JPH0142876B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rear wheel suspension system for a motorcycle having a rear arm having a substantially triangular side surface.

2. Description of the Related Art Conventionally, there has been a motorcycle in which a front end of a rear arm having a generally triangular side surface is pivotally supported on a main frame, and a rear wheel attached to the rear end of the rear arm is held movably up and down. Since such a rear arm has high rigidity, it can reduce twisting of the rear wheel relative to the main frame and significantly improve driving stability. In this case, the cushion unit is arranged to cross the space surrounded by the engine, rear wheels, and seat, and the front end of the cushion unit is pivoted to the main frame, and the rear end is pivoted to the upper apex of the rear arm. I was wearing it. However, the space surrounded by the engine, rear wheels, and seat, that is, the space above the support shaft where the rear arm is attached to the main frame, is usually used as a storage space for air purifiers, batteries, and other electrical equipment. However, since the cushion unit is disposed across these parts, there is a problem in that the space in which these parts can be accommodated is severely restricted.

This invention was made in view of these circumstances, and despite using a rear arm with a generally triangular side surface that is excellent for improving driving stability, it is difficult to use cushioning in the space surrounded by the engine, rear wheels, and seat. The air purifier,
It is an object of the present invention to provide a rear wheel suspension device for a motorcycle that can be used as a storage space for batteries, electrical components, etc., and is also advantageous in terms of frame strength.

According to the present invention, this object is achieved by providing a motorcycle in which a rear wheel is held at the rear end of a rear arm having a substantially triangular side surface, including a cushion unit disposed above the rear wheel substantially parallel to the seat rail, and The front end of the cushion unit is pivoted to the seat rail, and the rear end is pivoted to an arm swingably suspended from the seat rail, and the front end of a link extending forward from the lower end of the arm is connected to the upper apex of the rear arm. This is achieved by a rear wheel suspension system for a motorcycle characterized by the following.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is a side view showing an embodiment of the present invention, and FIG. 2 is a sectional view thereof taken along the line -1. In FIG. 1, reference numeral 10 indicates a main frame, and this main frame 10 includes a steering head pipe 12.
, a pair of left and right down tubes 14 (only one shown), a tank rail 16, a pair of left and right seat rails 18, 18A, 18B, and a pair of left and right backstays 20 (only one shown). The front end of the seat rail 18 is welded to the tank rail 16 and extends rearward. The lower end of the backstay 20 is connected to the rear end of the down tube 14 and the tank rail 16.
It is fixed to the rear end by a bracket 22, and the upper end of this back stay 20 is connected to the seat rail 18.
It is welded near the center of the. 24 is an engine, which is mounted between the down tube 14 and the tank rail 16.

26 is a rear arm having a substantially triangular side surface, and the front end of this rear arm 26 is connected to the main frame 10.
It is connected to the bracket 22 by a support shaft 28 so as to be able to swing vertically, and a rear wheel 30 is held at the rear end.

32, 32A, 32B are a pair of left and right cushion units, and each seat rail 18A,
It is disposed approximately parallel to the seat rails 18A and 18B so as to be located outside of the seat rails 18B and above the rear wheels 30. This cushion unit 32A, 32
The front end of B is the seat rail 18 and backstay 20
It is pivoted to a bracket 34 (there is a pair of left and right, but only one is shown) that is welded to the joint of the seat rails 18A and 18B, and its rear end is pivoted to an arm 36 that is swingably suspended from between the seat rails 18A and 18B. . That is, as shown in FIG. 2, a bracket 38 is stretched between the seat rails 18A and 18B, and an arm 36 is suspended from this bracket 38, while both ends of a shaft 40 passing through the lower end of this arm 36 are connected to a cushion. It is connected to the rear ends of units 32A and 32B. The lower end of the arm 36 is formed into a bifurcated shape, and the shaft 40 passes through this bifurcated portion.
Reference numeral 42 denotes a link, one end of which is connected to the lower end of the arm 36 by a shaft 40, and the other end connected to the upper apex 44 of the rear arm 26. In Figures 1 and 2, 46 is a tandem seat installed above the seat rail 18;
is a rear fender installed above the rear wheel 30,
Further, in FIG. 1, 50 is a fuel tank, 52 is a front fork, 54 is a front wheel, and 56 is a handlebar.

