JPS6012793Y2 - Rear wheel suspension system for motorcycles - Google Patents

Description

[Detailed explanation of the invention] This invention is an automatic automatic transmission system that allows for a large cushion stroke to increase shock absorption performance, and also ensures sufficient space in the center of the vehicle body. This invention relates to a rear wheel suspension system for a two-wheeled vehicle.

The rear wheel suspension system of a motorcycle has its front end pivoted to the vehicle body frame, and a cushion unit is installed between a part of the swing arm, which has an axle attached to its rear end, and the top of the vehicle body frame. Usually, the vibration is received by a cushion unit and the shock is absorbed.

In the case of such a structure, there is no problem in general use, but when trying to increase shock absorption performance by increasing the cushion stroke, or changing from a two-seater specification to a one-seater specification. There are various inconveniences when trying to change the spring to a weaker one.

In order to solve this problem, a locking arm whose middle part is pivotally connected to a shaft and rotates is provided above the swing arm pivot point of the vehicle body frame, and the front end of this locking arm and the swing arm are connected to the vehicle body frame. A cushion unit consisting of a coil spring and a damper inserted between the coil spring and the part near the pivot joint is installed, and the rear end of the rocking arm and the part near the rear axle mounting part of the swing arm are connected by a rod. It is possible to do so.

With this configuration, it is possible to increase the shock absorption performance by increasing the cushion stroke, but the space in the center of the car body becomes narrower due to the provision of the cushion unit, and the volume of the air cleaner etc. is increased. This results in the problem that it is not possible to do so.

The purpose of the present invention is to solve the above-mentioned problems.The features of the present invention include separating a cylinder part and a spring part constituting a cushion unit, attaching the spring part to a pivoting part of an arm, Only a damper is installed between the front end of the rocking arm and the part near the pivot point of the swing arm to the vehicle body frame.
This improves shock absorption performance and also secures space in the center of the vehicle body.

Hereinafter, embodiments of the present invention will be described based on the drawings.

In FIGS. 1 and 2, 1 is a vehicle body frame,
Although not shown, a seat is attached to the top and an engine is attached to the front.

A bracket 3 is attached to the lower part of a pair of frame pipes 2 constituting a part of the vehicle body frame 1, and a front end of a swing arm 4 is pivotally attached to this bracket 3 by a shaft 5.

A hole 6 is provided at the rear end of the swing arm 4, to which a rear wheel (not shown) is attached.

The pair of frame pipes 2 face each other with a gap between them, and a locking arm 8 whose intermediate portion is pivotally connected by a shaft 7 is located above the pivoting portion of the swing arm 4 of the frame pipes 2, 2. It is provided.

The middle part of the locking arm 8 is composed of a pipe 9 rotatably inserted into the shaft 7, and a pair of arm parts 10.1 facing each other are provided at both ends of the pipe 9.
0 is attached by welding etc., and the locking arm 8
is composed of

A spring, which is a component of the cushion unit, ie, a coil spring 11 is wound around this pipe 9 in the axial direction of the shaft 7. One end of this coil spring 11 is attached to one of the pair of frame pipes 2. .

The other end of this coil spring 11 is attached to an arm portion 10 close to the other of the pair of frame pipes 2,
A spring force is applied to the locking arm 8 in the torsional direction of the coil spring 11.

Arm portion 10.1 forming part of the locking arm 8
A damper 12 which is one component of the cushion unit, that is, an upper end 12a of the cylinder portion is pivotally attached to the front end of the cushion unit 0 by a shaft 13.

The lower end of the damper 12 is pivotally connected to a portion of the swing arm 4 near the pivot point to the frame pipe 2 by a shaft 14.

The rear end of the arm portion 1o constituting a part of the locking arm 8 and a portion near the rear axle attachment portion of the swing arm 4 are attached by a rod 15.

In this rear wheel suspension system configured in this way, when the rear end of the swing arm 4 rises as the motorcycle travels, this movement is transmitted to the damper 12 and the coil spring 11 via the rod 15 and the locking arm 8. As a result, the damper 12 is compressed, and a reaction force is generated in the coil spring 11 in a direction that causes the rear end of the swing arm 4 to move downward.

In this way, the impact caused by the movement of the swing arm 4 is absorbed by the damper 12, which has a cushioning function, and the coil spring 11.
It will be absorbed by.

In this case, since the lower end of the damper 12 is pivotally attached to the front part of the swing arm 4, a large cushion stroke can be achieved.

Since the present invention is configured as explained above, it has the following effects.

(1) Since the lower end of the tamper is pivotally connected to the front part of the swing arm so that a large cushion stroke can be taken, shock absorption performance can be increased.

(2) Since the coil spring, which has a cushioning function, is wound in the axial direction of the shaft, a large space can be secured in the center of the vehicle body, and the volume of the air cleaner etc. can be increased.

(3) By removing the coil spring from the damper, the wheelbase can be shortened, which reduces weight and allows the motorcycle to be made more compact.

(4) The coil spring can be manufactured without considering the relationship with the damper, making it easy to manufacture the coil spring.

(5) Since a large space can be secured in the center of the vehicle body, design becomes easier.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a main part of an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line A--A in FIG. 2...Frame pipe, 4...Swing arm, 7...Shaft (pivot part of arm), 8...Rocking arm, 10...・・・
・Arm part, 11...◆...Coil spring (spring), 12...Damper (part of cylinder).

Claims (1)

[Scope of utility model registration request] A locking arm whose intermediate portion is pivotally connected and rotates is provided above the swing arm pivot portion of the vehicle body frame, and a front end of the locking arm and a portion of the swing arm near the pivot portion to the vehicle body frame are connected. A part of the cylinder of the cushion unit, which is separated into a part of the cylinder and a spring part which is a coil spring, is attached between the parts, and the rear end of the rocking arm and the part near the rear axle attachment part of the swing arm are connected by a rod. The spring portion, which is the coil spring, is wound around the pipe of the rocking arm portion so as to apply an acting force to the rocking arm in the same direction as that of a portion of the cylinder of the cushion unit, and one end of the spring portion is wound around the pipe of the rocking arm portion. A rear wheel suspension device for a motorcycle, characterized in that a rear wheel suspension device for a motorcycle is secured to a frame, and the other end is locked to an arm portion of a tanking arm.