JPS61178281A - Shock absorber for rear wheel of cycle car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field] The present invention can provide an effective auxiliary equipment storage space within the vehicle body frame, lower the center of gravity, and solve problems [Problems with the prior art] The rear wheels are supported at the rear end. The front end of the swing arm is pivoted to the rear end of the vehicle body frame so that it can swing up and down, and the swing arm and shock absorber are rotatably connected via a link and a bell crank. Progressive rear wheel suspensions are already known, which compress the shock absorbers while progressively increasing the associated load.

Since such a shock absorber is arranged vertically running through the center of the vehicle body, auxiliary equipment interposed at this position, such as an air cleaner, intake manifold hole F1 exhaust pipe, etc.
Because of this, the degree of freedom in mounting layout is impaired, engine performance is reduced, and maintenance is also inconvenient.

Furthermore, since the lower end of the shock absorber is provided near the pivot portion of the swing arm, a large bending moment is applied to the swing arm, and in order to resist this, strength and rigidity must be improved, resulting in an increase in the size of the swing arm. In addition, the layout of the shock absorber as described above raises the center of gravity of the vehicle, resulting in unstable handling during cornering, and improvements are desired.

[Purpose of the invention]

SUMMARY OF THE INVENTION In view of the problems of such three-wheeled motor vehicles for traveling on rough terrain (hereinafter referred to as automatic three-wheeled vehicles), it is an object of the present invention to provide specific structural means for effectively solving the problems.

In order to achieve the above object, the present invention has one shock absorber tilted forward and its rear end pivoted to the rear end of the swing arm, the front end of which is connected to the upper end of the link pivoted to the cross member. The gist is that a progressive link mechanism is created by connecting the links and providing a telescopic tension rod between the links and the vehicle body frame.

[Structure and Examples]

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a rear side view of a tricycle to which the rear wheel shock absorber according to the present invention is applied, FIG. 2 is a plan view thereof, and FIG. 3 is an explanatory schematic side view showing the operating characteristics of this rear wheel shock absorber. It is a diagram.

As shown in FIGS. 1 and 2, a body frame 1 includes a down tube 3 and a bottom frame 4 that extend downwardly from a head pipe 2, a main frame 5, and a seat rail that extends one rearward and has a passenger seat 6. 7, and a center frame 8 that vertically connects the bottom frame 4 and the main frame 5, and a sub-frame 11 serving as a reinforcing member is connected to the center frame 8 diagonally forward from the rear of the seat rail 7.

The front end of a swing arm 10 is pivotally attached to the center frame 8 so as to be able to swing vertically around a pivot shaft 9, and a cylindrical bearing 12 is integrally connected to the rear end of the swing arm 10 via an inner bearing 13, 14. The rear two-wheel Wr+ is equipped with balloon tires on both ends.

A single driven shaft 15 to which Wr2 is attached is rotatably supported, and a crossmen/(-16) is installed across the violet in front.

The rear frame 17 has a substantially dogleg shape and is connected to the rear of the center frame 8 with its protruding portion facing rearward. and join them together.

On the other hand, a link 20 is pivotally mounted on the cross member 16 via a support shaft 19, and a buffer 25 is connected between the top of the link 20 and the bearing 12 by support shafts 23 and 24. It is placed leaning forward.

Between the support shafts 19 and 23 on the link 20 and between the bracket 22 on the cross pipe 18, ball joints 27 and 28 are provided at both ends, and a screw 29 and a nut 3 are provided.
Tension rods 31 and 32, whose lengths can be freely adjusted by screwing them together, are pivotally connected by support shafts 33 and 34, respectively.

This relationship is as shown in FIG. 3(a), where the support shaft 34 is at point b, the support shaft 33 is at point a, and the support shaft 23 is at point 0 (a, b).

By setting C to an acute angle when no load is applied, the upward movement of the swing arm 10 accelerates the shock absorber as shown in (b) (as a, b, and c approach a right angle, the synergistic effect with the lever ratio of the link 20 25 can be compressed to a large extent, thereby increasing the elastic force during full flexion and preventing bottoming.

Therefore, in the small swing range of the swing arm, the spring force of the shock absorber 25 is softened, and a strong load is applied, and in the maximum swing range, a 1-degree spring force is obtained. In addition, the above (a,
The angles b' and c can be adjusted to desired values by rotating the nut 30 of the tension rod.

Next, the operation will be explained.

As shown in Figure 1, the rear two wheels Wr1. When a load is applied to Wr2, the swing arm 10 rotates in the anti-needle direction about the pivot shaft 9, and the link 20 also moves upward.

Therefore, the shock absorber 25 is compressed from the rear end in the direction of arrow F1, and as described above, the link 20 is also compressed in the direction of arrow F2 while drawing an arcuate trajectory clockwise around the support shaft 19. Since the action is gradually increased as the swing angle of the swing arm 10 increases, a progressive characteristic is obtained.

When the load decreases, the shock absorber 25 is elastically expanded according to the damping force and returned to the IG state.

Since the shock absorber 25 is compressed from both sides in this way, the load acting on the swing arm 10 and the vehicle body frame 1 is reduced, and the strength of these can be set low. In particular, the swing arm 10 is protected from bending loads from above, front and rear. This results in a compressive load in the direction, and there is no protrusion of the vehicle body frame 1 to improve the riding comfort.

Although two tension rods 31 and 32 are used in the figure, it is clear that they may be used as one or cantilever type for use in a motorcycle.

〔effect〕

As is clear from the above description, according to the present invention, the rear end of one shock absorber is tilted forward and pivotally supported by the rear end bearing of the swing arm, and the progressive link mechanism is interposed in front of this, so that the shock absorber is A larger space can be provided at the top of the device, increasing the degree of freedom in attaching auxiliary equipment, and due to the structure, no bending load is applied to the swing arm, making it possible to reduce the size and weight as well as provide cushioning. It also has a subtle effect on improving the response of the instrument.

Moreover, since the shock absorber stroke is set longer depending on the link lever ratio, the width of the shock absorber's adjustment range is increased, the desired shock absorbing performance can be obtained, and the center of gravity can be lowered.These features improve driving performance. Since it is stable, it is ideal as a rear wheel shock absorber for tricycles.

[Brief explanation of drawings]

Fig. 1 is a side view of essential parts of a tricycle to which the rear wheel shock absorber according to the present invention is applied, Fig. 21 is a plan view thereof, and Fig. 3 is an explanatory outline showing the operating characteristics of this rear wheel shock absorber. FIG. In the figure, 1 is a body frame, 3 is a down tube, 8 is a center frame, 17 is a rear frame, 22 is a bracket, 25 is a shock absorber, and 31 and 32 are tension rods.

Claims (1)

[Claims] 1) In a rear wheel shock absorber for a tricycle in which a rear wheel is supported at the rear end of a swing arm, and a shock absorber and a link mechanism are disposed between the rear end of the swing arm and the vehicle body frame, the front end of the shock absorber is connected to the swing arm. A three-wheeled motor vehicle, which is supported on the upper end of a link pivotally supported on a cross member, and a telescopic tension rod is rotatably connected between the upper and lower support shafts of the link and the vehicle body frame. Rear wheel shock absorber.