JPH06294432A - Shock absorber for vehicle - Google Patents

Abstract

(57) [Abstract] [Purpose] The overall length of the shock absorber can be shortened and the weight can be reduced, the suspension stroke can be increased and the unsprung weight can be reduced. A vehicle having a damping cylinder and a piston rod that expands and contracts from the damping cylinder with a damping action, and the damping cylinder and the piston rod are provided with connecting brackets that are respectively connected to a vehicle body or a suspension member. In the shock absorber, the piston rod and the connecting bracket provided on the piston rod side are integrally formed. Further, the piston rod and the connecting bracket provided on the piston rod side are made of a light material such as a light alloy, and the sliding surface of the piston rod is surface-hardened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle shock absorber.

[0002]

2. Description of the Related Art A general shock absorber provided in a vehicle such as a motorcycle includes a damping cylinder, a piston rod which expands and contracts from the damping cylinder with a damping action, and a surrounding of the damping cylinder and the piston rod. And a spring that applies an urging force in a direction in which the piston rod is pulled out from the damping cylinder.

The damping cylinder and piston rod are
Connection brackets are provided respectively, and these connection brackets are respectively connected to a vehicle body (vehicle body frame) or a suspension member.

FIG. 4 shows such a shock absorber 1.
It is a longitudinal cross-sectional view showing one end portion of 00. As shown in this figure, the piston rod 101 and the connecting bracket 102 are fixed by screwing the male screw formed on the end of the piston rod 101 in the related art to the screw formed on the connecting bracket 102. It had a structure that Reference numeral 103 is a spring that extends the shock absorber 100.

[0005]

However, when the piston rod 101 is screwed into the connecting bracket 102 in this way, in order to secure the fixing strength of both members 101, 102, the length L of the threaded portion is increased. Need to take. Therefore, the total length of the shock absorber 100 is increased by the length L of the threaded portion.

Therefore, when the shock absorber 100 is mounted on a vehicle such as a motorcycle having a very limited space inside the vehicle body, the shock absorber 100 is used.
In some cases, the lever ratio of the suspension, that is, the suspension stroke, must be sacrificed in order to avoid interference with the other components. Further, there is a drawback that the weight of the shock absorber 100 increases.

Further, conventionally, the connecting bracket 102
However, since the shock absorber 100 and the piston rod 101 are made of an iron-based material, the total length of the shock absorber 100 is long, which causes an increase in the weight of the shock absorber 100, in particular, an increase in the unsprung weight. However, there are problems such as deterioration of ride quality and deterioration of riding comfort.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to shorten the overall length of the shock absorber and realize weight reduction, and to increase the suspension stroke and reduce the unsprung weight. It is an object of the present invention to provide a shock absorber for a vehicle that can be used.

[0009]

To achieve the above object, a vehicle shock absorber according to the present invention comprises a damping cylinder and a piston rod which expands and contracts from the damping cylinder with a damping action. A shock absorber for a vehicle, in which a connecting bracket connected to a vehicle body or a suspension member is provided on a cylinder and a piston rod, respectively,
The connecting bracket provided on the piston rod side is integrally configured.

The piston rod and the connecting bracket provided on the piston rod side are made of a light material such as a light alloy, and the sliding surface of the piston rod is surface-hardened. It is a thing.

[0011]

According to the shock absorber for a vehicle having the above-mentioned structure, the screw portion for fixing the piston rod and the connecting bracket is not required, so that the overall length of the shock absorber is shortened by the amount of the screw portion. Therefore, even if the lever ratio of the suspension is increased, the shock absorber does not interfere with other parts, and the suspension stroke can be lengthened.

Further, since the piston rod and the connecting bracket which are formed of a light material such as a light alloy are extremely lightweight, the total length of the shock absorber is shortened and the weight of the shock absorber is greatly contributed. be able to. In this case, particularly, the unsprung weight is reduced, so that the road surface followability of the wheel and the riding comfort can be improved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a left side view of a motorcycle showing an example of a vehicle to which the present invention is applied. This motorcycle 1
A front fork assembly 4 supporting a front wheel 3 is pivotally mounted on the front head of the vehicle body frame 2. Also,
A swing arm 7 that supports a rear wheel 6 is pivotally supported on a pivot shaft 5 that is installed in the lower center of the body frame 2 so as to be vertically rotatable, and the rear wheel 6 is driven in front of the pivot shaft 5. An engine 8 is mounted, and a fuel tank 9 is installed above the engine 8. The engine 8 has
An exhaust muffler 11 extending rearward is connected.

A suspension device 12 is provided at the base end of the swing arm 7. This suspension device 12 includes, for example, a shock absorber 13 and a 2
It is composed of individual link members 14 and 15.

The shock absorber 13 has its upper end pivotally attached to the vehicle body frame 2. On the other hand, the link member 14 has one end pivotally attached to the pivot shaft 5 and the other end rotatably connected to the lower end portion of the shock absorber 13. Then, the intermediate portion of the swing arm 7 and the intermediate portion of the link member 14 are connected by the link member 15.

Therefore, the rear wheel 6 is pressed from below,
When the swing arm 7 rotates upward, the link member 15
Pulls the link member 14 upward, and the link member 14 compresses the shock absorber 13. Therefore, the reaction force of the shock absorber 13 is transmitted to the swing arm 7 via the link members 14 and 15, and the swing arm 7 and the rear wheel 6 are pushed back downward.

