JPH03189284A - Rear wheel suspension device for motorcycle - Google Patents

Abstract

PURPOSE:To easily protect a fluctuating angle detecting part from jumping stones, mud, and the like, by providing the fluctuating angle detecting part on the upper end part side of a damper supporting fluctuatable rear arms rotatably supporting a rear wheel on their rear ends. CONSTITUTION:A pair of right and left rear arms 11 are pivotally supported with a seat pillar 2, and a damper 13 provided with a variable damping force generating device (not shown in the figure) is provided between the cross member reinforcing the front end parts of the rear arms 11 and a seat rail 3. In the variable damping force generating device, the opening degree of a restrictor to adjust restriction of an orifice is adjusted corresponding to the fluctuating angle of the rear arms 11, and the fluctuating angle is detected with a fluctuating angle detecting part S. In this case, the fluctuating angle detecting part S arranged on the upper end part side of the damper 13 is constituted out of a follower 18 provided on the extreme end of a rod 17 penetrating to the upper end side through the center of a piston rod 16 connected with the restrictor and a cam 19 fixed on the seat rail side.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a rear wheel suspension for a motorcycle in which a rear arm is supported by a shock absorber equipped with a variable damping force generator that changes damping force according to the swing angle of the rear arm. Regarding equipment.

[Prior art]

A rear wheel suspension system for a motorcycle is configured so that the rear arm is suspended from the vehicle body frame using a shock absorber.
Some vehicles have only one shock absorber, and this one shock absorber supports a pair of left and right rear arms at an intermediate portion in the vehicle width direction. Additionally, some vehicles are equipped with a variable damping force generator that can change the damping force of the shock absorber in accordance with the swing angle of the rear arm.

By the way, in the conventional rear wheel suspension system of a motorcycle, the swing angle detection section of the variable damping force generating device is provided at the lower end of the shock absorber, and the lower end is connected to the upper edge of the rear arm. I was doing it. However, with this type of connection structure, in motorcycles such as motocrossers that run on unpaved roads, the rocking angle detection part may become dirty or damaged due to flying stones or mud hitting the connection part of the shock absorber. Sometimes,
This sometimes made it impossible to make variable adjustments to the damping force.

[Problem to be solved by the invention]

An object of the present invention is to provide a motorcycle equipped with a variable damping force generator in a rear wheel suspension shock absorber, in which variable adjustment of the damping force becomes impossible due to staining or damage to the swing angle detection section of the rear arm, as in the past. An object of the present invention is to provide a rear wheel suspension system that prevents this from occurring.

Means for Solving Problem C] The present invention achieves the above object by providing the shock absorber with a variable damping force generator that changes the damping force according to the swing angle detected by the swing angle detection section of the rear arm. In a motorcycle in which a lower end portion of a shock absorber is connected to an intermediate portion in the vehicle width direction of a pair of left and right rear arms, and an upper end portion thereof is connected to a vehicle body frame, the swing angle detection portion is provided on the upper end side of the shock absorber. It is characterized by this.

By providing the t8 swing angle detecting section on the upper end side of the buffer, the swing angle detecting section can be protected from flying stones and mud.

〔Example〕

The embodiments shown in the figures will be explained below.

In FIG. 1, 1 is a main frame, 2 is a seat pillar, and 3 is a seat rail, which constitute a vehicle body frame. Also, 4 is the engine, 5 is the seat, 6 is the front wheel, 7
is the rear wheel.

A carburetor 8 is attached to the intake side of the engine 4, and an air cleaner 9 is further connected to the carburetor 8.

``10 is the exhaust pipe.

A pair of left and right rear arms 11.11 are pivotally supported by the seat pillar 2, and support the rear wheel 7 at their rear ends. The rear arms 11, 11 are suspended by one shock absorber 13 placed in the middle in the vehicle width direction, and the lower end of the shock absorber 13 is connected to the center of the rear arm 11.11 in the vehicle width direction, and the upper end is connected to the center of the rear arm 11.11 in the vehicle width direction. It is connected to the seat rail 3.

