JP2877167B2 - Bump stopper - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bump stopper for buffering an operation of a strud rod or the like in a vehicle suspension mechanism.

[Prior Art] FIGS. 3 and 4 each show an example of a bump stopper of a mount structural member used for the purpose of restraining and damping the movement of a movable rod such as a straddle rod. That is, a main body 1 of a bump stopper formed of an elastic material such as rubber is fixed to a dust cover (not shown) at one upper end in the drawing, and penetrates along an axial direction toward the fixed end 2. A hole 3 is provided. Following the fixed end 2, a bellows-like elastic portion 4 capable of elastic expansion and contraction is provided, and the distal end of the elastic portion 4 is a free end 5.

As shown in the figure, the diameter is gradually reduced in the axial length direction from the fixed end 2 to the free end 5 at the tip, and the tapered shape. A rod is movably inserted into the through-hole 3, and when the rod repeatedly moves forward and backward in the axial direction, the flange flange of the cylinder located at the end of the rod abuts on the free end 5 from below in the figure, and that of the rod. It has a function of stopping the movement while buffering the movement.

In the type shown in FIG. 3, a plurality of ridges 4a and 4b provided on a bellows-shaped elastic portion 4 are straight portions parallel to the axis, and the type shown in FIG. Mountain 4a, 4b ~
Is a tapered shape inclined at an angle α with respect to the axis.

[Problems to be Solved by the Invention] By the way, in the bump stopper having such a shape, if the axial length from the fixed end 2 to the free end 5 at the tip becomes long, the following problem occurs. As shown in FIG. 3, when the plurality of peaks 4a to 4 are straight, an arrow F
When a load is applied, the entire body 1 is compressed as shown by the imaginary line and elastically deforms. Similarly, the fourth
In the case of the figure, when a load is applied, the entire main body 1 undergoes elastic deformation as indicated by a virtual line.

State of the elastic deformation, when the type of FIG. 3, no is so large脹viewed diameter D ₂ which is deformed radially, but unchanged almost in comparison with the outside diameter D of the original body 1, deformation good It is hard to say the shape. In contrast, the type of FIG. 4, the radial脹Mino shape is good, and very large change is脹saw diameter D ₃ compared to the outer periphery diameter D of the original body 1, over time There is a possibility that the use may have an adverse effect on durability.

An object of the present invention is to solve the problems of both types shown in FIGS. 3 and 4, and to provide a bump stopper having both advantages.

[Means for Solving the Problems] A bump stopper according to the present invention is a bellows-like expansion and contraction in which peaks and valleys are alternately connected between a fixed end and a free end on the axis of a main body. A portion is provided, and a peak portion is formed by a straight portion parallel to the axis of the main body and a tapered portion having an inclination angle.

[Operation] Since the crests of the expansion and contraction portions provided on the main body are formed by straight portions parallel to the axis of the main body and tapered portions having a predetermined inclination angle, the expansion and contraction portions are caused by a load applied in the axial direction. When compressed, there is little radial expansion of the entire body, and the expanded shape is uniform and orderly. As a result, durability during use over time is enhanced.

Hereinafter, an embodiment of a bump stopper according to the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, in a bump stopper 10 of the embodiment, a main body 11 has a fixed end 12 and a free end 13 on one side and the other side in the axial direction, and can be elastically expanded and contracted between both ends. A flexible bellows-like elastic portion 14 is provided. Further, a through hole 16 through which the rod is inserted is provided on the central axis. That is, due to the linear movement of the rod, the flange flange provided at the upper end of the rod abuts on the free end 13 of the distal end of the elastic part 14 from below, so that the entire main body 11 is compressed in the axial direction. In other words, the body
The structure is such that the rod 11 is prevented from moving further upward by abutting the free end 13 on the free end 13 while stopping the rod.

Here, as is apparent from FIG. 2, the expansion and contraction portion 14 is formed by a plurality of peaks and valleys alternately formed, and the plurality of peaks 15 are each formed of a straight portion 15a and a tapered portion 15b parallel to the axis. I have. That is, the tapered portion 15b having the length b is connected to the straight portion 15a having the length a parallel to the axis and inclined at the angle β.

With the above-described configuration, the following effects occur in the bump stopper 10 of the embodiment.

External force due to vibration and shock during vehicle operation acts on the suspension mechanism mounted around the undercarriage of the wheel, and the rod moves linearly in the axial direction in accordance with the strength of the external force. During this forward / backward movement, the flange flange at the rod end is
Abut. The elastic part 14 contracts due to the compressive force of the contact force,
When the elastic contraction to a certain extent stops the movement of the rod,
Buffer operation.

During such operation, as shown by the imaginary line in FIG. The elastic deformation at this time is such that the ridge 15 in the expansion and contraction portion 14 is composed of the straight portion 15a and the tapered portion 15b, so that there is little radial expansion due to the action of these two portions, and the outer periphery of the original main body 11 It requires only脹saw diameter D ₁ that does not significantly change the diameter D. Also. Since the shape of the swelling is uniform and orderly, it is possible to maintain good durability over time.

That is, both of the advantages of the bump stopper having the shape shown in FIG. 3 and FIG. 4 shown as a conventional example have two advantages, that is, the expansion during compression is small and the expansion is good. it can.

[Effects of the Invention] As described above, the bump stopper according to the present invention is characterized in that, when a load is applied to the main body and a compressive force is applied in the axial direction, the crest of the elastic portion is straight and parallel to the axis. Because it is formed from a tapered part with a suitable angle of inclination, it has less deformation in the radial direction and expands in a uniform and orderly shape, so that it has the advantage of maintaining durability over time. There is.

[Brief description of the drawings]

1 and 2 show a sectional view and a partially enlarged sectional view of an embodiment of a bump stopper according to the present invention. 3 and 4 are cross-sectional views of two types of conventional bump stoppers. [Explanation of symbols] 10… Bump stopper 11… Main body 14… Expansion part 15… Crest part 15a …… Crest part straight part 15b …… Crest part of peak part

Claims (1)

(57) [Claims] 1. A bellows-shaped elastic part which is elastically expandable and contractable by alternately forming peaks and valleys between a fixed end and a free end on the axis of the main body, wherein the peak is the axis of the main body. A bump portion formed by a straight portion parallel to the first portion and a tapered portion having an inclination angle.