JPH032744Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention relates to the structure of the operating part of a damping force adjustment rod, and is particularly applicable to the upper end of a hydraulic shock absorber where mud and dirt may adhere, such as those used in motorcycles, buggies, etc. This invention relates to an improvement in the structure of the operating section of a damping force adjustment rod.

[Conventional technology]

Hydraulic shock absorbers installed on motorcycles, buggies, etc. often get muddy dirt attached to them depending on the driving conditions. If the hydraulic shock absorber has an adjustment rod and is formed so that the damping force generated when the hydraulic shock absorber expands and contracts can be adjusted from the outside, the dirt and grime mentioned above may be removed from the adjustment rod. It tends to get attached to the operating section. Furthermore, if the mud and dirt adheres to the operating section of the adjustment rod, the smooth operation of the operating section will be hindered, resulting in the inconvenience that the desired damping force adjustment cannot be carried out smoothly.

By the way, as an operating part structure of the above-mentioned damping force adjustment rod, there is a structure as shown in FIG. 2, which has been proposed in the past. That is, the upper end of the operating rod 2 inserted through the shaft core of the piston rod 1 constituting a hydraulic shock absorber (not shown) protrudes from the upper end of the piston rod 1, and the pinion 3 is attached to the protruding end. It is fitted. A rack shaft 4 is meshed with the pinion 3. Furthermore, the rack shaft 4 has one end as an operating end 4a, and the other end as a tip 4b having a fitting groove 5a for a detent mechanism. Further, the rack shaft 4 is held by a suitable guide member 6 so as to allow rotation of the pinion 3, that is, rotation of the operating rod 2, during its horizontal movement.

Therefore, by operating the rack shaft 4 through the operating end 4a of the rack shaft 4 into the guide member 6 or pulling it out from the guide member 6, the operating rod 2 can be operated. It is rotated as desired, and the damping force generated when the hydraulic shock absorber expands and contracts can be adjusted as desired.

[Problem that the invention attempts to solve]

However, in the above-mentioned conventional proposal, since the guide member 6 is formed only to enable horizontal movement of the rack shaft 4, the fitting groove 5a for the detent mechanism is particularly limited. The distal end portion 4b having the above-mentioned distal end portion 4b is exposed to the outside from the end portion of the guide member 6, so that the mud and dirt described above easily adhere to the fitting groove 5a of the distal end portion 4b. When the mud stains are attached to the fitting portion 5a of the tip end 4b of the rack shaft 4, the rack shaft 4
By repeating the horizontal movement operation, the mud is drawn into the guide member 6, that is, into the meshing part of the rack shaft 4 and the pinion 3, which deteriorates the meshing condition between the rack shaft 4 and the pinion 3. or reduce the operability of the control rod 2.
The piston rod 1 may enter the rotating portion at the upper end of the piston rod 1, impeding the rotation of the operating rod 2 and making it impossible to adjust the desired damping force.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a new structure in which mud and dirt do not adhere to the tip of the rack shaft and do not impede the operability of the operating section of the damping force adjustment rod.

[Means for solving problems]

In order to solve the above-mentioned problems, the structure of the present invention is a rack shaft that moves horizontally to the upper end pinion of the adjustment rod, which is formed to allow external adjustment of the damping force generated when the hydraulic shock absorber expands and contracts. A dust cover is disposed on the operation part formed by engaging the rack shaft, and the dust cover has a lip seal part formed to allow the operation end of the rack shaft to protrude outside. In addition, the dust cover is characterized in that it has an extensible part formed so as to be able to cover and isolate the tip of the rack shaft from the outside.

〔Example〕

Hereinafter, the present invention will be explained based on the illustrated embodiments.

As shown in FIG. 1, the operating section of the damping force adjustment rod according to the most preferred embodiment of the present invention is connected to a pinion 3 fitted to the upper end of an adjustment rod 2 inserted through the axial center of the piston rod 1. It is formed by meshing the rack shaft 4. The pinion 3 and other parts of the rack shaft 4 except for the operating end 4a are covered with a dust cover 7.

