JP2581258Y2 - Automotive bumper - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile bumper.

[0002]

2. Description of the Related Art In recent years, a synthetic resin bumper has been used in place of a conventional sheet metal in order to reduce the weight of a vehicle, and is provided so as to cover a synthetic resin backup beam and its front surface. A conventional synthetic resin bumper comprising a bumper face formed and a shock absorbing material made of foamed polypropylene interposed between the backup beam and the bumper face is conventionally known (for example, Japanese Patent Application Laid-Open No. 2-175451). Reference). This synthetic resin bumper is attached to the vehicle body by fastening two right and left portions of the backup beam to the front portions of the left and right bumper stays fixed to the vehicle body with bolts and nuts.

[0003]

In the above-mentioned synthetic resin bumper, when an impact is actually applied, the force acts only on the attachment portion to the vehicle body (the attachment portion to the bumper stay). Nevertheless, the conventional one has a problem that once the shock absorber is crushed, the entire bumper needs to be replaced.

[0004] The present invention has as its main object to address the above conventional problems.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to a bumper body comprising a bumper face or a combination of a bumper face and a shock absorbing material such as foamed polypropylene, which is compressed and elastically deformed by a load at the time of a collision, and a compression deformation of the bumper body. It consists of a backup beam made of synthetic resin for receiving a load, in an automobile bumper which is mounted supported on the vehicle body to the backup beam at bumper stay, the backup beam
Open long holes in the upper and lower surfaces in the longitudinal direction of the vehicle body,
Above the backup beam above the bumper face
Provide a sub-beam to support the
The backup beam and bumper face are located at the bottom of the
A mounting member for supporting the lower part is provided.
Paste, mounting member and above and below the backup beam
The backup beam is attached to a bumper stay together with the sub-beam and the mounting member so that the backup beam can be moved backward by a predetermined stroke by a bolt and a nut penetrating a long hole of the surface. An energy absorbing material such as a synthetic resin honeycomb, for example, having a load at which a compressive fracture is initiated is smaller than a load of the crushing fracture of the bumper body, is interposed between the front surface and the front surface of the bumper body.

[0006]

According to the above, when the bumper body is compressed and elastically deformed at the time of collision and the reaction force acts on the backup beam, the backup beam moves backward with respect to the bumper stay while compressively elastically deforming the energy absorbing material, and the collision energy as a whole of the bumper is changed. The absorption performance is improved. When the bumper body is further compressed, before the bumper body is crushed and broken, the energy absorbing material starts to be broken, and the energy absorbing material is absorbed by the buckling stroke of the breaking of the energy absorbing material, and the energy absorbing material is connected to the fuse. And the restorable collision load of the bumper body becomes higher than before. Also,
Front and rear of the vehicle body provided on the upper and lower surfaces of the backup beam as shown
The backup beam with a sub-beam
By tightening bolts and nuts together with the
By adopting a configuration that attaches to the bumper stay,
Aim to simplify the mounting structure of the
Can be.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional side view of a mounting portion of a bumper to a vehicle body, showing an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a bumper face, 2 denotes a backup beam made of synthetic resin, 3 denotes a shock absorbing material interposed between the bumper face 1 and the backup beam 2, and the shock absorbing material 3 For example, it is made of expanded polypropylene.

The backup beam 2 has a front surface 21 and an upper surface 2
2 and a lower surface 23.
At a location, the bumper stay 5 is mounted and supported on a vehicle body (not shown) (for example, a vehicle body frame).

The mounting holes 22a and 23a provided on the upper surface 22 and the lower surface 23 of the backup beam 2 are elongated holes in the front-rear direction, and are attached to the bumper stay 5 by tightening bolts 8 and nuts 9. Has a structure in which it can be slid rearward with respect to the bumper stay 5 within the range of the elongated hole, and a honeycomb made of synthetic resin (hereinafter referred to as resin) is provided between the front surface 51 of the bumper stay 5 and the front surface 21 of the backup beam 2. The resin honeycomb 10 has a structure in which the back-up beam 2 is prevented from moving backward.

Numeral 4 denotes a sub-beam. The sub-beam 4 is fixed to the vehicle body along the upper part of the backup beam 2 and protrudes from the upper part of the bumper face 1.
a is locked to the sub-beam 4 with a clip or the like (not shown). In the drawing, an example is shown in which the sub-beam 4 is attached and fixed to the bumper stay 5 together with the backup beam 2.

