JPH0746627Y2 - Rear wheel suspension system for motorcycles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a rear wheel suspension system of a motorcycle having a single rear suspension system.

[Prior Art] Conventionally, as a rear wheel suspension device, a so-called one-piece suspension system in which the center of gravity of the vehicle body is located closer to the center by bringing one heavy rear suspension device closer to the center of the vehicle body Some have a device (for example,
(See JP-A-58-194985 and JP-A-63-11294). FIG. 5 shows an example of the basic configuration of a rear wheel suspension system having this type of single suspension system.

In FIG. 5, reference numeral 1 is a main pipe of a motorcycle, and a body frame 2 is welded to its rear end 1a. 3 is a swing arm whose pivot shaft 23 is the body frame 2
It is rotatably provided to support the rear wheel 4, and a link mechanism 5 is provided between the bracket 3a and the vehicle body frame 2. 6 is a rear suspension device (hereinafter,
Simply called suspension. ), A coil spring and a shock absorber (not shown) are provided, and the fulcrum shaft at the lower end thereof is provided.
67 is attached to the tip of the arm 7 of the link mechanism 5,
On the other hand, a fulcrum shaft 26 at its upper end is attached to the vehicle body frame 2. The vertical movement of the swing arm 3 around the pivot shaft 23 is buffered by the suspension 6 via the link mechanism 5. The swing arm 3 and the link mechanism 5 are provided in a pair on the left and right, and the suspension 6 is disposed between them to form a one-piece suspension device.

[Problems to be solved by the invention] Most motorcycles equipped with such a single suspension device are of a sporty type. There is a problem that we want to obtain a deep bank angle on a curve by changing the vehicle height to suit our taste.

The present invention has been made in view of the above problems, and a rear wheel suspension device for a motorcycle capable of effectively using a free space below a swing arm to perform stepless adjustment of a vehicle height with good workability. Is intended to provide.

[Means for Solving the Problems]

In order to achieve the above object, a rear wheel suspension system of a motorcycle according to the present invention is provided with a link mechanism between a swing arm supporting a rear wheel and a vehicle body frame, and a one-piece rear suspension system is provided. The rear wheel of the motorcycle, which is mounted between the link mechanism and the vehicle body frame via the fulcrum shafts at the upper and lower ends thereof and buffers the vertical movement of the swing arm by the rear suspension device via the link mechanism. A suspension device, wherein a fulcrum shaft that connects a link adjacent to the swing arm of the link mechanism to the swing arm is swingable, and the fulcrum shaft is rotatable in a state in which the axes thereof are displaced from each other. It has a cylindrical eccentric sleeve which is axially supported, a sleeve hole through which the eccentric sleeve penetrates, and a slitting portion, and is fixed to the swing arm. An outer periphery of an end portion of the eccentric sleeve that laterally protrudes from the holder, and a fastening member that narrows the slotted portion and tightens the outer periphery of the eccentric sleeve at the inner peripheral surface of the sleeve hole. Is formed with a tool engaging recess.

[Action]

According to this invention, the fulcrum shaft that oscillates one of the links of the link mechanism to the swing arm is rotatably supported through the eccentric sleeve whose axial center is displaced. Therefore, by rotating the eccentric sleeve, the height of the fulcrum shaft can be changed and the swing arm can be moved up and down, which changes the vehicle height.

Here, it is conceivable to provide an eccentric shaft as described in the above-mentioned prior art on the fulcrum shaft, but this cannot change the vehicle height steplessly. On the other hand, in this invention, the eccentric sleeve rotatably supporting the fulcrum shaft is formed into a cylindrical shape, and the cylindrical eccentric sleeve is penetrated into the sleeve hole having a circular cross section of the holder.
It is possible to change the position of the fulcrum shaft by any amount by loosening the tightening of the holder and rotating the eccentric sleeve by any angle.Therefore, the swing arm moves up and down by any amount to increase the vehicle height. It can be adjusted steplessly. In addition, in such a vehicle height adjustment operation, the empty space below the swing arm is effectively used,
The tool can be easily engaged with the engaging recess formed on the outer periphery of the end portion of the eccentric sleeve, and the workability of adjustment can be improved.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a swing arm 3, an arm 7 and a rod 8 are provided as a pair on the left and right, and a rotatable pivot shaft 23 is provided.
And fulcrum shafts 38, 78, 27 are connected. The pair of swing arms 3 are integrally fixed to each other via a cross member 9.

