JPH0541475B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a front wheel suspension system that cushions and supports the front wheel of a motorcycle, and in particular, the present invention relates to a front wheel suspension system that cushions and supports the front wheel of a motorcycle. The front wheel is supported by the front wheel, and the middle part is connected to a buffer spring.
This invention relates to a so-called leading link type or trailing link type shock absorber.

[Prior art]

Leading link type or trailing link type front wheel suspension systems for motorcycles are often used in small motorcycles because their unsprung weight is light and their structure is simple (for example,
Publication No. 11123, Publication No. 11123, Publication No. 4582, Publication No. 4582, Publication No. 4582, Publication No. 4582, Publication No. 4582
−14807, etc.).

However, due to the structure of a front wheel suspension system such as a leading link type, when the swinging arm supporting the front wheel swings, the rod connecting the swinging arm and the buffer spring also swings. It cannot be used as a guide tube for the piston rod, and the entire shock absorber including the spring and guide tube must be swung, making it difficult to simplify the structure.

[Summary of the invention]

The purpose of this invention is to solve the above-mentioned problems. A support arm is provided at the lower end of the main pipe of the front fork, and the other end of the swinging arm, which supports the front wheel at one end, is rotated by the support arm. A piston is freely supported and slidably provided in the main pipe, and a swinging arm is connected to the piston by a rod, and the piston is resiliently downwardly repelled by a spring. The rod is formed of an elastic body that allows the rod to tilt due to its elastic deformation, and the rod is slidably fitted into the lower end of the main pipe of the front fork, and this bush is held on the axis of the main pipe. The piston and the rod are swingably supported with respect to the main pipe by providing a spring, and the rod connecting portion of the swinging arm is positioned closer to the center of swing than the connecting portion of the front wheel. be.

〔Example〕

The present invention will be explained below with reference to illustrated embodiments. 1 is a front fork of a motorcycle, and a front wheel 3 is supported at the lower ends of left and right main pipes 2, 2.

That is, as shown in FIG.
A support arm 4 is provided on the rear side of the lower end of the main pipe 2, and the lower end of this support arm 4 has an axle 3 of the front wheel 3 at one end.
A swinging arm 5 supporting a is swingably connected by a pivot 6.

A piston 7 is slidably fitted inside the main pipe 2 and is urged downward by a spring 8. A piston rod 9 is connected to the piston 7. A bracket 9a is fixed to the lower end of the piston rod 9, and the bracket 9a is rotatably connected to the swing arm 5 via a pin 11. The piston 7 consists of two washers 7a and 7b provided at the upper end of the piston rod 9, and a rubber-like elastic ring 7c interposed between them. The upper end of the piston rod 9 is guided in the axial direction along the inner surface of the main pipe 2 by the elastic ring 7c, and is allowed to tilt due to its elastic deformation. A bush 12 is slidably fitted onto the piston rod 9, and is placed on the axis of the main pipe 2 by a spring 15.
That is, this bush 12 holds the piston rod 9 approximately on the axis of the main pipe 2 by the spring force of the spring 15, thereby improving the ease of assembly. Reference numeral 13 designates a support ring for the bush 12, which is supported by a circular clip 14 at the lower end of the main pipe 2, and is also supported by a spring 15.
The bush 12 is supported through. 16
1 is a rubber damper, 17 is a rubber boot for dustproofing and waterproofing, and 18 is a steering shaft for attaching the front fork 1 to a vehicle body frame (not shown).

According to this embodiment, when the vehicle is running, the front wheels 3
When the main pipe 2 moves up and down, the swinging arm 5 swings up and down accordingly. The upward movement of the swinging arm 5 is accompanied by the upward movement of the bracket 9a, piston rod 9 and piston 7, and the spring 8 is compressed. front wheel 3
When the action of pushing up stops, the elasticity of the spring 8 causes the swinging arm 5 to move downward through the reverse process. Thus, a damping effect on the front wheels 3 is achieved. Here, the vertical movement of the swinging arm 5 causes the piston rod 9 and the piston 7 to swing back and forth, but the piston 7 is guided by the elastic ring 7c and accurately moves inside the main pipe 2 along its axis. Move to. Also,
The elastic ring 7c compresses and expands at the front and back to absorb the vibration, and no gap is created in the radial direction between the elastic ring 7c and the main pipe 2, so the piston 7 slides smoothly without any wobbling. move.

〔Effect of the invention〕

As described above, this invention provides a support arm at the lower end of the main pipe of the front fork, and supports the other end of the swinging arm that supports the front wheel at one end rotatably on the support arm. A piston and a swinging arm are connected by a rod, and the piston is spring-loaded downward by a spring. A bush is formed of an elastic body that allows the piston and the rod to slide into the lower end of the main pipe of the front fork, and a spring that holds this bush on the axis of the main pipe is provided. The rod connecting portion of the swinging arm is positioned closer to the center of swing than the connecting portion of the front wheel, so that the vertical movement of the swinging arm is caused by the piston rod. It is allowed by the tilting of Therefore, there is no need to prepare a cylinder separately from the main pipe as in the past, which not only simplifies the structure but also greatly reduces the weight of the vehicle. Further, by attaching the support member to the main pipe, the rod is positioned on the axis of the main pipe by the support member, so that the ease of assembling the rod to the main pipe is improved.

Furthermore, the connection part with the rod in the swinging arm,
Since it is located closer to the center of swing than the connecting portion of the front wheels, it is possible to increase the vertical stroke of the front wheels while reducing the amount of longitudinal tilting of the rod and the amount of sliding of the piston. Therefore, the load applied to the piston when the front wheel moves up and down can be reduced, making the piston less likely to deteriorate and increasing durability.

[Brief explanation of the drawing]

The drawings show one embodiment of the invention.
The figure is a front view of the motorcycle, FIG. 2 is a sectional view thereof, and FIG. 3 is a sectional view thereof. 1...Front fork, 2...Main pipe 2, 4...Support arm, 5
...Swinging arm, 7...Piston, 7a, 7b...Washer, 7
c...Elastic ring, 8...Spring, 9...Piston rod, 9
a...Bracket.

Claims (1)

[Claims] 1 A support arm is provided at the lower end of the main pipe of the front fork,
The other end of a swinging arm that supports a front wheel at one end is rotatably supported by the support arm, and the swinging arm is connected with a rod to a piston that is slidably provided in the main pipe. The piston is formed of an elastic body that slides on the inner surface of the main pipe and allows the rod to tilt due to its elastic deformation, and the rod is attached to the lower end of the main pipe of the front fork. The piston and the rod are swingably supported with respect to the main pipe by providing a bush into which the piston and the rod are slidably fitted and a spring that holds the bush on the axis of the main pipe. A front wheel suspension system for a motorcycle, characterized in that a connecting portion is positioned closer to the center of swing than the connecting portion of the front wheel.