That is, a cylindrical spacer 6 is integrally protruded downward from the mounting hole of the sub-beam 4, and the spacer 6 is inserted into the mounting hole 22a formed by the elongated hole. The sub beam 4 is superimposed on the upper surface 22 of the backup beam 2. Further, a cylindrical spacer 7 is integrally provided in the bolt insertion hole of the mounting member 11 so as to project upward.
Is inserted into the mounting hole 23 a formed of the elongated hole, and the mounting member 11 is overlapped on the lower surface 23 of the backup beam 2. Then, a resin honeycomb 10 is fitted inside the backup beam 2 and the backup beam 2 is fitted to the tip of the bumper stay 5, and bolts 8 are placed in the upper and lower spacers 6 and 7 and the upper and lower holes of the bumper stay 5. Through from below,
The nut 9 is screwed and tightened from below.

Then, the lower edge of the spacer 6 and the spacer 7
The upper edge is fastened to the upper and lower surfaces of the bumper stay 5 so that the sub-beam 4 and the mounting member 11 are rigidly connected to the bumper stay 5, and the backup beam 2 is between the sub-beam 4 and the bumper stay 5 and between the mounting member 11 and the bumper stay 5. The bumper stay 5 is relatively loosely attached to and supported by the bumper stay 5 and the front surface 51 of the bumper stay 5
The resin honeycomb 10 is interposed between the backup beam 2 and the back side of the front surface 21 of the backup beam 2, whereby the backup beam 2 is held at the frontmost position in the movable range in the front-rear direction.

As described above, the sub-beam 4 supports the upper portion of the bumper face 1 and supports the upper edge of the bumper face 1 and the vehicle body thereabove regardless of the deformation of the backup beam 2 during a light collision. Since the parting line is kept constant, it is necessary that the bumper stay 5 fixed to the vehicle body be rigidly connected to the bumper stay 5 irrespective of the backup beam 2 as described above. Mounting member 11
The bumper face support has an area required to suppress the periphery of the lower surface mounting hole 23a of the backup beam 2 and mainly serves as a washer, and has a rear end portion at which a lower portion of the bumper face 1 is locked by a clip 12. Part 11a
, Which also has a function of supporting the lower portion of the bumper face, and is provided with an engaging portion 11b which engages with the rear end of the lower surface of the backup beam 2 and serves as a detent function when tightening the nut.

[0016] As described above, benefit by having a structure for mounting the bumper stay 5 sub-beams 4 by backup beam 2 and tightened, it is possible to reduce the simplicity and mounting steps of the mounting structure of the sub-beam 4, that Ru can lead to.

As described above, the backup beam 2 is mounted on the bumper stay 5 so as to be able to move backward by a predetermined range, and the resin honeycomb 10 is interposed between the back side of the front surface 21 of the backup beam 2 and the front surface 51 of the bumper stay 5. The state of the bumper at the time of collision will be described below with reference to FIGS.

In a normal state, the backup beam 2 is held at the foremost position by the resin honeycomb 10 as shown in FIG.

The rearward load caused by the collision causes bumper face 1
, The shock absorbing material 3 near the load input portion undergoes compression elastic deformation, and the reaction force acts on the backup beam 2. Then, the backup beam 2 moves backward while compressively elastically deforming the resin honeycomb 10 as shown in FIG. 2B.

When the rearward load applied to the backup beam 2 increases due to the compressive elastic deformation of the shock absorbing member 3, the shock absorbing member 3 shown in FIG.
(C), the resin honeycomb 10 is broken, and the backup beam 2 moves to the rearmost position.

In the above description, the characteristics of the compression deformation stroke of the bumper body made of the bumper face 1 and the shock absorbing material 3 and the resin honeycomb 10 with respect to the backward load are set as shown in FIGS. That is, FIG.
As shown in FIG. 7, the change in the compression stroke with respect to the load of the resin honeycomb 10 is smaller than that of the bumper body composed of the bumper face 1 and the shock absorbing material 3, and the load P1 at which the fracture starts is smaller than the load P2 of the crushing of the bumper body. It is set to be.

