JPH10236263A - Structure of instrument panel for airbag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of injuring the appearance without using unnecessarily expensive material or a sealing tape by contriving the shape of a door member and the shape of installation, thereby properly absorbing thermal expansion or thermal shrinkage. SOLUTION: An instrument panel for an airbag is formed by integrating as one body a skin member 4, which has a splitting part 3 at a position corresponding to the developing part of an airbag, a door member 6 facing the skin member 4, and a foam layer 7, which is formed by injecting foaming material into between both members 4 and 6. In such structure of the instrument panel, a recessed part 9 is formed on the door member 6 side toward the skin member 4 side. In this case, the thickness of, the top part 9a of the recessed part 9 is reduced, so that the thermal deformation absorbing part is formed on the door member 6 as an integrated body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag for a vehicle, in particular, an airbag for a passenger seat is housed inside in a folded state. The present invention relates to an instrument panel structure for an airbag that is split so as to be deployed forward.

[0002]

2. Description of the Related Art As shown in FIG. 8, an instrument panel for an airbag of this type generally has an H-shape in a plan view or a linear portion at a position corresponding to a deployed portion of an airbag from a groove or a relief. A split portion 11 formed into a substantially WY shape or the like in plan view by a pair of inclined portions which are respectively branched and expanded in a V-shape from both ends in the longitudinal direction of the linear portion and connected to each other. A door made of a resin plate or a metal plate of aluminum or the like fixed to a base material 15 facing the inside of the skin material 12 molded of polyvinyl chloride) or TPO (styrene-based or olefin-based thermoplastic elastomer). A foaming material such as polyurethane is injected between the material 13 and the foamed material, and the foamed material is foamed to integrally form the skin material 12, the door material 13, and the foamed layer 14.

In the instrument panel for an airbag as described above, the constituent materials of the skin material 12 and the foam layer 14 and the constituent material of the door material 13 have different coefficients of thermal expansion. The problem is that the entire instrument panel is deformed by the thermal expansion force at the time of heating or the thermal contraction force at the time of cooling caused by cooling inside the vehicle, impairing the appearance at normal times or adversely affecting the tearing performance when the airbag is inflated. There is. As a countermeasure for preventing the instrument panel from being deformed due to such thermal expansion and thermal contraction, conventionally, as a constituent material of the door material 13, a material whose thermal expansion coefficient is close to the thermal expansion coefficient of the skin material 12 or the like is used. As shown in FIG. 8, the door material 13 used is divided, and a gap S sufficient to absorb thermal expansion is provided between the divided door material portions 13a and 13b.

[0004]

However, in the case of the thermal expansion absorbing means as described above, use is made of an unnecessarily expensive component material in view of strength and performance required for the door material 13. In addition, the cost of the entire instrument panel is likely to increase. In such a case, in order to prevent the foaming material from leaking from the gap S when the foaming material such as polyurethane for forming the foam layer 14 is injected and foamed, the foaming material extends between the back surfaces of the divided door members 13a and 13b. Not only is it necessary to apply a costly and man-hour process such as attaching a sealing tape t for closing the gap S by means of a seal, or sealing the gap S with a molding die (not shown). When a part of the foaming raw material injected into the gap enters the gap S and foams, there is a problem that a molding defect such as a concave portion appears on a part of the surface of the instrument panel is likely to occur.

[0005] The present invention has been made in view of the above circumstances, and by devising the shape and mounting shape of the door material, it is possible to eliminate the need for unnecessary expensive materials and sealing tapes. It is an object of the present invention to provide an instrument panel structure for an airbag which can appropriately absorb thermal expansion and thermal contraction to overcome problems such as appearance loss.

[0006]

In order to achieve the above object, an instrument panel structure for an airbag according to the first aspect of the present invention comprises a skin material having a cleavage portion at a location corresponding to a deployment portion of the airbag. In the instrument panel structure for an airbag in which a foaming material is injected and foamed between the door material and the door material opposed thereto, and the skin material, the door material, and the foam layer are integrated, the heat deformation absorbing portion is provided on the door material side. Are integrally formed.

