JPH082351A - Car bumper structure - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] The impact absorbing part is integrally formed to reduce the number of parts and cost, and to create a rib structure that does not easily transmit a shocking local load. The mold forming means is used at the time of molding the bumper to enable molding on the shape surface formed on the core mold on the upper mold side, thereby facilitating adjustment of proof stress in the shock absorbing portion. [Composition] A bumper face 3 is provided so as to cover a bumper reinforcement 2 formed of a resin containing glass fiber and extending in the vehicle width direction, and the bumper face 3 is provided between the bumper reinforcement 2 and the bumper face 3. Has a shock absorbing portion 6 formed integrally with the bumper face 3,
The shock absorbing portion 6 includes a partition wall 7, a thin rib 8 integrally formed on the partition wall 7 and facing the bumper reinforcement 2, and a thick rib 9 integrally formed on the partition wall 7 and extending to the bumper face 3 side. The thick ribs 9 and the thin ribs 8 are arranged in a row in the vehicle front-rear direction across the partition wall 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle bumper structure such as a front bumper provided at a front end portion of a vehicle in a vehicle width direction and a rear bumper provided at a rear end portion of the vehicle in a vehicle width direction.

[0002]

2. Description of the Related Art Conventionally, as a bumper structure of an automobile, for example, a front bumper structure, there is a structure shown in FIG. That is, a bumper reinforcement 9 made of a resin containing glass fiber extended in the vehicle width direction at the front end portion of the automobile.
1 and a bumper face 92 made of a thermoplastic such as polypropylene for covering the bumper reinforcement 91 described above are provided, and a metallic reinforcing retainer 94 attached to the bumper reinforcement 91 with a clip 93 is used. This is a front bumper structure for an automobile, in which the bumper face 92 described above is fixed and an energy absorber 95 made of foamed resin is provided between the bumper face 92 and the above-mentioned bumper reinforcement 91. In the figure, 96 is an extension.

According to this conventional front bumper structure for an automobile, an excellent load curve as shown in FIG. 13 can be obtained. In FIG. 13, the horizontal axis shows an example of the amount of deformation at the time of a slight collision of the vehicle at a certain speed, and the vertical axis shows an example of the generated load. A range d indicates a load absorbing area by the energy absorber 95, and a range e indicates a load absorbing area by the bumper reinforcement 91. The load curve in FIG. 13 is a smooth continuous line without exceeding the reinforcement proof line. It becomes a nice curve.

However, in the vehicle front bumper structure shown in FIG. 12, the material and manufacturing method of each element 92, 94, 95 are different, and the number of parts is large, so that the cost is reduced. Was difficult.

In order to solve such a problem, for example, as shown in FIGS. 14 and 15, a configuration in which the above-mentioned energy absorber 95 made of foamed resin is substituted is conceivable. That is, with respect to the bumper face 92 described above, a vertical wall 97 and a thick rib 98 extending from the vertical wall 97 to the bumper face 92 side.
By integrally forming the shock absorbing portion 99 including the, the cost of the bumper structure can be reduced.

However, in the case of the construction shown in FIGS. 14 and 15, the load curve of the bumper reinforcement 91 made of the resin containing glass fiber is brittle against the impact local load. However, there was a problem that it deteriorated significantly. That is, in FIG. 16, a range f indicates a load absorbing area by the shock absorbing portion 99, and a g indicates a fracture area of the bumper reinforcement 91.
In the structure mainly consisting of the thick ribs 98 of FIG.
There is a problem that the bumper reinforcement 91 is broken at the time of a slight collision at a certain speed of the vehicle beyond the proof line of No. 1 and the load curve falls.

On the other hand, as another example of the conventional bumper structure for an automobile, there is a structure described in Japanese Utility Model Laid-Open No. 57-37051. That is, as shown in FIG. 17, a resin bumper 101 for covering the metal back plate 100 is provided, and a plurality of thin ribs 103 are provided on the front side of the partition wall 102 extending in the vertical direction, and a plurality of thick ribs 104 are provided on the rear side. The bumper structure of the automobile is formed integrally with each other, and the ribs 103 and 104 are configured to absorb the impact at the time of a collision.

However, in this conventional bumper structure for an automobile, since the bumper 101 is formed by resin extrusion molding, the shock absorbing portion, that is, both ribs 10 is formed.
There is a problem that it is difficult to adjust the yield strength of 3,104 (so-called yield strength tuning).