Accordingly, the change in the stroke with respect to the load of the entire bumper has a characteristic c obtained by combining the above a and b, so that the energy absorption performance at the time of collision is improved and P1
By setting P2, the resin honeycomb 10 plays the role of a fuse, and the resin honeycomb 10 starts to be broken before the bumper body including the bumper face 1 and the shock absorber 3 is crushed and broken. The collision energy is absorbed by the breaking buckling stroke. If the collision is such that only the resin honeycomb 10 is broken, the entire bumper need not be replaced, and only the resin honeycomb 10 needs to be replaced.

If the configuration of the present invention is adopted, 8 km / H
The bumper can be restored even in a collision at a slightly higher vehicle speed.

In the above embodiment, an example in which the present invention is applied to a resin bumper of a type in which a collision load of a bumper body composed of a bumper face and a shock absorbing material such as foamed polypropylene is received by a synthetic resin backup beam. As shown, the present invention comprises only a synthetic resin bumper face in which the bumper body is provided with ribs on the back side as appropriate, and the upper and lower rear ends of the bumper face are locked and held by a synthetic resin backup beam. Thus, the present invention can be applied to a cavity-type resin damper that absorbs the impact at the time of collision by elastic deformation of the bumper face.

The resin honeycomb 10 can be replaced with any energy absorbing material having the characteristics shown in FIG.

[0026]

As described above, according to the present invention, in a synthetic resin bumper including a bumper face, a shock absorbing material, and a backup beam, or in a cavity type synthetic resin bumper including a bumper face and a backup beam,
A backup beam is mounted on the bumper stay so as to be movable rearward by a predetermined stroke, and a load between the back side of the front side of the backup beam and the front side of the bumper stay is such that the load at which compressive fracture starts is made of the bumper face and only the shock absorbing material or the bumper face. By interposing an energy absorbing material, such as a synthetic resin honeycomb, having a smaller load than the crushing failure of the main body, the back-up beam accompanying the elastic compressive deformation of the bumper main body at the time of a collision causes the energy absorbing material to elastically compress and deform rearward. To improve the collision energy absorption performance without increasing the size of the bumper body, and the energy absorbing material begins to break before the bumper body collapses and breaks, and the collision energy is absorbed by the breaking buckling stroke. The energy-absorbing role of the fuse However, if the collision load that can restore the bumper can be increased and the energy absorbing material alone is destroyed, the entire bumper does not need to be replaced and only the energy absorbing material needs to be replaced. The effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a bumper mounting portion, showing an embodiment of the present invention.

FIGS. 2A and 2B are cross-sectional views sequentially showing aspects at the time of collision, and FIG.
Indicates the collision before, (B) indicates the initial stage of the collision, and (C) indicates the final stage of the collision.

FIG. 3 is a diagram illustrating compression stroke characteristics of a bumper body and a resin honeycomb made of a bumper face and an impact absorbing material with respect to a load generated at the time of a collision, and a compression stroke characteristic obtained by combining them;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bumper face 2 Backup beam 3 Shock absorber 5 Bumper stay 8 Bolt 9 Nut 10 Honeycomb made of synthetic resin 22a Mounting hole 22b Mounting hole

Claims (2)

(57) [Scope of request for utility model registration] 1. A bumper body comprising a bumper face or a bumper body comprising a bumper face and an impact absorbing material, and a synthetic resin backup beam which receives a compressive deformation load of the bumper body upon collision. In an automobile bumper mounted and supported on a vehicle body, the backup beam is provided on the upper and lower surfaces of the vehicle bumper.
Open a long hole in the front-back direction and
The upper part of the sub-beam supports the upper part of the bumper face
The backup beam is provided below the backup beam.
Mounting member that supports the bump beam and the lower part of the bumper face
The sub-beam, bumper stay, mounting member and
A bolt that penetrates the slots on the upper and lower surfaces of the backup beam
By the preparative and nut movable so as the sub-beams and collected the backup beam in a predetermined stroke backwards
Attached to the bumper stay with urging member, between the front of the front rear and the bumper stay in the back <br/> up beams, load compressive failure starts small becomes energy absorption than the load of fracture collapse of the bumper body A bumper for an automobile, wherein a load applied to the bumper main body is absorbed by moving a backup beam rearward and compressing and deforming the energy absorbing material with a material interposed therebetween. 2. The energy absorbing material according to claim 1,
An automobile bumper, which is a honeycomb made of a synthetic resin.