According to the first aspect of the present invention, the thermal expansion force at the time of heating due to irradiation of sunlight or the like and the thermal contraction force at the time of cooling due to cooling inside the vehicle are applied to the door material side. Since it is possible to absorb and relax by the expansion and contraction action of the integrally formed thermal deformation absorbing portion, it is necessary to satisfy the strength and performance requirements for the door material as a constituent material of the door material. And just use enough cheap materials,
In addition, the entire door material can be formed into an integral shape, which can prevent the use of a sealing tape or a special molding die necessary for dividing the door material and the occurrence of molding defects due to the use thereof. .

[0008] In the instrument panel structure for an airbag according to the first aspect of the present invention, the thermal deformation absorbing portion formed on the door material side has at least the door material. In the case where the top portion is partially formed of a concave portion which is thin and integrally protrudes toward the skin material side, the expansion and contraction effect accompanying the thermal expansion and heat shrinkage of the door material is smoothly performed by bending at the thin top portion, and the instrument It is possible to properly and reliably exhibit the thermal deformation prevention performance of the ment panel. At this time, as described in claim 3, the thin top of the concave portion serving as the thermal deformation absorbing portion is formed so as to face the cleavage portion of the skin material, so that the thermal expansion absorbing function is provided on the skin material side. The concave part protruding toward the door is also used as the rupture part on the door material side when the airbag is inflated, and the whole instrument panel is manufactured compared to the rupture part formed separately from the thermal deformation absorbing part on the door material side. The instrument panel can be easily formed, and even in the thermal expansion and contraction state, the displacement of the movement trajectory of the concave portion (burst portion) and the cleavage portion on the skin material side is eliminated, or is extremely reduced. It is also possible to improve the overall cleavage performance.

The instrument panel structure for an airbag according to the invention described in claim 4 is characterized in that the airbag has a cleaved portion at a location corresponding to a deployed portion of the airbag and a door material opposed to the cleaved portion. In the instrument panel structure for an airbag in which the foam material is injected and foamed to integrate the skin material, the door material, and the foam layer, a member capable of engaging with the edge of the mounting base material on the door material side. A mating piece is integrally formed, and a gap for absorbing thermal expansion is provided at an engaging portion between the engaging piece and an edge portion of the base material.

According to the fourth aspect of the present invention, the expansion and contraction force acting on the door member due to thermal expansion at the time of heating due to irradiation with sunlight or thermal contraction at the time of cooling due to cooling inside the vehicle. Can be absorbed and mitigated by the gap provided in the engaging portion between the engaging piece integrally formed on the door material side and the edge of the base material for attaching the door material, so that the door material Compared to fixing the edge to the mounting base material using bolts and nuts, the use of bolts and nuts can be omitted to reduce parts and assembly costs, as well as to heat and cool instrument panels. It is possible to properly and reliably exhibit the accompanying thermal deformation prevention performance.

Further, in the instrument panel structure for an airbag according to the invention described in claim 4, as described in claim 5, the outer periphery of the opening peripheral portion of the case for accommodating the airbag on the door material side. Is provided integrally with the wall member, and the wall member and the case are fixed to each other through a bar-shaped fixing member, so that the wall member is not fixed to the mounting base material. It is possible to prevent the door material from coming off or falling off when the airbag is inflated and deployed by fixing and holding the door material that may come off or fall off when the airbag is inflated and deployed, Further, since a bar structure is employed as a fixing means for the airbag storage case, it is possible to facilitate the entire assembling work.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a main part showing an instrument panel structure for an airbag according to a first embodiment of the present invention.
The instrument panel has a built-in airbag case 2 in which a passenger seat airbag (not shown) is stored in a folded state at a lower portion, and covers a front opening of the airbag case 2. 1 has a cleavage portion 3 such as an H-shaped shape in plan view or a substantially WY-shaped shape in plan view as described above at a location corresponding to the deployment portion of the airbag, and is made of PVC (polyvinyl chloride) or TPO (styrene). Material formed of a thermoplastic or olefin-based thermoplastic elastomer), a door material 6 made of a resin plate or a metal plate having an edge fixed to a mounting base 5 facing the material, and a skin material thereof A foaming material such as a polyurethane resin is injected into the space between the door material 4 and the door member 6 and foamed.

In the instrument panel 1 having the above-described basic configuration, the cleavage portion 3 of the skin material 4 has a groove 8 formed on the back side of the skin material 4 as shown in an enlarged view in FIG. On the other hand, a portion facing the concave groove 8 which becomes the cleaved portion 3 of the skin material 4 on the door material 6 side has an H-shape in plan view toward the skin material 4 side or a flat surface as described above. A concave portion 9 having a planar shape similar to the above-described cleavage portion 3 such as a substantially WY-shaped shape is integrally formed so as to protrude.

