JPH07186849A - Bumper reinforcing material made of aluminum alloy for automobile - Google Patents

Abstract

PURPOSE:To make performance as a bumper reinforcing material equal to or higher than that of a conventional bumper reinforcing material and to reduce a manufacturing cost. CONSTITUTION:A bumper reinforcing material 11 comprises a center beam 12 positioned at the central part in the direction of width of an automobile; and a corner beam 13 coupled to the center beam and positioned at the corner part of an automobile. The center beam 12 and the corner beam 13 are formed of an extrusion material and intercoupled in a form that the extrusion directions thereof cross each other at right angles. The center beam 12 and the corner beam 13 are an hollow extrusion material and the corner beam 13 is provided at its interior with one or two or more webs 16 extending obliquely frontward or obliquely rearward of the automobile.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bumper reinforcing material for an automobile made of an aluminum alloy for reinforcing a bumper of an automobile.

[0002]

2. Description of the Related Art Recently, aluminum alloys have come to be used for various members for automobiles in response to the demand for weight reduction of automobiles. For example, this aluminum alloy is also used as a bumper reinforcement material for automobiles.

FIG. 5 is a view showing a conventional aluminum alloy automobile bumper, and FIG. 5 (b) is a horizontal sectional view thereof.
(A) is sectional drawing by the AA line of (b). The bumper reinforcing member 6 is fixed to the front portion and the rear portion of the vehicle body by the bumper stay 7 and the supporting portion 8. A bumper cover 4 is arranged so as to surround the bumper reinforcing material 6, and a filling material 5 such as urethane is filled in the cover 4. The reinforcing member 6 connects the flange 1 arranged vertically, the flange 2 arranged in parallel to the flange 1 inside the vehicle body of the same width, and the flanges 1 and 2 together.
It is constituted by four horizontally arranged webs 3. The end portion 9 of the reinforcing member 6 is bent toward the inside of the vehicle body in order to prepare for a collision from an oblique direction with respect to the vehicle body.

Since the bumper reinforcing member thus constructed must have a certain impact resistance not only against a collision from the front of the automobile but also from a diagonal direction, as described above, It is necessary to bend the part 9 toward the vehicle body. In this case, the bending process needs to be adapted to the design of the automobile. For this reason, although it varies depending on the vehicle type, the bending radius is 200 to 300 in the vehicle type in which the aluminum alloy is used for the bumper reinforcing material.
mm is common.

[0005]

However, the end bending required for the above-mentioned aluminum alloy bumper reinforcement has a bending angle sufficient to protect the vehicle body from a diagonal collision of an automobile. In addition, it is necessary that the corner portion after processing has sufficient cross-sectional shape and material strength for impact resistance. But,
In the end bending process of the conventional aluminum alloy bumper reinforcement, the bend angle that can be achieved is limited by the cross-sectional size and material of the extruded material.

That is, it is necessary that the cross-sectional shape and the material should have sufficient performance for the central portion of the bumper, and that the weight reduction should be emphasized. Therefore, since it is necessary to give priority to the strength and weight reduction of the central portion, it is not possible to select the optimum cross-sectional shape and material for bending.

Therefore, when the material is forcibly bent in order to achieve a predetermined bending angle, cracks 10 may occur at the corners as shown in FIG. Then, the strength at the corners is significantly reduced, and the performance as a bumper cannot be maintained. In order to avoid cracking, it is possible to bend the material in the annealed state and then heat-treat it to a specified strength, or add reinforcement to the ends, but these increase the manufacturing cost. And increase in weight, which is not preferable.

The present invention has been made in view of the above problems, and the performance as a bumper reinforcing material is equal to or higher than that of the conventional one, and the manufacturing cost thereof can be reduced. The purpose is to provide wood.

[0009]

An aluminum alloy bumper reinforcement for automobiles according to the present invention comprises a center beam located in the center of the vehicle width direction and a corner beam connected to the center beam and located in the corner of the automobile. And the center beam and the corner beam are made of an extruded material and are connected in a manner that their extruding directions are orthogonal to each other.

In this case, the center beam and the corner beam are hollow extruded materials, and the corner beam has one or more webs extending diagonally forward or diagonally rearward of the automobile, and the inside of the web is formed by the webs. Can be divided into two or more hollow chambers. Further, the corner beam may be configured to integrally have a mounting portion for mounting on an automobile.

