JP2000335348A - Air bag door structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the management and man-hours for molding of a recessed streak in a scheduled part for rupturing an air bag door by comprising two layers consisting of a reverse surface layer of a low elongative material and a surface layer of a highly elongative material integrally formed onto the reverse surface layer with each other. SOLUTION: The surface skin of an instrument panel having an air bag door integrally provided on the surface skin thereof is formed of two layers having elongations different from each other and consisting of a reverse layer 6 of a low elongative material formed on an urethane foam layer 5 on a base material insert 4 and a surface layer 7 of a highly elongative material integrally formed onto the reverse layer 6 with each other. The surface layer 8 and reverse layer 6 of a scheduled part for rupturing the air bag door 2 are molded into a recessed streak 8. According to such a structure, the air bag 2 can be cut only by its expanding pressure, namely, by the material characteristics of elongations of the both layers different from each other, or the reverse layer 6 consisting of the low elongative material. Accordingly, the management and inspection of the bottom thickness of the recessed streak 8 can be dispensed with to improve the productivity and reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a door structure of an airbag provided in an instrument panel.

[0002]

2. Description of the Related Art An airbag is provided as a means for protecting an occupant in the event of an automobile collision. The airbag is built in the center of the steering wheel on the driver side, and is installed inside the instrument panel 1 near the glove box 30 on the assistant side, as shown in FIG. This assistant side airbag 3 is shown in FIG.
As shown in the figure, the base insert 4 constituting the instrument panel 1 having the urethane foam layer 50 which is a safety pad between the base insert 40 and the skin 70.
0 is installed in the lower space. When a collision is detected by the sensor, the inflator ignites to generate required gas to inflate the airbag 3, and the inflation pressure of the airbag 3 causes the airbag door 20 formed on the instrument panel 1 to inflate. And swells out of the instrument panel 1 between the assistant occupant and the windshield to protect the assistant occupant.

As shown in FIGS. 6 and 7, the structure of the conventional airbag door 20 which is torn by the inflation pressure of the airbag 3 has a groove 80 (slit) where the airbag door 20 is torn. The base insert 40 is provided with a fragile portion 90 formed by a concave groove at a portion corresponding to the concave streak 80.

[0004]

The airbag door 2 described above.
As shown in FIG. 7, a ridge 80 (slit) at a portion where the ridge 0 is to be split is formed by simultaneously forming a skin B having a thickness B by slash molding. By zero clearance. The thickness of the bottom of the recess 80 is reduced to 0.3 mm in order to improve the cut at the time of tearing due to the inflation pressure of the airbag door 3. It requires many man-hours such as inspection.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an airbag door structure which reduces the number of man-hours and the number of man-hours required for forming a groove at a portion where the airbag door is to be split.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an airbag provided integrally with a skin of the instrument panel, which is torn by the inflation pressure of an airbag provided in the instrument panel. A door, wherein the skin of the instrument panel is formed by integrating a back surface layer made of a material having a small elongation on a urethane foam layer on a base material insert and a surface layer made of a material having a large elongation on the back surface layer. The airbag door is formed of two layers having different amounts of elongation, and a concave stripe is formed in the front surface layer and the rear surface layer of the portion of the airbag door to be split.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes an instrument panel, and 2 denotes an airbag door provided on the assistant side of the instrument panel 1. The airbag door 2 is provided integrally with the skin of the instrument panel 1. As shown in FIG. 2, in the space inside the instrument panel 1 immediately below the airbag door 2, as shown in FIG.

In the present invention, the skin of the instrument panel 1 in which the airbag door 2 is provided integrally with the skin of the instrument panel 1 is made of a material having a small extension on the urethane foam layer 5 on the base insert 4. Back layer 6
And a surface layer 7 made of a material having a large elongation on the back surface layer 6 and integrated into two layers having different elongation amounts.
And the back layer 6 are formed into concave stripes 8 (slits), and the hinge that is bendable between the base insert 4 and the urethane foam layer 5 at a position where the airbag door 2 is split and becomes a deployment base. The plate 10 is interposed. The base insert 4 is provided with a fragile portion 9 formed by a concave groove at a portion corresponding to the concave streak 8.