The thickness t1 of the top portion 9a of the recess 9 on the side of the door member 6 is changed to the thickness t0 of the other portion of the recess 9.
The heat deformation absorbing portion on the door member 6 side is formed by the thin top portion 9a.

In the airbag instrument panel structure configured as described above, the thermal deformation absorbing portion composed of the thin top portion 9a is formed on the door member 6 side facing the skin member 4, so that the solar panel is provided with the sun. When a thermal expansion force or a heat contraction force acts on the door member 6 due to heating accompanying irradiation with light rays or cooling accompanying vehicle interior cooling, the thermal expansion force or the heat contraction force is integrally formed on the door member 6 side. It can be absorbed and relaxed by the expansion and contraction effect of the thin top portion 9a of the concave portion 9 due to the bending deformation. As a result, the constituent material of the door member 6 has a larger coefficient of thermal expansion than the constituent materials of the skin member 4 and the foam layer 7, and is necessary and sufficient to satisfy the strength and performance required for the door member 6. While using an inexpensive material and forming the entire door member 6 into an integral shape without dividing it, it is possible to eliminate problems such as loss of appearance due to thermal deformation of the entire instrument panel 1.

In the case of the first embodiment, in order to exhibit the above-mentioned thermal expansion absorbing function, the recess 9 is formed so as to protrude from the door member 6 toward the cleavage portion 3 on the skin member 4 side.
It is possible to exhibit a predetermined thermal expansion absorbing function while always maintaining the position facing the cleavage portion 3 on the skin material 4 side.
The thin ridge 9a of the recess 9 is ruptured when the airbag is inflated.
The motion trajectory of the ruptured edge and the cleavage portion 3 on the skin material 4 side
In addition, it is possible to improve the tearing performance of the entire instrument panel 1 by eliminating or extremely reducing the positional deviation.

FIG. 3 is an enlarged vertical sectional view of a main part of an instrument panel structure for an airbag according to a second embodiment of the present invention. A top portion 9 of a concave portion 9 integrally formed so as to protrude toward a cleavage portion 3 from a portion facing the cleavage portion 3
a, the thickness of the top portion 9a is reduced by forming a concave groove 10 recessed on the door material 6 side, and the heat deformation absorbing portion on the door material 6 side is formed with the thin top portion 9a. It is. Since other configurations are the same as those of the first embodiment, the corresponding portions are denoted by the same reference numerals and description thereof will be omitted.

In the instrument panel 1 for an airbag according to the second embodiment, as in the case of the first embodiment, the door member 6 is heated by irradiation with sunlight or the like and cooled by cooling inside the vehicle. The thermal expansion force and heat contraction force acting on the instrument panel 1 are absorbed and relaxed by the expansion and contraction effect of the thin top portion 9a of the concave portion 9 formed integrally with the door member 6 side, and the thermal deformation of the entire instrument panel 1 is achieved. In addition, the concave portion 9 is also used as a rupture portion on the door member 6 side when the airbag is inflated, so that the tearing performance of the entire instrument panel 1 can be improved.

FIG. 4 is an enlarged longitudinal sectional view of a main part of an instrument panel structure for an airbag according to a third embodiment of the present invention. The top 9a is made thinner toward the cleaved portion 3 from the portion opposed to the cleaved portion 3 and the base portion on both sides of the recess 9 for the rupture portion formed integrally and protruding from the portion opposite to the skin material 4 side. The recesses 11, 11 having a protruding margin smaller than the recess 9 are integrally formed, and the thin-walled top portion 9 a of the recess 9 and the recesses 11, 11 on both sides form a thermal deformation absorbing portion on the door material 6 side. Things. Since other configurations are the same as those of the first embodiment, the corresponding portions are denoted by the same reference numerals and description thereof will be omitted.

In the instrument panel 1 for an airbag according to the third embodiment, the thermal expansion force and the heat contraction force acting on the door member 6 due to the heating caused by the irradiation of sunlight or the like and the cooling caused by the cooling in the vehicle or the like. The thin top portion 9a of the concave portion 9 formed integrally with the door member 6 and the concave and convex portions 11, 11 on both sides thereof absorb and relax due to expansion and contraction to prevent thermal deformation of the entire instrument panel 1, When the airbag is inflated, the airbag is ruptured at the thin top portion 9a of the concave portion 9 on the door member 6 side, so that the tearability of the entire instrument panel 1 can be secured as predetermined.

