JP2001199302A - Air bag door - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag door generating no large inertia energy for unfolding by cleavage and simultaneously crushable at motor vehicle cassation time. SOLUTION: This air bag door is provided with a lid part 10 being installed on a core material of an instrument panel, laminating a cushion layer and the skin on the surface in this order and unfolding by tearing the cushion layer and the skin by swelling of an air bag and a leg part 17 extending below the lid part 10 and installing the air bag device, and the lid part 10 and the leg part 17 are integrally molded by olefin type thermoplastic elastomer to be installed on the core material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instrument panel mounted on a core material, a cushion layer and a skin are sequentially laminated on the surface of the instrument panel, and the cushion and the skin are broken by airbag expansion. Related to airbag doors.

[0002]

2. Description of the Related Art A conventional airbag door closes an opening provided in a core material of an instrument panel, and is expanded by expansion of an airbag when an automobile receives an impact such as a collision. And a leg extending downward from the lid and attached to an airbag device (airbag case) in which an airbag and a gas generator are stored.

The lid portion is provided with a U-shaped or H-shaped notch in a square plate, and the U-shaped or H-shaped notch is formed.
The letter-shaped notch allows the door to be opened to one side or both sides. As the lid portion that is deployed by the inflation of the airbag, one that is usually formed using an iron plate or an aluminum plate as a base material is used.

[0004]

However, when a metal plate such as an iron plate or an aluminum plate is used for the lid portion, a large inertial energy is generated when the lid portion is split and deployed. Further, if a metal plate such as an iron plate or an aluminum plate is used for the lid portion of the airbag door, the lid portion must be removed from the instrument panel at the time of scrapping to be simultaneously crushed and cannot be treated as waste plastic.

[0005] Further, as shown in Japanese Patent Application Laid-Open No. 7-96811, an expandable lid portion of a conventional airbag door has an outer frame surrounding the outer circumference of the expandable portion. Structures that are connected to parts are widely used. Therefore, the deployment shape of the airbag door is limited by this outer frame. For example, even when the airbag door is opened in both directions, the airbag door can be deployed only in an H shape within the frame because of the outer frame. Did not.

Accordingly, a main object of the present invention is to provide an airbag door which does not generate large inertial energy when it is split and can be simultaneously crushed when scrapped. Another object of the present invention is to use the entire lid for deployment, so that the deployment shape can be freely set to a certain extent by changing the lid shape over a wide range, and the degree of freedom in the design and design of the instrument panel can be increased. It is to provide an airbag door which can be increased.

[0007]

According to a first aspect of the present invention, there is provided an instrument panel comprising: a core member of an instrument panel; a cushion layer and a skin layer are sequentially laminated on the core member; A lid portion that breaks and expands the cushion layer and the skin, and a leg portion that extends below the lid portion and attaches an airbag device, wherein the lid portion and the leg portion are olefin-based thermoplastic elastomers It is an airbag door which is attached to the core material as an integral member molded with the above. With this configuration, the entire airbag door is formed of resin, and the weight of the airbag door can be reduced. When the airbag is inflated, the lid portion of the airbag door can be deployed without generating large inertial energy. be able to. Also, by using an olefin-based thermoplastic elastomer (hereinafter, referred to as TPO) for the airbag door, if all the components such as the core material of the instrument panel, the cushion layer, and the skin are made of olefin-based resin, the airbag can be used. It is the same material as the bag door.

According to a second aspect of the present invention, the leg portion has a rectangular frame shape, and the lid portion has the first two opposing sides of the quadrangular frame as supporting points, and the other opposing second fins. It is a plate shape integrally attached to the leg portion so as to be able to be separated from the side, extends over the entire width along a line between the first two sides, and is inflated by inflation of the airbag. 2. The airbag according to claim 1, wherein a groove is provided that divides the entire lid into two parts and deploys the lid in a two-sided manner. 3. With this configuration, the entire lid portion can be opened in both directions using the first two sides of the leg portion as support points, and the size and shape of the instrument panel can be reduced as compared with the case where the lid frame of the airbag door is provided. At the same time, it is possible to form the lid part, and the design and design restrictions of the instrument panel are reduced.

According to a third aspect of the present invention, at least one open end of the surface of the lid portion which is open and closed,
3. The airbag door according to claim 2, further comprising a blade protruding substantially parallel to the second two sides and configured to break the skin and the cushion layer. 4. With this configuration, when the lid portion is expanded by the inflation of the airbag, the blade portion acts, and the cushion layer and the skin of the instrument panel are provided on the core material with the unprocessed skin mainly at a low temperature. It can be broken and split along the cut edge.

