JPS6318281Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a shock absorber for a vehicle bumper.

Conventionally, a shock absorber for a vehicle bumper has been proposed that is made of resin and is formed into a honeycomb shape by a plurality of intersecting partition walls that are substantially parallel to the impact direction, and is placed inside the vehicle bumper (for example, Utility Model No. 50-134595).

By the way, the above-mentioned shock absorber absorbs the shock that acts on the vehicle bumper due to the buckling deformation of the bulkhead.However, when a large shock is applied in a low temperature state, the conventional shock absorber absorbs stress on the end face of the bulkhead, especially when a large shock is applied at low temperature. Cracks are likely to occur at the intersections of bulkheads where
There is a problem in that shock absorption is not sufficient.

This invention was made to eliminate the above-mentioned problems, and is a honeycomb-shaped resin shock absorber that is placed between a bumper face with a U-shaped cross section and a reinforcement, and has a partition wall that is approximately parallel to the impact direction. By forming a thick wall portion on an end surface of the partition wall that is close to the vertical surface of the bumper face and an end surface that is near the reinforcement, which is thicker than a middle portion of the partition wall that connects both end surfaces. ,
It is an object of the present invention to provide a shock absorber for a vehicle bumper that can prevent cracks from occurring from the end face of a partition wall.

This invention will be explained in detail below with reference to illustrated embodiments.

In FIGS. 1 and 2, 1 is a resin bumper face having a U-shaped cross section. A metal reinforcement 2 having a rectangular cross section is fitted into the bumper face 1, and the bumper face 1 is attached to the upper surface 2a and lower surface 2b of this reinforcement 2.
The upper part 1a and the lower part 1b are fixed with bolts 3 and 4, respectively, as shown in FIG. In the space between the front surface 2c of the reinforcement 2 and the bumper face 1, a honeycomb-shaped shock absorber 5 made of resin such as polyethylene is arranged, and the bottom 5a of the shock absorber 5 is connected with bolts.・Natsuto 6,
6 is fixed to the front surface 2c of the reinforcement 2.

The above-mentioned shock absorber 5 has a plurality of partition walls 5b, 5b, .
As shown in the figure, they cross each other, forming a honeycomb shape. As shown in FIGS. 2 and 3, the partition walls 5b, 5b, ... are tapered from the bottom part 5a toward the tip due to the mold cutting slope in resin molding. The end face of the bumper face 1 close to the vertical face 1c is provided with thick parts 8, 8, . . . which are thicker than the intermediate portions of the partition walls 5b, 5b, . Moreover, the partition walls 5b, 5
A thick portion 8', which is thicker than the middle portion of the partition wall 5, is formed on the side continuous to the bottom portion 5a of b.

The thick portions 8, 8, . . . are formed, for example, as shown in FIGS. 4 and 5. That is, as shown in FIG. 4, the heating plate 11 is brought close to the end surface of the tip of the partition walls 5b, 5b... of the molded shock absorber 5 taken out from the mold (not shown), and the partition walls 5b, 5b are ... is melted at, for example, 500°C to 800°C, and then solidified, as shown in FIG.
Form 8...

The thick parts 8, 8...; 8', 8',... are the first and third thick parts.
As shown in the figure, they are connected in series, and the intersection 1
Thick wall portions 13; 13' are also formed at 2 and 12'.

Although not shown, the reinforcement 2 is attached to the vehicle body via an attachment member.

The impact absorbing body 5 of the vehicle bumper having the above structure is attached to the bumper face 1 having a U-shaped cross section as indicated by the arrow A in FIG.
When the vertical surface portion 1c of the bumper face 1 is deformed in the direction of arrow A due to the impact acting in the direction, the partition wall 5 is pressed by the vertical surface portion 1c of the bumper face 1.
b, 5b... undergo buckling deformation and absorb the impact.

At this time, since the thick portions 8, 13, . . . ; 8', 13', . 5 can be prevented from cracking. In particular, since the thick portions 13; 13' exist at the intersections of the partition walls 5b, 5b, . . . , stress concentration does not occur and cracks do not occur at the intersections 12; 12'. Therefore, when receiving an impact, the partition walls 5b, 5b, . . . can be buckled and deformed, and the impact absorption ability is improved.

Further, when the vertical surface 1c of the bumper face 1 and the thick parts 8, 13 of the shock absorber 5 come into contact with each other due to an impact, the contact area of the thick parts 8, 13 with the bumper face 1 is Since it is large, large shearing stress does not act on the bumper face 1, and therefore, the bumper face 1 is less likely to crack.

The shock absorber 5 of the above embodiment is provided with a bottom portion 5a, but the modified example shown in FIG. 6 is not provided with a bottom portion. Also in the modification shown in FIG. 6, in addition to the thick part 8', the thick part 5 is formed on the end face of the partition wall 5b that is thinner due to the drafting slope, that is, on the end face of the side that is more likely to break. ing.

As is clear from the above explanation, the resin-made bumper face is formed into a honeycomb shape by a plurality of intersecting partition walls that are substantially parallel to the impact direction, and is placed between the bumper face and the reinforcement, which have a U-shaped cross section. A thick wall portion that is thicker than an intermediate portion of the partition wall that connects both end surfaces is formed on an end surface of the shock absorber partition wall that is close to the vertical surface of the bumper face and an end surface that is near the reinforcement. Therefore, with a minimum increase in weight, stress is dispersed by the thick portions on both end faces, preventing cracks from occurring from the end faces, and cracking of the shock absorber can be completely prevented.

[Brief explanation of the drawing]

Figures 1, 2, 3, 4, and 5 show an embodiment of this invention, with Figure 1 being an exploded perspective view and Figure 2 being a sectional view.
FIG. 3 is a perspective view of a main part, FIGS. 4 and 5 are diagrams for explaining a method of forming a thick part, and FIG. 6 is a sectional view of a main part of a modified example. 1... Bumper face, 2... Reinforcement, 5... Shock absorber, 5b... Bulkhead,
8, 13; 8'13'...Thick walled part.

Claims (1)

[Claims for Utility Model Registration] A resin shock that is formed into a honeycomb shape by a plurality of intersecting partition walls that are substantially parallel to the direction of the shock, and is arranged between a bumper face with a U-shaped cross section and reinforcement. In the absorbent body, an intermediate portion of the partition wall that connects an end surface of each of the plurality of partition walls that is close to the longitudinal surface of the bumper face, and both end surfaces of the partition wall that is close to the reinforcement on the opposite side of the end surface. A shock absorber for a vehicle bumper, characterized by forming a thick walled part that is thicker than that of a vehicle bumper.