[0011]

The present inventors repeated various experimental studies to develop a reinforcing material capable of improving the collision resistance performance of the corner portion of the aluminum alloy automobile bumper reinforcing material and reducing the cost. The present invention has been completed based on the findings. That is, both the central portion and the corner portion of the bumper reinforcing member are subjected to an impact force in a direction perpendicular to the longitudinal direction thereof, as shown in FIG. In this case,
The assumed impact direction and the member length are different between the central portion and the corner portion. Therefore, from the viewpoint of impact resistance performance and weight reduction, it is preferable that the central portion and the corner portion are formed as separate members and the optimum cross-sectional shape and material are selected. For this reason, in the present invention, the center beam and the corner beam are manufactured as separate members by extrusion, and they are connected to form one reinforcing member.
In this case, the center beam and the corner beam are connected so that the extrusion directions thereof are orthogonal to each other.

In the present invention, since the corner beam and the center beam are separate members, the conventional bending process is unnecessary, and the bending angle at the corner portion of the bumper is changed by changing the extruded sectional shape of the corner beam. It can be arbitrary, and a bumper with a severe bending angle which cannot be obtained by the conventional bending method can be obtained. Further, since there is no bending process, wrinkles and cracks on the surface do not occur.

[0013]

Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a horizontal sectional view showing a bumper reinforcement member according to a first embodiment of the present invention.
[Fig. 3] is a perspective view for explaining the assembling method. As shown in FIG. 1, the bumper reinforcing member 11 has a center beam 12 arranged in the center of the front and rear portions of the automobile in the width direction, and corner beams 13 connected to both sides of the center beam 12. The corner beam 13 is located at the corner of the automobile.

The center beam 12 has a vertically arranged outer flange portion 18 similar to the conventional reinforcing member shown in FIG.
And an inner flange portion 19 and a horizontal web 17 connecting these flange portions. The center beam 12 is manufactured by extruding an aluminum alloy in its longitudinal direction.

On the other hand, in the corner beam 13, the outer flange portion 15 and the inner flange portion 14 are arranged vertically, and the flange portions 14 and 15 are connected to each other, for example, 3
The book webs 16 are arranged vertically. The surface of the web 16 is inclined with respect to the vehicle body and faces the direction to which the impact force at the time of collision is applied when the bumper is attached to the vehicle body. This corner beam 1
3 is manufactured by extruding an aluminum alloy, but it is arranged with its extrusion direction vertical,
The web 16 at one end is superposed on the center beam 12 and is connected to the center beam 12. The two are connected by fixing the connecting portion 20 to each other by means such as bolt fixing, welding or adhesion.

In the bumper reinforcing member thus constructed, the center beam 12 and the corner beam 13 are manufactured by extrusion as separate members. Then, the extrusion directions are perpendicular to each other, and they are connected to each other, and as shown in FIG. 1, they are assembled into a bumper having curved corners. In this case, the bending angle of the bumper can be arbitrarily set by changing the sectional shape of the corner beam 13. For example, by increasing the angle formed by the webs 16 with respect to each other, the outer flange portion 15 becomes significantly longer than the inner flange portion 14, and the bending angle of the bumper increases. Conversely, by reducing the angle formed by the web 16, the dimensional difference between the outer flange portion 15 and the inner flange portion 14 is reduced, and the bending angle of the bumper is reduced. Further, since the bending process is not required, the cracking of the reinforcing material due to the bending process is eliminated, and the expensive bending facility conventionally used is not necessary, and the manufacturing cost is reduced also in this respect. Furthermore, the corner beam 13 and the center beam 12 can have different cross-sectional shapes and materials, and a bumper having an optimal structure for impact resistance can be obtained. Furthermore, in the event of a collision, it is sufficient to replace either the corner beam or the center beam instead of the entire bumper, and repair costs are reduced.

Next, a second embodiment of the present invention will be described with reference to the horizontal sectional view of FIG. The bumper reinforcement member 20 of this embodiment includes a center beam 21 and a corner beam 22.
This is when the angle formed by and is larger than that in the embodiment of FIG. The reinforcing material of FIG. 1 has a corner bending angle of 20 °, but the reinforcing material of this embodiment has a corner bending angle of 40 °.
°. The corner beam 22 has an outer flange portion 24.
And the inner flange portion 23, the four webs 25 are arranged. Even if the bending angle of the bumper is large as in this embodiment, the same effect as that of the embodiment shown in FIG. 1 can be obtained.

FIG. 4 is a horizontal sectional view showing a third embodiment of the present invention. The bumper reinforcing member 30 of this embodiment is different from the other embodiments in that the corner beams 32 arranged on both sides of the center beam 31 have a stem portion 36 for attaching the bumper to the vehicle body. That is, the corner beam 32 of this embodiment has an outer flange portion 34 and an inner flange portion 33.
And the three webs 35 are arranged so as to be inclined with respect to the front of the vehicle body, and the stem portion 36 is provided so as to project inward from the substantially half inner flange portion 33 on the center beam 31 side. ing. The stem portion 36 is integrated with the corner beam 32, and when the corner beam 32 is extruded, the stem portion 36 is also formed at the same time. In this embodiment, the same effect as that of the embodiment shown in FIGS. 1 and 3 is obtained, and the stem portion for attaching the bumper to the automobile can be manufactured integrally with the corner beam 32 by extrusion molding. This also has the effect of simplifying the assembly process. The corner bending angle in this example is 30 °.