According to a fourth aspect of the present invention, there is provided the airbag door according to the second aspect, wherein the lid portion and the core member are attached by fitting. With this configuration, it is not necessary to use a metal fixing member such as a bolt when attaching the lid portion to the core member.

According to the fifth aspect of the present invention, the olefin thermoplastic elastomer has a glass transition temperature of -50 to-
The airbag door according to any one of claims 1 to 4, which is in a range of 60C. With this configuration, the glass transition temperature is lowered, and the airbag door can be reliably deployed when the airbag is inflated even in a low-temperature environment.

According to a sixth aspect of the present invention, there is provided a quadrangular frame-shaped leg to which the airbag device is attached, and a pair of first and second opposite sides of the quadrangular frame serving as support points, and a pair of remaining two opposite sides. A plate-shaped lid portion integrally attached to the leg portion so that the airbag can be separated, and the lid portion is provided over the entire width along a line between the first two sides. A resin airbag door comprising: a groove portion that divides the entire lid portion into two parts by bulging and expands the lid portion in a two-sided manner. According to this configuration, since the airbag door is made of resin, the airbag door can be reduced in weight, does not generate large inertial energy when the airbag door is deployed, and the entire surface of the lid portion can be easily deployed in a double-opening manner. Become.
In addition, the lid can be formed according to the size and shape of the instrument panel, compared to the case with the lid frame of the airbag door, which reduces restrictions on the design and design of the instrument panel. Is done.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An instrument panel integrated with an airbag door according to an embodiment of the present invention will be described with reference to the drawings. The airbag door according to the present invention is not limited to the following embodiment.

FIG. 1 is an overall perspective view of an airbag door according to the present embodiment, FIG. 2 is a schematic cross-sectional view taken along line AA of the airbag door in FIG. 1, and FIG. FIG. 4 is a schematic cross-sectional view taken along the line BB of the door attached to the instrument panel, FIG. 4 is an overall perspective sectional view showing a state where the door is attached to the instrument panel, and FIG. 5 is an overall perspective view of the instrument panel. FIG.

The airbag door 2 in the present embodiment is
As shown in FIG. 1, a rectangular plate-shaped lid portion 10 that is developed by inflation of the airbag 22 (see FIG. 3), and a rectangular frame shape corresponding to the square plate, which extends below the lid portion 10. And a leg 17 having a first two sides 171 in the longitudinal direction and a second two sides 172 in the short direction.

The first side of the leg 17 is provided on the back side of the lid 10.
The groove 13 is provided between the two sides 171 and extends over substantially the entire width of the lid 10, and serves as a starting point when the lid 10 is unfolded. Thereby, the lid 10
Has a double opening structure of a front airbag lid 11 and a rear airbag lid 12 located on the front side of the vehicle. As shown in FIG. 3, the groove 13 has a V-shaped cross section opened toward the airbag case 21, and is formed over substantially the entire width of the lid 10.

A portion of the rear side of the lid 10 along the first two sides 171 of the leg 17 is
There are provided two hinge portions 14a and 14b for rotatably supporting the. As a result, the lid portion 10
Can be developed using the two sides 171 as support points.

As shown in FIG. 1, each hinge 14
a and 14b are formed integrally with the front airbag grid 11 and the rear airbag grid 12, respectively, and rotatably support both ends of the airbag grids 11 and 12 with respect to the leg 17. These hinge portions 14a, 14
“b” is disposed inside the leg 17 so as to face the groove 13. The hinge portions 14a and 14b are open to the airbag case 21 side, are formed in a trapezoidal cross section toward the airbag lids 11 and 12 side, and have the entire width of the airbag lids 11 and 12, respectively. Extends to the side. However, as long as the lid portion 10 can be rotated and deployed, the hinge portions 14a and 14b need not have a trapezoidal cross-sectional shape, and may have a semicircular or rectangular shape. The shape does not have to be cut into the lid portion side as in the embodiment.

As is clearly shown in FIG.
A notch 18 is provided in a joint portion between the 0 and the leg portion 17 and parallel to the second two sides 172 so that the air bag can be separated when the airbag is inflated and deployed. This makes it possible to reliably spread the entire surface of the lid 10 without impairing the integrity of the resin of the lid 10 and the leg 17.

