery of the sun roller 15, and an outer ring 17, and a planetary frictional roller type reduction gear mechanism constituted of a sum roller 20, a plurality of planetary rollers 21, and the outer ring 17 Therefore, the reduction in high reduction rate is permitted with the compact constitution, and since the power can be transmitted through the friction due to the frictional roller, the generation of noise and vibration due to the meshing of gears can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a power transmission mechanism for a motorcycle.

[Prior art]

2. Description of the Related Art As a power transmission mechanism for a motorcycle that transmits engine power to drive wheels, there is one that is equipped with a gear reduction device and an automatic transmission with a V-belt or the like wrapped around it. Generally, if the above-mentioned winding is a power transmission system without a type automatic transmission, the total reduction ratio may be about 3 to 6:1, but the winding can be done with a type automatic transmission. Therefore, a high reduction ratio of about 9 to 15:1 is required.

For this reason, in conventional motorcycles that are equipped with a wrap-type automatic transmission in the power transmission system, the gear reduction gear inevitably becomes larger, which increases the size of the vehicle and increases the time when the gears mesh. There was a problem in that it increased noise and vibration such as the rattling sound of the teeth.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a power transmission mechanism for a motorcycle that has a compact configuration, yet can obtain a high reduction ratio, and can reduce noise and vibration.

[Structure of the invention]

To achieve the above object, the present invention provides a motorcycle in which engine power is transmitted to drive wheels via a winding type automatic transmission and a speed reduction device, in which the speed reduction device is connected to a planetary friction roller type speed reduction mechanism. The present invention is characterized in that this planetary friction roller type deceleration mechanism is provided in multiple stages in series.

〔Example〕

Hereinafter, the present invention will be explained with reference to embodiments shown in the drawings.

In the figure, 1 is an engine, 2 is a V-belt type automatic transmission, 3 is a centrifugal clutch, 4 is a reduction gear, and 5 is a rear wheel that serves as a driving wheel.

The engine 1 includes a cylinder 6 and a piston 7, and the reciprocating motion of the piston 7 rotates a crankshaft 8. The V-belt automatic transmission 2 is
A pair of split pulleys 9f and 9m provided on the crankshaft 8 side,
A pair of split pulleys 10f are provided on the rotating shaft 12 on the rear wheel 5 side.

10 m long, and a V-belt 11 wound between them. One of the split pulleys 9m provided on the crankshaft 8 side is operated as the rotational speed of the crankshaft 8 increases (as
It slides toward the other split pulley 9f, and the diameter of the V-belt 11 is increased. On the other hand, due to the change in diameter of this winding, one of the split pulleys 10m provided on the rotating shaft 12 side slides in the direction away from the split pulley 1Of, and the V-belt 11
Decrease the diameter of the winding. Therefore, the rotational speed transmitted from the crankshaft 8 to the rotating shaft 12 is automatically changed.

The power thus transmitted to the rotating shaft 12 is transmitted to the inner rotating shaft 13 via the centrifugal clutch 3.

The speed reduction device 4 is configured to reduce the speed of the power transmitted to the rotating shaft 13 and transmit it to the axle 14 of the rear wheel 5, and includes a planetary friction roller type speed reduction mechanism, which will be described later, connected in two stages in series. It is made up of the following: This planetary friction roller type speed reduction mechanism does not have only two stages as in this embodiment, but may have three or more stages.

As shown in FIG. 2, the first stage planetary friction roller type speed reduction mechanism includes a sun roller 15 fixed to a rotating shaft 13, and a plurality of planetary rollers 16. -・-・-116 and these planetary rollers 16
, - . . . , an outer ring 17 that is in frictional contact with the outside of the ring 16.

This outer ring 17 is configured in common with the outer ring of the second stage planetary friction roller type speed reduction mechanism, and is fixed to the case 18 side.

As shown in FIG. 3, the second stage planetary friction roller type deceleration mechanism has a plurality of planetary rollers 21, -1, 21 in frictional contact with the outer periphery of the sun roller 20, The common outer ring 17 is brought into frictional contact with the outside thereof. The sun roller 20 is formed integrally with a carrier 19 that supports the first stage planetary roller 16, and the carrier 22 that supports the planetary roller 21 is formed integrally with the axle 14 of the rear wheel 5. There is. In addition, the second stage planetary roller 2
The number of the planetary rollers 1 is different from that of the first stage planetary rollers 16, and the number of the former planetary rollers 21 is larger than that of the latter planetary rollers 16.

The deceleration bag R4 is composed of a planetary friction roller type deceleration mechanism as described above, and is connected in multiple stages in series, so it can decelerate at a high reduction ratio despite having a compact configuration. Therefore, engine 1
By interposing the V-belt type automatic transmission 2 in the power transmission system between the rear wheels 5 and the rear wheels 5, the total reduction ratio can be increased to approximately 9 to 15
Even if it is necessary to achieve a high reduction ratio of 1, the device will not be unnecessarily enlarged unlike conventional gear reduction devices. Furthermore, since power is transmitted by friction rollers, noise and vibrations such as rattling noise are not generated, unlike conventional gear transmission.

〔Effect of the invention〕

As described above, the present invention provides a motorcycle in which engine power is transmitted to drive wheels via a winding type automatic transmission and a speed reduction device, in which the speed reduction device is constituted by a planetary friction roller type speed reduction mechanism. In addition, since this planetary friction roller type reduction mechanism is arranged in multiple stages in series, the windings that require a large total reduction ratio can be easily applied even when an automatic transmission is interposed in the power transmission system. , its high reduction ratio can be achieved with a compact configuration.

Furthermore, since the power is transmitted by friction using friction rollers, noise and vibrations that occur when gears mesh are not generated.

[Brief explanation of the drawing]

Fig. 1 is a developed sectional view showing a power transmission mechanism of a scooter according to an embodiment of the present invention, Fig. 2 is a view taken along the nn arrow in Fig. 1, and Fig. 3 is a view taken along the mm arrow in Fig. 1. It is. 1--Engine, 2--■ Belt type automatic transmission (winding type automatic transmission), 4--Reduction device, 5-
... Rear wheel (drive wheel), 13-rotating shaft, 14--axle, 15.20-sun roller, 16°2 knee planetary roller, 17-outer ring, 19.22--carrier.

Claims (1)

[Claims] In a motorcycle in which engine power is transmitted to drive wheels via a wrap-type automatic transmission and a speed reduction device, the speed reduction device is composed of a planetary friction roller type speed reduction mechanism, and the planetary friction roller type speed reduction mechanism A power transmission mechanism for a motorcycle, characterized by having mechanisms arranged in multiple stages in series.