JPH0536657B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a bumper bounce that is used in a suspension device of an automobile or the like and is used for abutting a damper main body.

[Background Art] In an automobile suspension device, a damper rod protruding from a damper body expands and contracts with the damper body, thereby damping vibrations by fluid resistance within the damper body.

This damper rod has a bumper bound attached near its tip, which comes into contact with the damper body during large vibrations.

This bumper bound is attached by being inserted into the tip of the damper rod, but in order to prevent the bumper bound from falling out of the damper rod, the insertion hole for the damper rod formed in the bumper bound is stepped. Therefore, there is a gap between the middle part of the insertion hole and the outer periphery of the damper rod.

Therefore, if a large load is applied in the axial direction of the bumper bound, a component force will be applied in the radial direction during compressive deformation, making buckling likely to occur.

[Object of the Invention] Taking the above facts into consideration, the present invention aims to obtain a bumper bounce that does not easily cause buckling even when a large compressive force is applied.

[Summary of the Invention] The present invention has a through hole for inserting a damper rod, which has a small diameter portion at the upper end and a large diameter portion below the through hole, and the small diameter portion and the large diameter portion are connected to a flange portion provided at the upper portion of the damper rod. It is a cylindrical bumper bound that is attached to the damper rod so that the boundary part with the damper rod comes into contact with the damper body, and extends along the axial direction and is divided into a plurality of pieces in the circumferential direction. The damper rod is characterized in that a protrusion whose inner diameter is larger than the outer diameter of the damper rod is formed on the large-diameter inner periphery of the through-hole and in the axially central area of the large-diameter portion.

The pumper bound having the above structure is achieved by forming a protrusion on the inner periphery of the large diameter part of the through hole for inserting the damper rod and in the axially central area of the large diameter part.
This prevents buckling by reducing the displacement that occurs in the radial direction when axial compressive force is applied.

Moreover, since this protrusion extends in the axial direction and is divided into multiple pieces in the circumferential direction, the mold forming the through hole can be easily removed when molding the bumper bound. The flange part can be inserted smoothly.

In addition, in the large diameter section, the inner diameter of the part where the protrusion is formed is larger than the outer diameter of the damper rod, so the protrusion does not constantly slide on the damper rod, which prevents the normal movement of the damper rod. Moreover, wear of the protrusions is also suppressed.

[Embodiment of the Invention] FIG. 1 shows the vicinity of the upper part of a suspension device to which a bumper bound 10 according to the present embodiment is applied. In this suspension device, a damper rod 14 is inserted into a cylindrical damper body 12 whose axis is vertical, and a piston (not shown) is attached to the lower end of the damper rod 14. A through hole is bored in this piston, and when the piston moves, the liquid sealed in the bumper body 12 flows through the through hole, and vibrations are damped by the viscous resistance. ing. Vibration is transmitted to the lower end of the damper body 12 from the wheels of the automobile.

A small diameter bolt 16 coaxially protrudes from the upper end of the damper rod 14.
Washers 18 and spacers 20 are used as flange parts.
and an upper receiving plate 22 are inserted. Washiya 18
The outer diameter of the damper rod 14 is larger than that of the damper rod 14. In addition, these washers 18,
The spacer 20 and the bolt 16 may be formed integrally, and this integral body may be fixed to the upper end of the damper rod 14 by a suitable fitting structure, welding, or the like.

A nut 24 is tightened onto a bolt 16 from above the upper receiving plate 22 to fix the upper receiving plate 22 to the damper rod 14. Note that this upper receiving plate 22 is partially connected to the vehicle body so that it can support the load from the wheels. Further, this upper receiving plate 22 corresponds to a lower receiving plate 26 fixed to the outer periphery of the damper main body 12.
A compression coil spring 28 is interposed between the spring 6 and the spring 6.

As a result, the damper rod 14 is biased in the direction of being pulled out from the damper body 12.

The bumper bound 10 has a cylindrical shape as shown in FIGS. 2 and 3, and is made of synthetic resin such as foamed polyurethane.

The insertion hole for the damper rod passing through the axis of the bumper bounce 10 has a small diameter section 30 at the upper end, and a large diameter section 32 below the small diameter section 30.
is formed. The boundary between the small diameter portion 30 and the large diameter portion 32 is a stepped portion 33.
By contacting the periphery of the washer 18 with the bumper bound 10, the bumper bound 10 is prevented from falling off.