A holder 10 is welded to the lower surface of the cross member 9. As shown in FIG. 2, the holder 10 is provided with a sleeve hole 10a having a circular cross section and a slit portion 10b in a penetrating state in the left-right direction of the vehicle body.

A cylindrical eccentric sleeve 11 passes through the sleeve hole 10a. The eccentric sleeve 11 has a through hole 11a centered on a position P slightly deviated from its axis 0,
Through this through hole 11a, the needle bearing 12 and the cylinder 13
The fulcrum shaft 38 is supported via. That is, the eccentric sleeve 11 has the axes 0, P of the eccentric sleeve 11 and the fulcrum shaft 38.
Fulcrum shaft 38 is pivotally supported in a state where they are displaced from each other. The holder of FIG. 3 on the outer circumference of the eccentric sleeve 11.
At the end 11b protruding from 10, the tool engagement recess 11c,
It is formed in several places as shown in FIG.

14 is a fastening member composed of a bolt, and the bolt hole 10 of the holder 10 is
The outer peripheral surface of the eccentric sleeve 11 is tightened by the inner peripheral surface of the sleeve hole 10a of the holder 10 by penetrating c and screwing it into the female screw 10d of the holder 10 to narrow the slit portion 10b. It is a thing. Two fastening members 14 are provided on the left and right.

In FIG. 3, the fulcrum shaft 38 is made of long bolts,
One end of one rod 8 is fastened between the head portion 38a and the cylinder 13, and one end of the other rod (not shown) is fastened and fixed by a nut (not shown). Therefore,
The fulcrum shaft 38 swingably connects the rod 8 to the swing arm 3 shown in FIG. That is, the fulcrum axis 38
In the link mechanism 5, a link 8 adjacent to the swing arm 3 is swingably connected to the swing arm 3.

Incidentally, 15 in FIG. 3 is an oil seal. The other structure is similar to that of FIG. 1, and the same portions or corresponding portions are denoted by the same reference numerals and detailed description thereof will be omitted.

Next, the height adjustment of the vehicle height will be described. First, the second
By loosening the fastening member 14 as shown in FIG. 4,
The slot 10b of the holder 10 expands slightly. As a result, the eccentric sleeve 11 becomes rotatable with respect to the holder 10.
Then, the tool 100 is engaged with the engaging recess 11c formed on the outer periphery of the end of the eccentric sleeve 11 from the empty space below the swing arm 3 to rotate the eccentric sleeve 11 by an arbitrary angle. As a result, the shaft center P of the fulcrum shaft 38 rotates around the shaft center 0 of the eccentric sleeve 11, the position of the fulcrum shaft 38 is displaced, and the swing arm 3 in FIG. 1 rotates slightly upward or downward. To do. By the vertical movement of the swing arm 3, the rear wheel 4 is displaced downward or upward, and the vehicle height is changed.

In the above-mentioned structure, the present invention has a cylindrical eccentric sleeve 11 shown in FIG.
The eccentric sleeve 11 can be rotated by an arbitrary angle by loosening the tightening force of the holder 10. Therefore, the swing arm 3 shown in FIG. 1 can be moved up and down by an arbitrary amount, so that the vehicle height changes steplessly.

