JPH04238725A - Impact beam for automobile door - Google Patents

Abstract

PURPOSE:To obtain an automobile door impact beam made of integrally molded high tensile steel plate having no warp in both end parts and very high dimensional accuracy. CONSTITUTION:An impact beam 20 for a front side door is formed by press work of a band, consisting of a high tensile steel plate, and constituted of a pipe-shaped beam part 22 of circular section and bracket parts 24, 26 formed in lengthwise direction both end parts of this beam part 22. These bracket parts 24, 26 are formed in a fan shape respectively with a side of the beam parts 22 serving as a pivot, and bead 28 is provided to reach the beam part 22 from in the vicinity of mounting parts 24A, 26A of the respective bracket parts 24, 26 and to a position of advancing a little into the beam part 22.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact beam for an automobile door, which is installed inside the door of an automobile and is used to protect occupants by preventing the door from being damaged inward in the event of a side collision.

0002

[Prior Art] Conventionally, when a load is applied to the side of an automobile from the outside in the vehicle width direction, the outer panel of the door may deform inward in the vehicle width direction. An impact beam for automobile doors is known, in which a reinforcing member made of steel pipes capable of withstanding lateral loads is bridged along the horizontal direction of the door (Utility Model No. 52-112025).
Publications, etc.).

As shown in FIG. 18, these impact beams 80 for automobile doors use a beam material 82 that is lightweight and has a flexible pipe cross section that can absorb relatively large impact energy. There is.

However, as shown in FIG. 18, this automobile door impact beam 80 includes a beam material 82 having a lightweight and high-strength pipe cross section, and a bracket 84 for fixing the beam material 82 to the door. ,
86 are connected to each other at welded portions 88 and 90, respectively. For this reason, the impact beam 80 for an automobile door has disadvantages in that the productivity decreases due to the welding work, resulting in an increase in cost, and the welded parts 88 and 90 increase the weight.

[0005] As a means to improve these problems, it is conceivable to manufacture the beam part and the bracket part by integral molding using a recently developed high-tensile steel plate (not known yet).

However, as shown in FIG. 19(A), in an automobile door impact beam 92 in which the beam part and the bracket part are manufactured by integral molding, the beam part 92A is a pipe cross section and the mounting part is a flat part. Part 9
2B, it is necessary to provide a gradually changing portion 92C in which the thickness D gradually decreases to ensure a gap with the door glass. Further, the tensile strength and yield stress of the high tensile strength steel plate constituting this automobile door impact beam 92 are extremely high. Therefore, in the process of manufacturing this automobile door impact beam 92 by press working, as shown in the imaginary line in FIG.
(B) An impact beam 92 for an automobile door manufactured with warping upward (in the direction of arrow A in FIG. 19(B))
There was a problem in that the dimensional accuracy of the mounting part 92B of the mounting part 92B deteriorated, and it was thought that integral molding was impossible.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned facts, the present invention aims to provide an impact beam for an automobile door made of an integrally molded high-tensile steel plate, which has no warpage at both ends and has extremely high dimensional accuracy.

[0008]

[Means for Solving the Problems] The invention as set forth in claim 1 is an impact beam for an automobile door formed by pressing a band made of a high-tensile steel plate, the impact beam having flat bracket portions formed at both ends. , a tubular beam portion formed continuously and integrally between these bracket portions, and a bead extending from the bracket portion to the beam portion.

[0009]

[Operation] According to the invention as set forth in claim 1, the bead reaches from the flat bracket portions formed at both ends of the impact beam for an automobile door to the tubular beam portion formed continuously and integrally between the bracket portions. It is provided. for example,
The bead extends linearly from the bracket part in the longitudinal direction of the impact beam for an automobile door, and its end reaches the beam part. Therefore, when an impact beam for an automobile door is press-molded, this bead acts as a beam and prevents warping that would otherwise occur in the bracket portion. Therefore, it is possible to obtain an impact beam for an automobile door made of an integrally molded high-tensile steel plate that has no warpage at both ends and has extremely high dimensional accuracy.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of an impact beam for an automobile door according to the present invention will be described below with reference to FIGS. 1 to 10.

As shown in FIG. 2, the front side door 10 of the automobile includes a front side door outer panel 12.
and a front side door inner panel 14, which have a box-shaped cross section as in the conventional case, and a front side door outer panel 12 and a front side door inner panel 1.
The front end edge, rear end edge and lower end edge of the front side door outer panel 12 are folded back to the front side door inner panel 14, respectively, and are firmly connected to each other. As shown in FIG. 3, the upper edges 12A and 14A of the front side door outer panel 12 and the front side door inner panel 14 are bent to face each other in a substantially U-shape, and the front side door outer panel 1
2 and the front side door inner panel 14 is provided with an opening 16 through which a front side window glass (not shown) can enter and exit.