Next, the bumper reinforcing material of each of the above embodiments,
As a comparative example, an impact resistance evaluation result and a manufacturing cost evaluation result of a conventional integral type bumper reinforcing material will be described. FIG. 9 is a comparative example of the embodiment shown in FIG. 1, and the corner bending angle is 20 °. FIG. 10 is a comparative example of the embodiment shown in FIG. 3, and the corner bending angle is 40 °. FIG. 11 shows a comparative example of the embodiment shown in FIG. 4, in which the corner bending angle is 30 ° and
A separate stay portion is attached by welding. The evaluation results of these Examples and Comparative Examples are shown in Table 1 below.

[0020]

[Table 1]

The bending angle was determined as shown in FIG. 7 by the angle formed by the tangent line perpendicular to the collision direction at the center of the reinforcing member 40 and the tangent line perpendicular to the collision direction at the corners. . Further, the impact resistance is as shown in FIG.
In the pendulum collision test, the magnitude of the impact resistance load when the pendulum 41 collides was evaluated. Pendulum 41 speed is 10k
m / h, mass is 1000 kg. In the case of a collision in this range, the greater the impact resistance load, the better the impact resistance.

As shown in Table 1, in the case of Example 1 and Comparative Example 1 which have the corners bent at a relatively gentle angle, the impact resistance performance is equivalent, but Comparative Example 1 is a bending machine. Therefore, the manufacturing cost is high.

On the other hand, in the case of Example 2 and Comparative Example 2 in which the corner portion is bent at a relatively severe angle, Comparative Example 2
In the above, since the processing strain is concentrated on the bent portion, the impact resistance in the impact test is low. On the other hand, in the case of Example 2, since the bending process was not performed, the impact resistance performance commensurate with the performance of the cross section of the reinforcing material was obtained.

Further, in the case of the reinforcing member provided with the stay portion for attaching the bumper to the vehicle body, in Comparative Example 3, the stay portion manufactured in a separate process is attached to the extruded bumper reinforcing material which is bent. There is a need. On the other hand, in the case of the third embodiment, since the stay portion 36 is integrally formed with the corner beam 32, a separate process for manufacturing and attaching the stay portion is unnecessary. Therefore, the manufacturing cost of Example 3 is further reduced as compared with Comparative Example 3.

[0025]

As described above, the aluminum alloy bumper reinforcing material for automobiles according to the present invention has the same performance as the conventional reinforcing material such as impact resistance as the reinforcing material, but the manufacturing cost thereof. Can be reduced, the bending angle of the corner portion can be arbitrarily set, and the degree of freedom in vehicle design can be improved.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing the same assembling method.

FIG. 3 is a horizontal sectional view showing a second embodiment of the present invention.

FIG. 4 is a horizontal sectional view showing a third embodiment of the present invention.

5A and 5B are views showing a conventional bumper, wherein FIG. 5A is a sectional view taken along line AA of FIG. 5B, and FIG. 5B is a horizontal sectional view thereof.

FIG. 6 is a diagram showing cracks in a corner portion.

FIG. 7 is a diagram illustrating a bending angle of a corner portion.

FIG. 8 is a diagram illustrating an impact resistance test.

FIG. 9 is a view showing the shape of a conventional bumper reinforcing member (Comparative Example 1).

FIG. 10 is a view showing the shape of another conventional bumper reinforcing member (Comparative Example 2).

[Fig. 11] Still another conventional bumper reinforcing material (Comparative Example 3).
It is a figure which shows the shape of.

[Explanation of Codes] 6,11,20,30; Bumper Reinforcing Material 12,21,31; Center Beam 13,22,32; Corner Beam 13,19,23,33; Inner Flange Part 15,18,24,34 Outer flange portion 16, 25, 35; web 20; connecting portion 36; stem portion

Claims (3)

[Claims] 1. A center beam located in a central portion of a vehicle width direction and a corner beam connected to the center beam and located in a vehicle corner portion, wherein the center beam and the corner beam are made of extruded material. An aluminum alloy bumper reinforcing material for automobiles, characterized in that the extrusion directions are connected to each other at right angles. 2. The center beam and the corner beam are hollow extruded materials, and the corner beam has one or more webs extending obliquely forward or obliquely rearward of the automobile, and the inside of the web is two. The aluminum alloy automobile bumper according to claim 1, wherein the bumper is divided into the hollow chambers. 3. The bumper for an automobile made of an aluminum alloy according to claim 1, wherein the corner beam integrally has an attachment portion for attaching to an automobile.