[0009]

SUMMARY OF THE INVENTION According to the present invention, the impact absorbing portion is integrally formed with the bumper face, so that the number of parts of the bumper structure can be reduced and the cost can be reduced. The bumper made of resin containing glass fiber, which is fragile with respect to the load, has a rib structure that makes it difficult for an impacting local load to be transmitted to the reinforcement. By facing the reinforcement,
At the time of molding the bumper, by using a mold molding means consisting of an upper mold and a lower mold, it is possible to mold the above-mentioned thin rib on the shape surface to be molded into the core mold on the upper mold side, and adjust the proof stress of the shock absorbing part. An object is to provide an automobile bumper structure that can be easily performed.

[0010]

SUMMARY OF THE INVENTION The present invention is a vehicle bumper structure provided in the vehicle width direction at a front end portion or a rear end portion of an automobile, which is formed of glass fiber-containing resin and extends in the vehicle width direction. A bumper reinforcement is disposed at a front end or a rear end of the automobile, a bumper face is provided so as to cover the bumper reinforcement, and the bumper reinforcement is provided between the bumper reinforcement and the bumper face. A shock absorbing portion integrally formed with the bumper face is formed. The shock absorbing portion is a partition wall, a thin rib integrally formed with the partition wall and facing the bumper reinforcement, and a bumper face side integrally formed with the partition wall. A bumper for an automobile, comprising: a thick rib extending; and the thick rib and the thin rib arranged in a row in the vehicle front-rear direction with the partition wall therebetween. Characterized in that it is a concrete.

[0011]

According to the present invention, since the shock absorbing portion including the partition wall, the thin rib and the thick rib is integrally formed with the bumper face described above, the bumper face and the shock absorbing portion are formed. The material and the manufacturing method can be made common, and as a result, the number of parts of the bumper structure can be reduced and the cost can be reduced.

Although the above-mentioned bumper reinforcement made of glass fiber-containing resin is vulnerable to a shocking local load, the above-mentioned shock absorbing portion integrally forms a thick rib on the bumper face side of the partition wall. Thin ribs are integrally formed on the bumper reinforcement side of the vehicle, and the thick ribs and the thin ribs are arranged in a row in the vehicle front-rear direction with the partition wall interposed therebetween to provide an impact against the bumper reinforcement. Since the rib structure is such that it is difficult for a local load to be transmitted, a good load curve can be obtained.

Moreover, since the above-mentioned thin rib is opposed to the bumper reinforcement, the following effects are obtained.
That is, when forming a bumper in which the above-described shock absorbing portion is integrally formed on the bumper face, a die forming means including an upper die and a lower die is used to adjust the number and thickness of the thin ribs to the upper die side. It is possible to enable molding in the shape surface formed in the core mold, and as a result, it is possible to easily adjust the proof stress of the shock absorbing portion (so-called proof tuning).

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. The drawings show the front bumper structure of an automobile. In FIGS. 1 and 2, a bumper reinforcement 2 is attached to the front ends of vehicle body side frames 1 and 1 (front side frames) extending in the front-rear direction of the vehicle body. The bumper reinforcement 2 is a member formed of a resin containing glass fiber and extending in the vehicle width direction.

A bumper face 3 made of resin (for example, polypropylene) is provided so as to cover the bumper force 2 described above. The bumper face 3 has a number plate mounting portion 4 at the center of the front end thereof and a traveling air intake 5 for cooling the radiator, which extends in the vehicle width direction. Further, the shock absorbing portions 6 ... That extend in the vertical direction are integrally formed at a predetermined portion of the bumper face 3 at a total of eight locations.

Here, the above-mentioned eight shock absorbing parts 6 in total.
Of the two shock absorbing parts 6,6 located in the center of the ..., that is, the two shock absorbing parts 6,6 corresponding to the number plate mounting part 4 function as load input parts, and the vehicle body side frames 1,1 The three left and right impact absorbing parts 6 ... at the corresponding positions apply the input load to the vehicle body side frames 1, 1 described above.
Due to the relationship received at, it acts as a damping part corresponding to the part where this load is transmitted.