As shown in detail in FIGS. 2 and 3, a plurality of protrusions 34 are formed in the large diameter portion 32 in a direction that reduces the inner diameter of the hole. The tips of these protrusions 34 are the first
As shown in the figure, it is arranged closer to the axis of the damper rod 14 than the outer diameter of the washer 18.

Furthermore, these protrusions 34 are ridges extending in the axial direction, and the upper and lower ends thereof are provided with bumper bounds 10.
It has a tapered shape in which the inner diameter gradually increases toward the upper and lower ends. Also, these protrusions 34
The minimum inner diameter connecting the tip between the damper rod 1
It is preferable that the difference from the outer diameter of No. 4 is 3 mm or less.

In addition, the outer circumference of the bumper bound 10 is tapered to a smaller diameter toward the lower end in the installed state, and has a plurality of notches 3 for adjusting the compressive load.
6 is formed in a ring shape.

Next, the operation of this embodiment will be explained.

In order to attach the bumper bound 10 to the damper rod 14, washers 18 and bolts 16 are required.
is attached to the damper rod 14 in advance, and the large diameter portion 32 of the bumper bound 10 is fitted onto the damper rod 14 from above, that is, from the direction of the bolt 16. As a result, the projection 34 temporarily expands its inner diameter and climbs over the washer 18, and the stepped portion 33 between the small diameter portion 30 and the large diameter portion 32 comes into contact with the washer 18 as shown in FIG. insertion stops.

After that, attach the upper receiving plate 22 onto the spacer 20 and tighten the nut 24 to complete the assembly. Since the small diameter portion 30 of the bumper bound 10 is locked to the washer 18, the damper rod 14
It will not fall off.

The washer 18 and spacer 20 may be attached to the bumper bound 10 in advance, and this subassembly part may be attached to the damper rod 14.

In the suspension device assembled in this manner, vibrations generated as the vehicle travels are attenuated and absorbed by the relative movement in the axial direction between the damper 12 and the damper rod 14.

If this vibration is large, the damper body 12
moves upward in FIG. 1 more than necessary and comes into contact with the lower end of the bumper bound 10. Even when this contact load is large, the distance between the bumper bound 10 and the outer periphery of the damper rod 14 is small, so the amount of eccentric displacement in either radial direction is small, and buckling almost never occurs. There's nothing to do. This allows the bumper bound 10 to reliably absorb the load when the damper body 12 overstrokes.

Also, even when the bumper bounce 10 repeats compressive deformation and recovery, the damper rod 14
Since the contact area with the outer diameter of the
Frictional wear and noise generation are reduced.

In the above embodiment, as shown in FIG.
Although six protrusions 34 are formed around the axis, in the second embodiment shown in FIG.
Individually formed.

Furthermore, in the third embodiment shown in FIG. 5, 12 holes are formed around the axis.

However, in each of these embodiments, the protrusion 34
Similarly, since there is only a small distance between the damper rod 14 and the outer periphery of the damper rod 14, the same effect as in the previous embodiment can be obtained.

[Effects of the Invention] As explained above, in the bumper bound according to the present invention, the protrusion is formed on the inner periphery of the large diameter part of the through hole for inserting the damper rod and in the axial center area of the large diameter part, so that axial compression is reduced. Even when the force is large, it has the excellent effect of limiting buckling in the radial direction and absorbing the load appropriately.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the bumper bound according to the first embodiment of the present invention in an installed state, FIG. 2 is a cross-sectional view taken along the line of FIG. 1, and FIG. 3 is a cross-sectional perspective view of the bumper bound of the first embodiment. , 4 and 5 are sectional views corresponding to FIG. 2 showing second and third embodiments of the present invention, respectively. 10... bumper bound, 12... damper body, 14... damper rod, 30... small diameter section, 32... large diameter section.

Claims (1)

[Scope of Claims] 1. A through hole for inserting a damper rod, which has a small diameter part at the upper end and a large diameter part below it, and the small diameter part and the large diameter part are connected to the flange provided at the upper part of the damper rod. It is a cylindrical bumper bound that is attached to the damper rod so that the boundary part of the damper body comes into contact with the damper body. A bumper bounce characterized in that a protrusion whose inner diameter is larger than the outer diameter of the damper rod is formed on the inner periphery of the large diameter portion of the through hole and in the axially central area of the large diameter portion.