In the instrument panel structure for an airbag according to the first to third embodiments, the thermal deformation absorbing portion on the door material 6 side is formed at a position facing the cleavage portion 3 on the skin material 4 side. However, as in the fourth embodiment shown in FIG. 5, the concave portion 9 serving as the thermal deformation absorbing portion on the side of the door member 6 serves as a rupture portion of the door member 6 when the airbag is inflated. Alternatively, it may be formed separately and integrally with the protruding portion 12 protruding so as to face the cleavage portion 3 of the skin material 4.

FIG. 6 is a longitudinal sectional view of a main part of an instrument panel structure for an airbag according to a fifth embodiment of the present invention, and FIG. 7 is an enlarged perspective view of the main part of FIG. In the embodiment, a substantially inverted L-shaped engagement piece 13 that can engage with the edge 5a of the mounting base material 5 is integrally formed at a position near the entire periphery or three peripheral pieces of the door member 6. A gap 14A for absorbing thermal expansion is formed in an engagement portion between the engagement piece 13 and the edge 5a of the mounting base material 5 so that the door member 6 can be attached to the mounting base material 5 with the clearance. It is supported so as to be freely movable within a range of 14A.

On the other hand, on the door member 6 side, a wall member 15 disposed outside the periphery of the opening of the airbag case 2 is integrally provided. Are formed, and from the airbag case 2 side, U-shaped engaging portions 17 that can protrude to the outside of the wall member 15 by being inserted into the through holes 16 are formed. Is provided. Each of the U-shaped engaging portions 17 is inserted through the square-shaped through-holes 16 of the wall member 15 so as to protrude outward, and extends over the protruding portions of the engaging portions 17. The door member 6 is fixedly connected to the airbag case 2 by inserting a bar-shaped fixing member 18 into the airbag case 2.

In the instrument panel structure according to the fifth embodiment having the above-described configuration, when a thermal expansion force or a heat contraction force acts on the door member 6 due to heating accompanying irradiation with sunlight or cooling due to cooling in the vehicle, etc. The thermal expansion force and the heat contraction force are absorbed and reduced by the thermal expansion absorbing gap 14A formed in the engagement portion between the engagement piece 13 on the door member 6 side and the edge 5a of the mounting substrate 5. Door material 6
The use of bolts and nuts eliminates the use of bolts and nuts as compared with the case where the end portions of the above are fixed to the mounting base material 5 using bolts and nuts. It is possible to properly and reliably exhibit the performance of preventing heat deformation due to heating and cooling.

In the fifth embodiment, as described above, the thermal expansion absorbing gap 14A is formed in the engaging portion between the engaging piece 13 on the door member 6 and the edge 5a of the mounting base material 5. Since the door member 6 is formed and the door member 6 is not fixed to the mounting base material 5, the door member 6 may come off or fall off when the airbag is inflated and deployed. Is fixedly connected to the airbag case 2 via a bar-shaped fixing member 18, so that the door member 6 is securely prevented from coming off or falling off when the airbag is inflated and deployed. By adopting, it is possible to facilitate the entire assembly work

Although not described in each of the above embodiments, as the thermal expansion absorbing means on the door 6 side, the concave portion 9 as described in the first to fifth embodiments, It is a matter of course that a thermal expansion absorbing gap 14A formed at an engagement portion between the engagement piece 13 and the edge 5a of the mounting base 5 may be provided.

[0027]

As described above, according to the first to third aspects of the present invention, it is necessary and sufficient to satisfy strength and performance requirements for the door material as a constituent material of the door material. The door material does not need to be divided and the whole is made into an integral shape.The thermal expansion force at the time of heating due to irradiation with sunlight and the heat contraction force at the time of cooling due to cooling inside the vehicle are applied to the door material side. Since it is possible to absorb and relax by the expansion and contraction action of the formed thermal deformation absorbing portion, the entire instrument panel can be easily and inexpensively manufactured by omitting unnecessary use of expensive materials and sealing tapes. In addition, while preventing the occurrence of molding defects such as dents, it is possible to properly absorb thermal expansion and thermal shrinkage, and to effectively overcome problems such as appearance loss due to thermal deformation of the instrument panel.