Specific structures of the bumper reinforcement 2, the bumper face 3, and the shock absorbing portion 6 are as shown in FIGS. 3 to 7. That is, FIG. 3 is a sectional view taken along the line AA of FIG. 1, FIG. 4 is a sectional view taken along the line BB of FIG. 1, FIG. 5 is a sectional view taken along the line CC of FIG. 1, and FIG. 7 is EE of FIG.
The bumper reinforcement 2 described above is formed by a resin containing glass fiber so that its longitudinal section has an inverted U-shape, and a recess 2 is formed at a predetermined position on the front end side.
a is formed.

The shock absorbing portion 6 formed integrally with the bumper face 3 is provided with a partition wall 7 as shown in an enlarged view in FIG.
A plurality of thin-walled ribs 8 formed integrally with the partition wall 7 to face the bumper reinforcement 2 described above, and a rear end portion of which comes into contact with the front surface of the bumper reinforcement 2 including the recess 2a, and the partition wall 7 described above. A thick rib 9 integrally formed on the bumper face 3 and extending toward the bumper face 3 side, that is, the front side, and a brace 10 integrally formed at a required position between the thick rib 9 and the front surface of the partition wall 7 (FIG. 6, FIG. 6). 7)), the thick ribs 9 on the front side and the thin ribs 8 on the rear side are arranged in a row in the vehicle front-rear direction with the partition wall 7 therebetween. In this embodiment, the number of ribs of the thick ribs 9 is set to "1", the number of ribs of the thin ribs 8 is set to "4" to "5", and a bumper for receiving a load through the thin ribs 8 is used. Widen the pressure receiving area on the reinforcement 2 side,
It is configured to reduce the pressure applied to the bumper reinforcement 2.

Further, as shown in FIGS. 3 and 4, a bumper face 3 and a partition wall 7 of the shock absorbing portion 6 are provided at required portions with a connecting portion 11 for connecting them in the longitudinal direction of the vehicle.
The bumper reinforcement 2 and the partition wall 7 described above are attached to each other by a plurality of clips 12. A gap 13 is formed between the tapered surface 9a on the front end side of the thick rib 9 in the impact absorbing portion 6 and the back surface of the bumper face 3 for the purpose of preventing sink marks during molding. In the figure, 14 is an extension and 15 is a front grill.

As described above, since the impact absorbing portion 6 including the partition wall 7, the thin rib 8 and the thick rib 9 is integrally formed with the resin bumper face 3 described above, the bumper face 3 and the impact absorbing portion are formed. 6 and the manufacturing method can be made common, and as a result, the number of parts of the bumper structure can be reduced and the cost can be reduced.

The bumper reinforcement 2 made of a resin containing glass fiber is fragile against an impact local load, but the impact absorbing portion 6 has a thick rib 9 on the bumper face 3 side of the partition wall 7. Integrally formed, a plurality of thin ribs 8 are integrally formed on the bumper reinforcement 2 side of the partition wall 7,
A rib structure in which the thick ribs 9 and the thin ribs 8 are arranged in a row in the vehicle front-rear direction with the partition wall 7 interposed therebetween so that a shocking local load is hardly transmitted to the bumper reinforcement 2 described above. Therefore, there is an effect that a good load curve as shown in FIG. 8 can be obtained.

The characteristic diagram shown in FIG. 8 is a characteristic diagram in which the horizontal axis represents the amount of deformation at the time of a slight collision of the vehicle, and the vertical axis represents the generated load to obtain a load curve. The range, the range b shows the load absorbing region by the thick rib 9, and the range c shows the load absorbing region by the bumper reinforcement 2, respectively. By adjusting the thickness of each of the above elements 8, 9, 2, It was possible to obtain a continuous and smooth load curve without exceeding the reinforcement capacity line. It should be noted that for loads above the load curve shown in FIG. 8, the impact load is absorbed by the crushable zone set at the tip of the vehicle body side frame 1 deforming in a bellows shape.

Moreover, since the above-mentioned thin rib 8 is opposed to the bumper reinforcement 2, the following effects can be obtained. That is, the bumper face 3 has the above-described impact absorbing portion 6
When molding a bumper integrally molded with a mold, a mold forming means including an upper mold and a lower mold is used, the above-mentioned bumper face 3 is formed by the cavity of the lower mold, and the partition wall in the shock absorbing portion 6 is formed by the cavity of the upper mold. 7 side is molded respectively, and the above-mentioned thick ribs 9 are molded by a slide mold, and the number and thickness of the above-mentioned thin ribs 8 can be molded on the shape surface formed on the core mold on the upper mold side. Therefore, it is possible to easily adjust the yield strength of the shock absorbing portion 6, particularly the thin ribs 8 (so-called yield strength tuning).

