JPH0362592B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rear suspension for a motorcycle equipped with a single buffer spring member.

[Conventional technology]

For example, as a rear suspension for a motorcycle using a single buffer spring member, US Patent No.
There is one disclosed as No. 3907332. This is a link mechanism that transmits power to a rod-shaped link member pivotally attached to the rear arm and an L-shaped link member rotatably attached to both left and right sides of the vehicle body frame, and also restricts the movement of the buffer spring member. The L-shaped link member has the function of transmitting the swinging motion of the rear arm to the buffer spring member and the function of regulating the movement of the buffer spring member with respect to the vehicle body frame.

[Problem to be solved by the invention]

However, with this structure, there was a problem in that the width of the vehicle body frame could not be made narrower to make it more compact. That is, since the swinging motion of the rear arm is transmitted to the buffer spring member via the L-shaped link member pivotally connected to the vehicle body frame, it is necessary to provide this member with sufficient rigidity. This is because the vehicle becomes large and occupies a large storage space on both sides of the vehicle body frame. On the other hand, in the case of motorcycles, it is preferable that the body frame be as small as possible because many parts such as an engine, an air cleaner, and electrical components are accommodated in an extremely limited space.
The present invention was made in view of these circumstances,
To provide a rear suspension for a motorcycle whose body frame can be downsized.

[Means to solve the problem]

The rear suspension according to the present invention has a rotating end side of a connecting rod pivotally connected to a rear arm, and a swinging end side of a swinging link pivotally connected to a cross member connecting left and right vehicle body frame members of a vehicle body frame. A buffer spring member is interposed between the rotating end side of the connecting rod and the vehicle body frame, and the swing link is connected to a connecting rod having a boss portion on the cross member side. It is formed into a bifurcated shape with a pair of left and right boss portions on the sides.

[Effect]

In the present invention, the swinging motion of the rear arm is transmitted to the buffer spring member by the connecting rod, and the movement of the buffer spring member is regulated with respect to the vehicle body frame by the swing link.
Therefore, only a tensile load acts on the swing link, and since it has a bifurcated shape, it can be made smaller.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view showing the rear suspension of a motorcycle according to the present invention, FIG. 2 is an enlarged perspective view showing the main parts, FIG. 3 is an exploded view of the main parts, and FIG.
The figure is a sectional view taken along the line -- in FIG. 3. In FIGS. 1 and 2, the reference numeral 1 indicates the vehicle body frame, and the girder member 3 extends rearward from the steering shaft tube 2 at the front end.
and a main column member 4 extending downward from the rear part of the girder member 3. In this embodiment, the girder member 3 and the main column member 4 are both made of two left and right steel pipes, and the girder member 3 and the main column member 4 are integrally formed by bending these steel pipes. 5
is an auxiliary frame that reinforces the girder member 3 and the main pillar member 4. The lower ends of the main column member 4 and the auxiliary frame 5 are welded to each other by a box body 6 formed of a steel plate, and a rear wheel 8 is supported by a support shaft 7 supported by the box body 6. The base end of the rear arm 9 is swingably supported. 11 is a drive gear case formed at the rear end of the rear arm 9, and 12 is a drive shaft for the rear wheel 8. Above the girder member 3 is a fuel tank 13,
It is covered by the passenger seat 14 and the like. 15
1 is a V-type two-cylinder engine having front and rear cylinders 15A and 15B, 16 is its intake pipe, and 17 is an exhaust pipe.

Reference numeral 18 denotes only one buffer spring member, which is a conventionally known means mainly consisting of a coil spring and a hydraulic damper. The buffer spring member 18 is arranged approximately on the center plane of the vehicle body frame, its front end is supported by the vehicle body frame 1 by a pivot shaft 19, and its rear end is located at the joint between the girder member 3 and the main column member 4, That is, they are connected to a swing link 21 that is pivotally supported near the downward bend of the steel pipe that forms them. A connecting rod 22 is pivotally connected to the rear arm 9 and connects the buffer spring member 18 and the rear arm 9, and the swinging end of the swinging link 21 is pivotally mounted on the swinging end side of the rod so that they are connected to each other. At the same time, the rear end of the buffer spring member 18 is pivotally attached to the rotation end side. In this embodiment, these three members are connected to each other by a single support shaft 25, as will be described later. That is, the swing link 21 and the connecting rod 22 constitute a link mechanism, and the rotating end side of the connecting rod 22 and the vehicle body frame 1
A buffer spring member 18 is interposed between the two. 3 and 4 show the link mechanism connecting the buffer spring member 18 and the rear arm 9 in an expanded manner.