By the way, in the present invention, the fulcrum shaft 38 connecting the swing arm 3 and the rod 8 is provided with the eccentric mechanism, but it is conceivable to provide the other fulcrum shafts 26, 67, 78, 27 with the eccentric mechanism. , Japanese Utility Model Publication No. 63-11294). However, if the fulcrum shaft 26 is provided with an eccentric mechanism, the fulcrum shaft 26 is located inside the vehicle body, and it becomes difficult to adjust the vehicle height.
Further, if an eccentric mechanism is provided on the fulcrum shaft 27 or 67, the length of the suspension 6 changes, and the suspension characteristics change greatly. When an eccentric mechanism is provided on the fulcrum shaft 78, the moment arm between the fulcrum shafts 27 and 78 is short, and a slight displacement of the fulcrum shaft 78 causes a large change in the position of the fulcrum shaft 67. Will change significantly.

On the other hand, in this invention, since the eccentric mechanism is provided on the fulcrum shaft 38 that is relatively exposed to the outside, the vehicle height adjusting operation is easy. Moreover, since the fulcrum shaft 38 is distant from the pivot shaft 23 and the moment arm between the pivot shaft 23 and the fulcrum shaft 38 is long, the change in the moment arm due to the displacement of the fulcrum shaft 38 is small, so that the suspension characteristic is greatly changed. Never.

As described above, according to the present invention, the eccentric sleeve that rotatably supports the fulcrum shaft is formed in a cylindrical shape, and the cylindrical eccentric sleeve is used for the sleeve having a circular cross section of the holder. Since the hole is penetrated, the vehicle height can be continuously changed by the rotation of the eccentric sleeve. Further, since the eccentric mechanism is provided on the fulcrum shaft that swingably connects the link adjacent to the swing arm and the swing arm, the vehicle height can be easily adjusted and the suspension characteristics can be changed very easily. Therefore, it is possible to ensure a predetermined suspension function regardless of the vehicle height. Moreover, since the recess for engaging the tool is formed on the outer periphery of the end of the eccentric sleeve protruding from the holder, the tool can be easily engaged in the recess by effectively utilizing the empty space below the swing arm. Therefore, there is an effect that the workability at the time of continuously adjusting the vehicle height can be improved.

[Brief description of drawings]

FIG. 1 is a side view of a rear wheel suspension system showing an embodiment of the present invention, FIG. 2 is a sectional view of an eccentric mechanism, and FIG. 3 is III- of FIG.
A sectional view taken along line III, FIG. 4 is a side view showing a method for adjusting the vehicle height, and FIG. 5 is a side view of a general rear wheel suspension system. 2 ... Body frame, 3 ... Swing arm, 4 ... Rear wheel, 5 ... Link mechanism, 6 ... Single rear suspension device, 8 ... Rod (adjacent link), 10 ... Holder, 10a …… Sleeve hole, 10b …… Slitting part, 11 ……
Eccentric sleeve, 14 ...... Fastening member, 26,67,38 …… Support shaft,
0: eccentric sleeve shaft center, P: fulcrum shaft shaft center.

Claims (1)

[Scope of utility model registration request] 1. A link mechanism is provided between a swing arm supporting a rear wheel and a vehicle body frame, and a single-type rear suspension device connects the link mechanism and the vehicle body frame via fulcrum shafts at upper and lower ends thereof. A rear wheel suspension device for a motorcycle, mounted between the two, for damping vertical movement of the swing arm by the rear suspension device via the link mechanism, the link being adjacent to the swing arm of the link mechanism. A fulcrum shaft for swingably connecting to the swing arm, a cylindrical eccentric sleeve rotatably rotatably supporting the fulcrum shaft with their axes displaced from each other, and a circular cross section through which the eccentric sleeve passes. A holder having a sleeve hole and a slotted portion and fixed to the swing arm, and an inner circumference of the sleeve hole by narrowing the slotted portion. A fastening member for tightening the outer circumference of the eccentric sleeve with a surface, and a tool engaging recess is formed on the outer circumference of the end of the eccentric sleeve projecting laterally from the holder. Rear wheel suspension.