As shown in FIG. 4, shelf portions 14B and 14C are provided substantially uniformly in the vertical direction at the front and rear portions of the front side door inner panel 14. Both longitudinal ends of an impact beam 20 for a front side door as an impact beam for an automobile door are fixed to the parts 14B and 14C, respectively.

As shown in FIG. 1, this front side door impact beam 20 is formed by pressing a band made of a flat high-tensile steel plate, and has a circular cross section. It is composed of a tubular beam section 22 and flat bracket sections 24 and 26 formed at both ends of the beam section 22 in the longitudinal direction. The beam part 22 has a joint part 22A where the edges of both ends of the flat plate abut against each other,
This joint portion 22A is joined by general welding such as arc or plasma welding, or by plastic deformation such as pressure welding.

[0014] Also, the part of the joint portion 22A that is actually connected is the front side door impact beam 2.
In the case of a pipe cross-sectional shape with a constant thickness with continuous zeros, a region S1 in the center of the beam portion 22 that receives the load in a side collision,
These are regions S2 and S3 at both ends of the beam section 22,
By combining these basins S1, S2, and S3, the function as an impact beam for a door can be fully fulfilled. Therefore, as shown by the imaginary line in FIG. 1, a gap 23 may be provided at a portion other than the joint portion.

[0015] The bracket parts 24 and 26 are fan-shaped with the beam part 22 side being the key point, and the ends of the bracket parts 24 and 26 are arranged so that the joint part 22A of the front side door inner panel 14 is connected to the front side. Mounting parts 24A and 26A are provided toward the door outer panel 12 side for fixing to the shelf parts 14B and 14C. Further, the bracket parts 24 and 26 have mounting parts 24A and 26A, respectively.
A bead 28 is provided to reach the beam part 22 from the vicinity of and to a position slightly entering the beam part 22.

As shown in FIG. 3, the front side door impact beam 20 has a joint portion 22 of the beam portion 22.
A is fixed so as to face the front side door outer panel 12 side (outside in the vehicle width direction), and the continuous plate part, that is, the non-seamed part faces the front side door inner panel 14 side (
It is fixed so that it faces (inward in the vehicle width direction). Therefore,
When a load is applied to the front side door impact beam 20 from the outside in the vehicle width direction, the different structure caused by welding or plastic deformation of the joint portion 22A becomes compressive deformation side, so that the conventional pipe structure door impact It is designed to satisfy the same intensity as a beam.

Furthermore, the bead 28 is protruded toward the inside of the front side door impact beam 20, that is, toward the front side door outer panel 12, so that the bead 28 does not reduce the gap with the door glass.

The operation of this embodiment will be explained below. When manufacturing the front side door impact beam 20 of this embodiment, as shown in FIG.
By pressing with an upper mold 32 and a lower mold 34 having the cross-sectional shape shown in FIG.
A bead 28 is formed at both ends in the longitudinal direction.
form. Next, as shown in FIG. 7, the portion of the band 30 that will become the beam portion 22 is pressed into a U-shape using an upper mold 36 and a lower mold 38 shown in FIG. Further, as shown in FIG. 9, a portion of the metal band 30 that will become the beam portion 22 is pressed with an upper mold 40 and a lower mold 42 shown in FIG. 10 to form a tubular beam portion 22.

Therefore, in the press working for forming the tubular beam portion 22, the bracket portions 24 and 26 have the shape shown in FIG.
9(B), when a warp is about to occur in the direction of arrow A, the beads 28 formed in advance at both longitudinal ends of the strap 30 act as beams against the warp, and the bracket portion 24, 26 to prevent warping that is about to occur. Therefore, it is possible to obtain an impact beam for an automobile door made of an integrally molded high-tensile steel plate, in which the bracket portions 24 and 26 are free from warping and have extremely high dimensional accuracy.

In this embodiment, the bead 28 is formed into a straight line extending in the longitudinal direction of the front side door impact beam 20, but instead of this, as shown in FIG. The side (26A side is not shown) is divided into two branch parts 46A and 46B, and the bending strength of the bracket parts 24 and 26 is further increased to prevent warping that occurs in the bracket parts 24 and 26. Also good. In addition, as shown in FIG. 12, the mounting portions 24A and 26A sides of the bead 48 (the 26A side is not shown) are divided into three branch portions 48A, 48B, and 48C to further increase the strength of the bracket portions 24 and 26. Then, the bracket parts 24, 2
It is also possible to prevent the warping that occurs in the case of 6.

Next, a second embodiment of the impact beam for an automobile door according to the present invention will be described with reference to FIGS. 13 and 14.

[0022] The same members as those in the first embodiment of the present invention are designated by the same reference numerals and their explanations will be omitted.