A boss 21A provided at the base end of the swing link 21 is supported by a pin 24B via a rubber bush 23, and swings as the rubber bush 23 is torsionally deformed. The pin 24B is supported via two brackets 24A on a cross member 24 that connects the parts forming the main pillar members 4, 4 of the two left and right steel pipes constituting the vehicle body frame 1. . The other end of the swing link 21 is bifurcated corresponding to the left and right arms of the rear arm 9, and a pair of left and right boss portions 21B, 21B are integrally provided. These boss parts 21B, 2
1B is supported by a support shaft 25 supported at the rotating end of the connecting rod 22, as shown in FIG. 18B
is the rear end of the buffer spring member, and the boss portion 21
It faces between B and 21B and is similarly supported by a support shaft 25 via a rubber bushing 26. Connection rod 22
is made of aluminum alloy by die casting or molten metal forging, and has bifurcated leg portions 22A. Each leg 22A is fitted with a rubber bush 27 at its lower end and is swingably connected by a bolt 28. 29 is a nut welded to the bracket of the rear arm 9.

In the rear suspension of a motorcycle configured in this way, when the rear wheel 8 rides on a convex part on the ground, the rear arm 9 swings upward in FIG. The swing link 21 is moved in the counterclockwise direction. The swing link 21 converts the vertical movement of the connecting rod 22 into a direction along the girder member 3, and presses the rear end of the buffer spring portion 18 forward to compress it. When the rear wheel 8 falls into a depression on the ground, the above operation is performed in the opposite direction, and the vertical movement of the rear wheel 8 is buffered by the expansion and contraction of the buffer spring member 18.

Therefore, the swinging motion of the rear arm 9 can be transmitted to the buffer spring member 18 by the connecting rod 22, and the movement of the buffer spring member 18 can be restricted with respect to the vehicle body frame 1 by the swing link 21. For this reason, the swing link 2
Since only a tensile load can be applied to the swing link 1, the swing link 21 can be made into a simple shape with low rigidity, and the swing link 21 can be made small. Moreover, since the shape of the swinging link 21 is made into two-armed boss portions 21B, 21B corresponding to the left and right arms of the rear arm 9, and a single boss portion 21A pivotally attached to the vehicle body frame 1, the swinging link 21 The size of the link 21 can be reduced compared to a structure in which the link 21 is divided into left and right parts. Furthermore, the main pillar members 4, 4
A swing link 21 is attached to a cross member 24 that connects the
By pivotably mounting the swing link 21, the swing link 21 can be pivotably mounted inside the main pillar members 4, 4.

Therefore, since the swinging link 21, which is made as small as possible, can be arranged inside the main pillar members 4, 4, the main pillar members 4, 4 can be arranged as small as possible. 4 is narrowed in the vehicle width direction, and the body frame 1
can be downsized.

〔Effect of the invention〕

As explained above, according to the present invention, the swinging end side of the connecting rod pivotally connected to the rear arm and the swinging link pivotally connected to the cross member connecting the left and right vehicle body frame members of the vehicle body frame swing. one buffer spring member is interposed between the rotating end side of the connecting rod and the vehicle body frame, and the swinging link has one boss portion on the cross member side. Since it is formed into a bifurcated shape with a pair of left and right boss parts on the connecting rod side, the swing link that forms the link mechanism that supports the rear arm is made so that only a tensile load is applied to it, and its shape is changed to one on the cross member side. By forming the boss part on the boss part and the bifurcated boss part on the connecting rod side, it is possible to reduce the size, and moreover, the swing link can be disposed inside the vehicle body frame.

Therefore, as the swing link is downsized, the vehicle body frame located on both sides of the swing link can be narrowed in the vehicle width direction, and the vehicle body frame can be downsized.

[Brief explanation of drawings]

Fig. 1 is a side view showing the rear suspension of a motorcycle according to the present invention, Fig. 2 is an enlarged perspective view showing the main parts, Fig. 3 is an exploded view of the main parts, and Fig. 4 is the same as Fig. 3. - line sectional view. DESCRIPTION OF SYMBOLS 1...Vehicle frame, 9...Rear arm, 18...Buffer spring member, 21...Swing link, 21A, 21
B...Boss part, 22...Connection rod, 24...Cross member.

Claims (1)

[Claims] 1 A swinging link 21 that is pivotally connected to a cross member 24 that connects the rotating end side of a connecting rod 22 that is pivotally connected to the rear arm 9 and the left and right vehicle body frame members of the vehicle body frame 1.
A buffer spring member 18 is connected between the rotating end of the connecting rod 22 and the vehicle body frame 1.
interposed therein, and the swing link is formed into a bifurcated shape having one boss portion 21A on the cross member 24 side and a pair of left and right boss portions 21B on the connecting rod 22 side. rear suspension.