Next, the operation of this embodiment will be explained. If the rear wheel 30 moves upward from the state shown in FIG. 1, the rear arm 26 rotates counterclockwise about the support shaft 28.
Along with this, the upper apex 44 of the rear arm 26 also rotates in the same direction around the support shaft 28, so that the link 4
2 is pulled to the left in Figure 1. Therefore, the arm 36 rotates clockwise about its upper end together with the shaft 40, and the cushion units 32A and 32B connected to both ends of the shaft 40 are simultaneously compressed.
The cushion units 32A, 32B are disposed substantially parallel to the seat rail 18, and the reaction force thereof applies a force in a tensile direction to the seat rail 18, so that the seat rail 18 is advantageous in terms of strength. Therefore, the frame can have sufficient strength with structural members of approximately the same level as conventional ones, and the weight of the vehicle body does not increase due to the application of the present invention.

In this embodiment, the cushion unit 32 is disposed outside the seat rail 18, so that the cushion unit 32 is easily exposed to the traveling wind, and the cushion unit 32 has the effect of improving its cooling performance.

FIG. 3 is a cross-sectional view of another embodiment taken at a position corresponding to the - line, and in this embodiment two cushion units 32A and 32B are connected to the seat rail 1.
It is arranged inside 8A and 18B. In this figure, the same parts as in FIG. 2 are given the same reference numerals, so the description thereof will not be repeated.

According to the embodiment of FIG. 3, the seat rail 1
By effectively utilizing the space between 8A and 18B, the rear wheel suspension system can be housed in a compact manner, and the vertical movement range (wheel travel) of the rear wheels can be increased.

FIG. 4 is a side view showing still another embodiment, and FIG.
The figure is a sectional view taken along the - line. In this embodiment, one cushion unit 60 is provided between a pair of left and right seat rails 18A, 18B, and the front end of this cushion unit 60 is connected to a pair of left and right brackets 34.
The rear end of the rear arm 62 is pivoted near the center of the arm 62, and the lower end of the arm 62 and the upper apex 44 of the rear arm 26 are connected by a link 36.

As described above, this invention has a cushion unit disposed above the rear wheel substantially parallel to the seat rail,
Its front end is pivoted to the seat rail, and its rear end is pivoted to an arm suspended from the seat rail, and the front end of a ring extending forward from the lower end of this arm is connected to the upper apex of the rear arm, so that the cushion unit is connected to the engine. It is no longer necessary to pass through the space surrounded by the rear wheels and the seat, and this space can be secured, and the air purifier can be placed here.
It becomes possible to accommodate batteries, electrical components, etc. with sufficient room. Further, since the reaction force of the cushion unit is applied to the seat rail in the tensile direction, the seat rail becomes advantageous in terms of strength. Therefore, the reinforcing members for the frame need only be of approximately the same level as conventional ones, and the overall weight of the frame does not increase.

[Brief explanation of drawings]

Fig. 1 is a side view showing one embodiment of the present invention, Fig. 2 is a sectional view taken along the - line, Fig. 3 is a sectional view corresponding to the - line showing another embodiment, and Fig. 4 is a sectional view corresponding to the - line showing another embodiment. FIG. 5 is a side view showing an example, and FIG. 5 is a sectional view taken along the - line. 18... Seat rail, 26... Rear arm,
30... Rear wheel, 32, 60... Cushion unit, 36, 62... Arm, 42... Link, 4
4... Upper vertex.

Claims (1)

[Claims] 1. A motorcycle in which a rear wheel is held at the rear end of a rear arm having a substantially triangular side surface, including a cushion unit disposed above the rear wheel substantially parallel to the seat rail, and the front end of the cushion unit is connected to the seat rail. The motorcycle further comprises a rear end pivotally attached to an arm swingably suspended from the seat rail, and a front end of a link extending forward from the lower end of the arm connected to an upper apex of the rear arm. rear wheel suspension.