The material of the base insert 4 is a synthetic resin material such as ASG, PPG, PP, etc., which is conventionally used generally. Further, a urethane foam layer 5 serving as a safety pad is also generally used.

In view of this, the back layer 6 made of one of the two low-elongation materials, ie, the back layer 6 made of the low-elongation material and the front layer 7 made of the high-elongation material, which is a feature of the present invention. For example, foamed vinyl chloride 6 is used, and the other surface layer 7 made of a material having large elongation uses, for example, vinyl chloride (PVC).

When the surface layer 7 is formed as a two-layer structure cross section of the back layer 6 and the surface layer 7, a reservoir tank structure having a partition plate so that powder of slash skin does not adhere to the convex portion of the electroforming mold is formed. By molding the surface layer 7 together with the concave stripes 8 and then forming the second back layer 6, it is possible to realize the production of a skin having a two-layer integrated cross section having different elongation. The clearance of the surface layer 7 in the concave stripe 8 is made zero by the foaming pressure of the urethane foam layer 5.

The flexible hinge plate 10 interposed between the base insert 4 and the urethane foam layer 5 is made of a thin plate made of iron or aluminum.

As described above, the present invention has a two-layer structure in which the back layer 6 made of a material having a small elongation and the surface layer 7 made of a material having a large elongation have different elongation amounts. Since the airbag 2 is cut only by the inflation pressure of the airbag 2 by the back layer 6 made of a material having a small elongation, the thickness of the bottom of the groove 8 for improving the cut of the groove 8 can be stably obtained, and the material characteristics can be improved. If only this is grasped, the management and inspection of the thickness of the bottom of the concave streak 8 become unnecessary, and the productivity and reliability are improved.

Further, since the clearance between the concave stripes 8 is made zero by the foaming pressure of the urethane foam layer 5, it is not necessary to consider the color of the material of the second rear surface layer 6, etc. Since 6 serves to stop the urethane foam layer 5 from urethane, a separate member of the urethane stop tape and a step of applying the urethane stop tape are not required.

Further, the airbag door 2 which is torn by the inflation pressure of the airbag 3 is formed by a thin bendable hinge plate 10 made of iron or aluminum on one side of the airbag door 2 and the airbag door 2 and the instrument panel. 1 and thus are opened as shown in FIG. 4 and FIG.

[0016]

As described above, according to the present invention, two layers having different elongation amounts are obtained by integrating a back surface layer made of a material having a small elongation and a surface layer made of a material having a large elongation on the back surface layer. Of the airbag door, which is provided integrally with the skin of the instrument panel, formed on the front surface layer and the rear surface layer by forming a concave stripe on the front surface layer and the back surface layer, whereby the mutual characteristics of the two layers having different elongation amounts are different. The thickness of the bottom of the concave streak for improving the cut of the concave streak can be obtained stably,
It is not necessary to control and inspect the thickness of the bottom portion of the concave streak, thereby improving productivity and reliability. Further, since the second back surface layer serves as a urethane stopper for the urethane foam layer, a separate member of the urethane stopper tape and a step of applying the urethane stopper tape are not required, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of an instrument panel having an airbag door according to the present invention.

FIG. 2 is a sectional view of a main part of the present invention.

FIG. 3 is an enlarged view of a part viewed from an arrow A in FIG. 2;

FIG. 4 is a sectional view showing a main part of the airbag door according to the present invention in an open state;

FIG. 5 is a perspective view showing an airbag door opening state of the present invention.

FIG. 6 is a perspective view showing a conventional airbag door.

FIG. 7 is a sectional view of a main part of a conventional airbag door.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Instrument panel 2 Airbag door 3 Airbag 4 Base material insert 5 Urethane foam layer 6 Back layer 7 Surface layer 8 Concave stripe 9 Weak part 10 Hinge plate

Claims (1)

[Claims] An airbag door provided integrally with a skin of the instrument panel, which is opened by an inflation pressure of an airbag provided in the instrument panel, wherein the skin of the instrument panel is a base material insert. The airbag door of the airbag door, comprising a back layer made of a material having a small extension on the upper urethane foam layer and a surface layer made of a material having a large extension on the back layer, the two layers having different elongations. An airbag door structure, characterized in that a concave streak is formed in the front surface layer and the back surface layer of a portion to be split.