The shock absorber 13 has a known structure and is composed of a cylinder 14 into which hydraulic oil and a piston are inserted, and a spring 15. However, in the shock absorber of this embodiment, the upper and lower mounting directions are opposite to the conventional general mounting direction, and the cylinder 14 is on the rear arm 11 side.

Further, the shock absorber 13 is equipped with a variable damping force generating device (not shown) having a known configuration. The variable damping force generator is configured such that an orifice passes through the piston in the axial direction, and the throttle of the orifice is adjusted in accordance with the swing angle of the rear arm 11 via a throttle valve.

The swing angle detection section S of the rear arm 11 is provided with a rod 17 to which the throttle valve is connected so as to pass through the center of the piston rod 16 toward the upper end, as shown in FIG. 2, and provided at the tip of the rod 17. The follower 18 is configured to come into contact with a cam 19 fixed to the seat rail 3 side. When the rear arm 11 swings, the follower 18 moves along the surface of the cam 19 in accordance with the swing angle, so that the rod 17 moves in the axial direction to adjust the throttle valve.

In the embodiment shown in Fig. 1.2, the cylinder 14 of the shock absorber 13 is installed upside down compared to the conventional mounting direction.
The so-called unsprung load can be increased, making it easier to maneuver. However, the shock absorber according to the present invention may be mounted in the same manner as the conventional one as shown in FIG. Also in the case of the embodiment shown in FIG. 3, the cam 1
The swing angle detection unit S between 9 and the follower 18 must have a buffer δ13.
It must be provided on the upper end side A of the

Also, when the shock absorber 13 is installed in either the direction shown in FIG. 1.2 or FIG. 3, the cam 19 of the swing angle detection section
is fixed to the vehicle frame. Preferably, the fourth and fifth
As shown in the figure, it is preferable to attach it to the seat rail 3. In the example shown in FIGS. 4 and 5, a pair of brackets 12.12 are welded to the pair of left and right seat rails 3, 3, and a cam 19 is inserted between these brackets 12.12, and is removably fixed with bolts 20. It is now possible to do so. By making the cam 19 detachable in this manner, it becomes easy to replace the cam 19, and it becomes possible to change the damping force in various ways.

By providing the swing angle detection section S at the upper end of the shock absorber 13 as described above, the swing angle detection section S can be protected from flying stones and mud by 4 degrees. In particular, the upper end of the shock absorber is not only placed at a high position, but also an air cleaner.

Since it is also protected by a frame, a side cover (not shown), etc., reliable protection can be achieved.

C Effects of the Invention As described above, the present invention provides a motorcycle in which a shock absorber for rear wheel suspension is equipped with a variable damping force generation device, in which a swing angle detection section is provided on the upper end side of the shock absorber. , the swing angle detection section can be protected from flying stones and mud, and there is no possibility that variable adjustment of the damping force becomes impossible due to dirt or damage, unlike in the past.

[Brief explanation of drawings]

FIG. 1 is a side view of a motorcycle equipped with a rear wheel suspension system according to the present invention, FIG. 2 is a side view of main parts showing details of the shock absorber portion of the motorcycle, and FIG. 3 is a main part according to another embodiment. FIG. 4 is a side view showing an example of a structure in which the cam of the swing angle detecting section is mounted, and FIG. 5 is a view taken along arrow V-■ in FIG. 4. l... Main frame, 2... Seat pillar, 3.
...Seat rail, 11...Rear arm, 13...
Buffer, 14... Cylinder, 16... Piston rod, 17... Lid, 18... Follower, 19...
・Cam, 20... Bolt, S... Swing angle detection section.

Claims (1)

[Claims] The shock absorber is provided with a variable damping force generator that changes the damping force in accordance with the swing angle detected by the swing angle detection section of the rear arm, and the lower end of the shock absorber is connected to the intermediate portion in the vehicle width direction of the pair of left and right rear arms. Further, a rear wheel suspension device for a motorcycle, wherein the upper end of the motorcycle is connected to a body frame, wherein the rocking angle detection section is provided on the upper end side of the shock absorber.