The pinion 3 is formed to be able to rotate clockwise and counterclockwise in the figure, and the rotation of the pinion 3 causes the lower adjustment rod 2 to rotate. There is. In addition, the rack shaft 4
is held by a guide member 6 so as to be movable in the left-right direction in the figure, and a display section 4 is mounted on the operating end 4a.
c is formed, and a detent mechanism 5 is formed at the tip 4b.
A fitting groove 5a is formed.

The detent mechanism 5 has a spring piece 5b formed so that its tip fits into the fitting groove 5a, and the rear end of the spring piece 5b is fixed at an appropriate position with a screw 5c.

The dust cover 7 has a lip seal portion 7a positioned at one end, that is, the operating end 4a side of the operating rod 4, and the other end, that is, a tip portion 4 in which the fitting groove 5a of the detent mechanism 5 is formed.
On the b side, there is provided an extensible part 7b which covers the tip part 4b so as to isolate it from the outside and which extends to allow the rack shaft 4 to move horizontally.

The lip seal portion 7a is formed such that its outer edge serves as a guide for the display portion 4c at the operating end portion 4a of the rack shaft 4.
It is formed so that the state of protrusion and retraction of the rack shaft 4 into the dust cover 7, that is, the rotating state of the pinion 3 meshing with the rack shaft 4 can be visually recognized from the outside.

Even if the mud and dirt described above may adhere to the operating end 4a of the rack shaft 4, when the operating end 4a is moved into and out of the dust cover 7, the lip seal portion 7a This will prevent it from getting into the interior, ie, the meshing part between the pinion 3 and the rack shaft 4.

It goes without saying that the above-mentioned mud and dirt will not adhere to the fitting groove 5a for the detent mechanism 5 in the tip end 4b of the rack shaft 4.

[Effect of idea]

As described above, according to the present invention, although the operating end of the rack shaft that engages with the pinion is exposed to the outside, the lip seal portion of the dust cover prevents dirt from entering the dust cover, and the day tent mechanism Since the tip part forming the fitting groove for the dust cover is accommodated in the extensible part of the dust cover, mud and dirt from the outside will not adhere to it, and there is no fear that the operability of the rack shaft will be deteriorated.

As a result, there is no fear that the rotatability of the adjustment rod will be impaired, and the damping force can be adjusted as desired.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the structure of an operating section of a damping force adjusting rod according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view showing the structure of an operating section of a conventional adjusting rod. 1...Piston rod, 2...Adjustment rod 3...
... Pinion, 4 ... Rack shaft, 4a ... Operation end, 4b ... Tip, 4c ... Display section, 5 ... Detent mechanism, 5a ... Fitting groove, 6 ... Guide member, 7 ... Dust cover, 7a...lip seal, 7b...extensible part.

Claims (1)

[Claims for Utility Model Registration] (1) The adjustment rod is rotated by meshing with the upper end pinion of an adjustment rod formed to allow external adjustment of the damping force generated when the hydraulic shock absorber expands and contracts. In the structure of the operating part of the damping force adjustment rod, which has a rack shaft that moves horizontally so as to allow movement, a dust cover is disposed on the operating part, and the dust cover covers the operating end of the rack shaft. a lip seal portion formed to allow the lip seal portion to protrude to the outside;
The operating part structure of the damping force adjustment rod is characterized in that the dust cover has an extensible part formed so as to be able to cover and isolate the tip of the rack shaft from the outside. . (2) The operating section structure of the damping force adjusting rod according to claim 1, wherein the operating end of the rack shaft is formed with a display section using the outer edge of the lip seal as a guide. (3) The operating part structure of the damping force adjusting rod according to claim 1, wherein the rack shaft is formed with a fitting groove for the detent mechanism.