As shown in FIGS. 13 and 14, a reinforcing pipe 50 having a wall thickness greater than that of the beam portion 22 is fixed to a substantially central portion in the longitudinal direction of the beam portion 22 of the front side door impact beam 20. This increases the strength of this area. Therefore, the thickness of the plate material constituting the front side door impact beam 20 can be made thinner than that of the first embodiment, and the weight can be further reduced compared to the first embodiment. Furthermore, in order to fully function as an impact beam for doors, the seam 2
The parts 2A to be actually connected may be the ranges S4 and S5 of the parts corresponding to both ends 50A and 50B of the reinforcing pipe 50 and the ranges S2 and S3 of both ends of the beam part 22, and compared to the first embodiment, welding is required. The range can be reduced and productivity can be improved. Further, as shown in FIG. 14, the outer diameter R2 of the reinforcing pipe 50 is relative to the inner diameter R1 of the beam portion 22.
is made smaller and has play. Therefore, even if the inner diameter R1 of the beam portion 22 and the outer diameter R2 of the reinforcing pipe 50 vary, the joint portion 22A can be brought into close contact.

Note that in this embodiment, the beam section 22
However, instead of this, as shown in FIG. 15, only the insertion portion of the reinforcing pipe 50 has a large diameter portion 22D, and the vicinity of the bracket portions 24 and 26 have small diameter portions 22E and 2, respectively.
2F may have a structure in which gradually changing portions 22G and 22H are provided between the large diameter portion 22D and the small diameter portions 22E and 22F. In this case, displacement of the reinforcing pipe 50 can be prevented and the weight can be reduced. can be achieved.

Furthermore, in this embodiment, as shown in FIG. 14, the outer diameter R2 of the reinforcing pipe 50 is made smaller than the inner diameter R1 of the beam portion 22.
As shown in , the inner circumferential length of the beam portion 22 may be set shorter than the outer circumferential length of the reinforcing pipe 50, and a gap 52 may be intentionally provided at the joint portion 22A of the beam portion 22. In this case, the gap 52, the joint portion 22A of the beam portion 22
When welding by arc welding, the reinforcing pipe 50 can be fixed inside the beam part 22 at the same time, and productivity can be improved.

In each of the above embodiments, an example was explained in which the impact beam for an automobile door of the present invention was applied to the impact beam 10 for a front side door, but as shown in FIG. The impact beam can also be applied to the impact beam 54 for a rear side door by making the shapes of the bracket parts 54A and 54B correspond to the mounting part of the rear side door.

[0027]

As described above, the present invention has the excellent effect that it is possible to obtain an impact beam for an automobile door made of an integrally molded high-tensile steel plate, which has no warpage at both ends and has extremely high dimensional accuracy.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an impact beam for an automobile door according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a front side door to which the impact beam for automobile doors of the first embodiment of the present invention is applied.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 2;

FIG. 5 is a perspective view showing the shape of the impact beam for an automobile door according to the first embodiment of the present invention after its end is bent.

FIG. 6 is a sectional view taken along line 6-6 in FIG. 5;

FIG. 7 is a perspective view showing the shape of the impact beam for an automobile door according to the first embodiment of the present invention after U-bending.

FIG. 8 is a sectional view taken along line 8-8 in FIG. 7;

FIG. 9 is a perspective view showing the shape of the impact beam for an automobile door according to the first embodiment of the present invention after O-bending.

10 is a sectional view taken along the line 10-10 in FIG. 9. FIG.

FIG. 11 is a perspective view showing an end portion of an impact beam for an automobile door according to another example of the present invention.

FIG. 12 is a perspective view showing an end portion of an impact beam for an automobile door according to another example of the present invention.

FIG. 13 is a perspective view showing an impact beam for an automobile door according to a second embodiment of the present invention.

14 is a sectional view taken along the line 14-14 in FIG. 13. FIG.

FIG. 15 is a perspective view showing an impact beam for an automobile door according to another example of the present invention.

16 is a sectional view taken along line 16-16 in FIG. 15. FIG.

FIG. 17 is a perspective view showing an impact beam for an automobile rear side door according to the present invention.

FIG. 18 is a perspective view showing a conventional impact beam for an automobile door.

FIG. 19 (A) is a perspective view illustrating warping when an impact beam for an automobile door is integrally molded, and (B)
is a cross-sectional view taken along the line BB in Figure (A).

[Explanation of symbols]

20 Impact beam 2 for front side door
4, 26 Bracket parts 24A, 26A Mounting parts 28, 46, 48 Bead

Claims (1)

[Claims] Claim 1: An impact beam for an automobile door formed by pressing a band made of high-strength steel plate,
An automobile characterized in that it has flat bracket parts formed at both ends, a tubular beam part formed continuously and integrally between these bracket parts, and a bead extending from the bracket part to the beam part. Impact beam for doors.