In particular, as described in claim 3, by forming the concave portion at the thin top serving as the thermal deformation absorbing portion so as to face the cleavage portion of the skin material, it is provided on the skin material side for the thermal expansion absorbing function. The concave part protruding toward the door is also used as the rupture part on the door material side when the airbag is inflated, and the whole instrument panel is manufactured compared to the rupture part formed separately from the thermal deformation absorbing part on the door material side. In addition to making it easier, even in the state of thermal expansion or thermal contraction, the displacement of the movement trajectory of the concave portion (ruptured portion) from the cleavage portion on the skin material side is eliminated, or the instrument is minimized. The tearing performance of the entire panel can also be improved.

According to the fourth and fifth aspects of the present invention, the expansion and contraction force acting on the door material due to thermal expansion at the time of heating accompanying irradiation with sunlight or the like and thermal contraction at the time of cooling accompanying cooling inside the vehicle, Since it is possible to absorb and relax the gap formed in the mounting portion between the door material side and the base material for mounting the door material, it is possible to use bolts and nuts as the mounting base material at the edge of the door material. In addition to reducing the use of bolts and nuts when compared to the case of fixing, the cost of parts and assembly can be reduced, and the performance of preventing heat deformation due to heating and cooling of the instrument panel can be properly demonstrated. be able to. Further, the door material that is free with respect to the mounting base material along with the formation of the gap is fixedly connected to the airbag case via a bar-shaped fixing member, so that the door material is inflated and deployed when the airbag is inflated and deployed. Blow-off can be reliably prevented, and the overall assembly operation can be facilitated by adopting the bar structure.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part showing an instrument panel structure for an airbag according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is an enlarged vertical sectional view of a main part showing an instrument panel structure for an airbag according to a second embodiment of the present invention.

FIG. 4 is an enlarged vertical sectional view of a main part showing an instrument panel structure for an airbag according to a third embodiment of the present invention.

FIG. 5 is an enlarged vertical sectional view of a main part showing an instrument panel structure for an airbag according to a fourth embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of a main part of an instrument panel structure for an airbag according to a fifth embodiment of the present invention.

FIG. 7 is an enlarged perspective view of a main part of FIG. 6;

FIG. 8 is a longitudinal sectional view of a main part of a conventional instrument panel structure for an airbag.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Instrument panel 2 Airbag case 3 Cleavage part 4 Skin material 5 Mounting base material 5a Edge of mounting base material 5 Door material 7 Foaming layer 9 Concave part 9a Thin top part of concave part 9 (for heat deformation absorbing part) Example) 11 concave portion (example of thermal deformation absorbing portion) 13 engaging piece 14 thermal expansion absorbing gap 15 wall member 18 bar-shaped fixing member

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B29L 31:58 (72) Inventor Masahiko Yanagihara 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (5)

[Claims] 1. A foaming material is injected and foamed between a skin material having a cleaved portion at a position corresponding to a deployment portion of an airbag and a door material facing the same, and the skin material, the door material and the foam layer are formed. An instrument panel structure for an airbag, wherein a thermal deformation absorbing portion is integrally formed on the door material side in an integrated instrument panel structure for an airbag. 2. The airbag according to claim 1, wherein at least a part of the door member has a thin-walled concave portion that is integrally formed and protrudes toward the skin member as the thermal deformation absorbing portion. Instrument panel structure. 3. The instrument panel structure for an airbag according to claim 2, wherein a thin top portion of the concave portion serving as the thermal deformation absorbing portion is formed so as to face a cleavage portion of the skin material. 4. A foaming material is injected and foamed between a skin material having a cleaved portion at a location corresponding to a deployment portion of an airbag and a door material opposed thereto, and the skin material, the door material and the foam layer are formed. In an integrated instrument panel structure for an airbag, an engaging piece engageable with an edge of a mounting base is integrally formed on the door material side, and the engaging piece and an edge of the base are integrally formed. An instrument panel structure for an airbag, wherein a gap for absorbing thermal expansion is provided at an engagement portion with the portion. 5. A door member is provided integrally with a wall member disposed outside a peripheral edge of an opening of a case for accommodating an airbag on a side of the door member. The instrument panel structure for an airbag according to claim 4, wherein the instrument panel is fixedly connected to the instrument panel via an airbag.