JPS6353076B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a rear wheel shock absorber for a motorcycle, and in particular to a so-called monoshock shock absorber in which a single shock absorber is provided between a rear arm supporting the rear wheel and a vehicle body frame. This is related to the improvement of

Conventionally, a monoshock-type shock absorber, as shown in Japanese Patent Application Laid-Open No. 55-15312, typically extends upward from the front part of the rear arm and is connected to the vehicle body frame below the passenger's seat. It occupies a large space in the front and back directions in the central part of the car. As a result, the space under the vehicle body frame below the seat became narrow, and flexibility in design was often impaired, such as the lack of space to accommodate large parts such as storage batteries and other electrical components, or large parts such as air cleaners, which would normally be placed there. .

This invention was made to eliminate the above-mentioned problems, and is characterized in that the shock absorber is installed with the longitudinal direction of the shock absorber facing in the left-right direction of the vehicle body frame.

The present invention will be explained below with reference to illustrated embodiments. In the figure, 1 is a body frame of a motorcycle, which is constructed by connecting a steering shaft tube 2 at the front end and a bracket 3 at the rear with tube members 4, 4 made of extruded aluminum alloy and having a square cross section. . 4a is a cross member that connects the pipe members 4, 4. A front fork 6 having a front wheel 5 at its lower end is rotatably supported on the steering shaft tube 2 so as to be able to turn left and right, and a rear arm 8 having a rear wheel 7 is supported on the bracket 3 so as to be able to swing vertically by means of a pivot shaft 9. It is pivoted. 11 is an engine cooling radiator provided at the front of the vehicle body frame 1; 12 is a water-cooled V-type engine suspended on the lower surface of the vehicle body frame 1; A carburetor 14 is arranged in between, and exhaust pipes 15, 15 are connected from each cylinder 13, 13.
is derived and extends backward. 16 is a gear box located at the rear of the cylinder and made integrally with the crank chamber; 17 is a sprocket provided on the output shaft, which drives a driven sprocket 19 of the rear wheel 7 via a chain 18. 21 is a fuel tank installed on the upper part of the vehicle body frame 1, and 22 is a seat for a passenger.

The shock absorbing device provided between the vehicle body frame 1 and the rear arm 8 is constructed as follows. That is, 23 is a conventionally known shock absorber consisting of a coil spring with a hydraulic damper, and both ends of the shock absorber are connected via a link 24 and a turnbuckle-shaped rod 25 which are pivotally supported by the aluminum alloy tube members 4, 4, respectively. A bracket 8 protruding from the rear arm 8
connected to a. The link 24 is shown in FIG.
As shown in FIG. 5, an upper arm 28a is connected to an upper end of a support shaft 28 which is supported by a bearing tube 26 welded to the tube members 4, 4 via ball bearings 27, and an upper arm 28a is connected to a lower end thereof. and a lower arm 28b, and the upper arm 28a is connected to the rod 25 via a ball joint 29.
The other end of the rod 25 is connected to a similar ball joint 3.
0 to the bracket 8a. Further, the lower arm 28b is connected to the shock absorber 23 via a pin 31. The shock absorber 23 is thus compressed between the links 24 and 24, and presses the rear arm 8 downward via the rod 25. The cross member 4a also has the function of preventing the gap between the left and right pipe members 4 from expanding due to the spring force of the shock absorber, and is preferably provided close to the shock absorber.

Next, the operation of the embodiment will be described. When the motorcycle is running and the rear wheel 7 passes over a protrusion on the road surface, the rear arm 8 swings upward, and the left and right rods 25, 25 move toward the shock absorber 23. The shock absorber 23 is compressed by compressive force from both sides at the same time and contracts twice as long as the operating stroke of each individual link, so the shock absorber spring is set to be relatively soft. Also, a relatively large vibration damping force can be obtained. Note that the present invention is not limited to the above-described embodiments, and as shown in FIG.
This concept also includes one end of which is rotatably fixed to the vehicle body frame 1 with a pin 32.

As described above, in this invention, the shock absorber is installed in the vehicle body frame with the longitudinal direction facing the left and right direction of the vehicle body frame, and one operating end of the shock absorber is connected to the rear arm via a link mechanism. Compared to the conventionally known system in which the front and rear walls extend longitudinally through the center of the vehicle body frame, a larger space can be obtained within the vehicle body frame, making it easier to accommodate large components such as an air cleaner and a storage battery. Furthermore, since the buffer occupies a small space in the vertical and longitudinal directions, the installation location can be easily selected and the intended purpose can be achieved.

As a result of the above, the end portion of the shock absorber may protrude in the left-right direction of the vehicle body, but this position is generally a dead space and does not cause any particular technical problem.

Furthermore, if the shock absorber is placed directly above the transmission as in the example, the heavy shock absorber will be placed at the lower center of the vehicle body, lowering the center of gravity and being closer to the center of gravity, making it easier to move when turning. The vehicle body can be easily tilted to improve maneuverability, and the rod 25 can also be shortened, making the entire shock absorber smaller and lighter.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a side view of a motorcycle to which the present invention is applied, FIG. 2 is a plan view of the main parts thereof, and FIG.
A plan view corresponding to the figure, Figure 4 is the main part of the link 24
FIG. 5 is an enlarged plan view, and FIG. 5 is a sectional view thereof. DESCRIPTION OF SYMBOLS 1...Vehicle frame, 4...Pipe member, 8...Rear arm, 9...Pivot shaft, 23...Buffer, 24...
...Link, 25...Rotsdo.

Claims (1)

[Claims] 1. In a motorcycle in which the base end of a rear arm that pivotally supports a rear wheel at one end is swingably pivoted to the rear of a vehicle body frame, and a shock absorber is provided between the rear arm and the vehicle body frame, A rear wheel shock absorber is installed on a vehicle body frame so as to face in the left-right direction of the vehicle body frame, and one operating end of the shock absorber is connected to a rear arm via a link mechanism.