This point will be described in more detail with reference to FIGS. 9 to 11. FIG. 9 shows a state during molding in a drawing of a die corresponding to a cross section taken along line XX of FIG. 11 and FIG. 11 show the releasing state after the resin is cured. As shown in FIG. 10, the core die 20 is removed in the direction of arrow h (the die removing direction of the core die) at the same time as the state shown in FIG. The slide die 21 fixed to the tip of the core die 20 and the slide die 21.
10, the slide die 21 moves in the direction of arrow j in FIG. 10, and the amount of this movement becomes greater than the length of the partition wall 7, and as shown in FIG. 7 and the slide die 21 are no longer overlapped with each other, the projecting operation of the projecting pin 22 is stopped at the same time, and the core die 20 and the slide die 21 move in the same direction in the core die removing direction indicated by the arrow k in FIG. Then, the rib shape of the product is formed.

In order to easily control the rib thickness of the above-mentioned thin rib 8 for the purpose of not locally inputting a conductive load to the bumper reinforcement 2 made of a resin containing glass fiber, it is necessary to generate the rib thickness at the time of welding during mold modification. The shape surface 24 for forming the thin ribs 8 is formed on the core mold 21 that disperses and absorbs the heat of welding so that the sliding member 23 is not distorted by minimizing the thermal contraction of the mold material. . The formation of such a mold facilitates tuning of the yield strength of the thin rib 8. In addition,
In FIGS. 9 to 11, reference numeral 25 denotes a lower mold.

In the correspondence between the structure of the present invention and the above-mentioned embodiment, the automobile bumper structure of the present invention corresponds to the automobile front bumper structure of the embodiment, but the present invention is only the structure of the above-mentioned embodiment. However, it is needless to say that the above configuration may be applied to a rear bumper structure of an automobile, for example.

[Brief description of drawings]

FIG. 1 is a schematic front view showing a bumper structure for an automobile of the present invention.

FIG. 2 is a schematic plan view showing a bumper structure for an automobile of the present invention.

FIG. 3 is a sectional view of a main part taken along the line AA of FIG.

FIG. 4 is a cross-sectional view of main parts taken along the line BB of FIG.

5 is a cross-sectional view of a main part taken along the line CC of FIG.

FIG. 6 is a cross-sectional view of main parts taken along the line DD of FIG.

7 is an enlarged cross-sectional view taken along the line EE of FIG.

FIG. 8 is a load curve diagram showing the bumper structure of the automobile of the present invention.

9 is a cross-sectional view showing a mold structure during molding corresponding to a cross section taken along line XX of FIG.

FIG. 10 is a cross-sectional view showing an initial state of slide type and core type releasing.

FIG. 11 is a cross-sectional view showing a releasing state of a slide type and a core type.

FIG. 12 is a cross-sectional view showing a conventional automobile bumper structure.

13 is a load curve diagram of the automobile bumper structure shown in FIG.

FIG. 14 is a sectional view showing another example of a conventional automobile bumper structure.

15 is a sectional view taken along the line FF of FIG.

16 is a load curve diagram showing the bumper structure of the automobile shown in FIG.

FIG. 17 is a sectional view showing still another example of a conventional automobile bumper structure.

[Explanation of symbols]

 2 ... Bumper reinforcement 3 ... Bumper face 6 ... Impact absorbing part 7 ... Partition wall 8 ... Thin rib 9 ... Thick rib

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication B60R 19/18 CD

Claims (1)

[Claims] 1. A bumper structure for an automobile, which is provided in a vehicle width direction at a front end portion or a rear end portion of the automobile, wherein a bumper reinforcement formed of a resin containing glass fiber and extending in the vehicle width direction is provided for the automobile. A bumper face is provided at a front end portion or a rear end portion so as to cover the bumper reinforcement, and an impact integrally formed with the bumper face is provided between the bumper reinforcement and the bumper face. An absorbing portion is formed, the impact absorbing portion includes a partition wall, a thin rib integrally formed on the partition wall and facing the bumper reinforcement, and a thick rib integrally formed on the partition wall and extending to the bumper face side. A bumper structure for an automobile, wherein the thick ribs and the thin ribs are arranged in a row in the vehicle front-rear direction with the partition wall interposed therebetween.