FIG. 3 is an enlarged view of the shock absorber 13. The shock absorber 13 includes a damping cylinder 16
And a piston rod 17 that expands and contracts from the damping cylinder 16 with a damping action. Damping cylinder 1
A damping damper device (not shown) that operates by utilizing the flow resistance of oil, the compression resistance of gas, and the like is built in 6 and a reservoir tank 18 for replenishing the oil and gas is provided outside the damping cylinder 16. It is provided. 1
Reference numeral 9 is a dial for adjusting the damping force.

The damping cylinder 16 and the piston rod 17 are provided with outer flange-shaped spring receivers 21 and 22, respectively.
A spring 23 is elastically mounted between the first and second parts. Therefore, the urging force of the spring 23 urges the piston rod 17 in the direction of being pulled out from the damping cylinder 16, and the urging force of the spring 23 becomes a reaction force of the shock absorber 13.

At the upper end of the damping cylinder 16, a connecting bracket 24 connected to the vehicle body frame 2 is provided. On the other hand, the piston rod 17 has the link member 1
A connecting bracket 25 connected to the 4 is provided.

FIG. 1 is a vertical sectional view taken along the line II of FIG.
1 shows an embodiment of the present invention. As shown in this figure, the connecting bracket 25 is integrally formed on the extension of the piston rod 17. The spring receiver 22 is annularly mounted on a step portion between the piston rod 17 and the connecting bracket 25 via a washer 26.

Here, the integrated piston rod 17
The connecting bracket 25 is made of a light material such as a light alloy. Also, the sliding surface of the piston rod 1
A surface hardening treatment (for example, hard chrome plating) is applied to 7a.

An inner rod 27 communicating with the damping damper device is inserted through the center of the piston rod 17, and the connecting bracket 25 has the inner rod 2 connected thereto.
An adjusting bolt 28 for adjusting the damping force of the damping damper device by finely moving the position of 7 is provided. One of the adjust bolt 28 and the dial 19 adjusts the damping force on the extension side of the shock absorber 13,
The other is to adjust the damping force on the contraction side.

As described above, when the piston rod 17 and the connecting bracket 25 are integrated with each other, a screw portion for fixing the piston rod 101 and the connecting bracket 102 is unnecessary unlike the conventional shock absorber 100 shown in FIG. become. Therefore, the overall length of the shock absorber 13 is shortened by the length L of the threaded portion, and the shock absorber 1 is reduced even if the lever ratio of the suspension is increased.
There is no possibility that 3 will interfere with other parts such as the exhaust muffler 11. Therefore, the suspension stroke can be lengthened.

Further, since the piston rod 17 and the connecting bracket 25, which are formed of a light material such as a light alloy, are very lightweight, the overall length of the shock absorber 13 is shortened, and the shock absorber 13 is lightened. Can greatly contribute to. In this case, particularly, the unsprung weight is reduced, so that the road followability of the rear wheel 6 of the motorcycle 1 and the riding comfort of the motorcycle 1 can be improved.

The sliding surface 17a of the piston rod 17
Due to the surface hardening treatment applied to the piston, the piston rod 17 that expands and contracts from the damping cylinder 16 is not worn.

[0027]

As described above, the vehicle shock absorber according to the present invention has the damping cylinder and the piston rod that expands and contracts from the damping cylinder with damping action. In a vehicle shock absorber provided with a connecting bracket connected to a vehicle body or a suspension member, respectively, the piston rod and the connecting bracket provided on the piston rod side are integrally configured. is there.

Therefore, the screw portion for fixing the piston rod and the connecting bracket is not required, and the overall length of the shock absorber is shortened by the amount of the screw portion. Therefore, even if the lever ratio of the suspension is increased, the shock absorber does not interfere with other parts, and the suspension stroke can be lengthened.

In the vehicle shock absorber according to the present invention, the piston rod and the connecting bracket provided on the piston rod side are made of a light material such as a light alloy, and the sliding surface of the piston rod has a surface. It is characterized by being subjected to a curing treatment.

Therefore, the piston rod and the connecting bracket are extremely lightweight, and in combination with the reduction in the overall length of the shock absorber, it is possible to greatly contribute to the weight reduction of the shock absorber. In this case, particularly, the unsprung weight is reduced, so that the road surface followability of the wheel and the riding comfort can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a shock absorber showing an embodiment of the present invention.

FIG. 2 is a left side view of a motorcycle showing an example of a vehicle to which the present invention has been applied.

FIG. 3 is an enlarged view of a shock absorber.

FIG. 4 is a vertical cross-sectional view of a shock absorber showing a conventional technique.

[Explanation of symbols]

 1 Motorcycle as an example of a vehicle to which the present invention is applicable 2 Body frame 5 Pivot shaft 7 Swing arm 12 Suspension device 13 Shock absorber 14, 15 Link member 14 16 which is a suspension member 14 Damping cylinder 17 Piston rod 17a Sliding piston rod Moving surface 23 Spring 24, 25 Connecting bracket

Claims (2)

[Claims] 1. A damping cylinder, and a piston rod that expands and contracts from the damping cylinder with a damping action, and the damping cylinder and the piston rod are provided with coupling brackets that are coupled to a vehicle body or a suspension member, respectively. A shock absorber for a vehicle, wherein the piston rod and the connecting bracket provided on the piston rod side are integrally configured. 2. The piston rod and a connecting bracket provided on the piston rod side are made of a lightweight material such as a light alloy, and the sliding surface of the piston rod is surface-hardened. The shock absorber for a vehicle according to claim 1.