Further, at both ends in the longitudinal direction of the front air bag grid 11, the protrusion protrudes substantially parallel to the second two sides 172 of the leg 17 toward the cushion layer 6 to break the cushion layer 6 and the skin 5 of the instrument panel. Is provided. This blade portion 19 is provided with the front airbag grid 1.
1 is provided to ensure the deployment, but it can also be provided in the rear airbag lid 12 as well. Here, for example, when the front air bag grid 11 is made larger than the rear air bag grid 12 and the blade portion 19 is provided on the front air bag grid 11, the front air bag grid 11
The instrument panel 1 on the side can be deployed slightly earlier than the airbag lid 12 on the rear side. By slightly providing a time lag between the deployment of the front and rear instrument panels 1 in this manner, the airbag 22 starts to inflate from the front airbag lid 11 side, and when deployed outside the room, hits the windshield first. As a result, the inflation force of the airbag 22 is reduced, and the inflation force when the airbag 22 is deployed does not directly act on the occupant in the passenger seat, so that the safety of the occupant can be further enhanced. In addition, since the instrument panel 1 substantially corresponding to the front airbag grid 11 has the blade portion 19, it is not necessary to form a visible tear line on the design surface, and the instrument panel 1 has a blade surface 19. The tear line formed on the design surface of the instrument panel 1 substantially corresponding to the above can be reduced, and the degree of freedom of the design of the instrument panel 1 can be improved.

The airbag door 2 constructed as described above
Is the instrument panel 1 as shown in FIG.
The cushion layer 6 and the skin 5 are sequentially laminated on the surface of the core material 7. The core 7 has an opening 8 for inflating the airbag, and a stepped portion 9 is formed on both sides of the instrument panel 1 in the front-rear direction of the vehicle. Each stepped portion 9 extends to the left and right sides of the instrument panel 1 along the opening 8. And, it is fixed by being fitted into the core member 7 of the instrument panel 1 by the hook part 15 provided outside the leg part 17, and the opening 8 provided in the core member 7 is closed.

As shown in FIG. 3, the airbag device 20 includes a leg 17 of the airbag door 2 and an airbag case 21 in which a passenger airbag 22 and a gas generator 23 are housed. 16 and any other fastening means.

The instrument panel 1 configured as described above has the core member 7, the skin 5, and the airbag door 2 formed respectively, and the airbag door 2 is mounted on the core member 7 in a mold (not shown). By doing, the airbag door 2
Thereby, the opening 8 of the core material 7 is closed. Subsequently, the instrument panel 1 is formed by causing the skin 5 to face the core material 7 and the airbag door 2 in the mold, and filling the gap with the cushion layer 6. At this time, since the gap is the thickness of the cushion layer 6, the gap is 1.0 to
Set to 15.0 mm.

The material of the airbag door 2 is TPO
Is used. This TPO is composed of a soft phase exhibiting entropy elasticity in the same polymer, and a hard phase which reinforces the soft phase and prevents plastic deformation. It is roughly divided into crosslinked ones.
Therefore, the physical properties of TPO are greatly affected by the melting point of the hard layer and the glass transition point of the soft phase. As the hard phase, a polyethylene resin or a polypropylene resin is used. As the soft phase, styrene-butadiene copolymer,
Ethylene propylene rubber is used. The proportion is adjusted so that the soft phase is 1 or more with respect to the hard phase 1, and the composition is appropriately adjusted depending on the application. Among them, TPO in which a polypropylene resin and an ethylene propylene rubber are blended so as to have a one-to-one composition is more preferable. Thereby, the glass transition point of TPO is set to -50 ° C to -60 ° C.
, The airbag 22 does not become brittle at low temperatures, and can be reliably deployed even when the airbag 22 is inflated,
It can sufficiently withstand practical use as an airbag door for automobiles.
The thickness of the airbag door made of TPO is 4 mm.
Even if it is the case, since the weight of the iron airbag door of the same area is about half that of the 1 mm thick one, the inertial energy generated at the time of deployment is smaller than that of the conventional metal airbag door. The airbag is easily deployed.

The material of the core 7 is polypropylene,
Resins such as acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, modified polyphenylene oxide, and styrene-maleic anhydride copolymer can be used. Preferably, TPO is used. The material of the cushion layer 6 is vinyl chloride, T
A foaming material that foams by adding a foaming agent to PO, a styrene-based thermoplastic elastomer, a urethane-based thermoplastic elastomer, a polyester-based thermoplastic elastomer, or the like can be used. The material of the skin 5 is vinyl chloride resin, vinyl chloride and acrylonitrile butadiene.
A styrene copolymer synthetic resin or TPO can be used. Then, the skin 5 is formed into a predetermined sheet shape by vacuum forming or slash forming.

As described above, by molding the core material 7, the cushion layer 6, the skin 5 and the airbag door 2 constituting the instrument panel 1 with resin, there is no need to remove only the airbag door 2 when the vehicle is scrapped. Recyclability is improved.

It is preferable that all the materials of the core 7, the airbag door 2, the cushion layer 6, and the skin 5 be TPO. By unifying the material of each member constituting the instrument panel 1, the recyclability can be further improved.

As shown in FIG. 4, the airbag door 2
In order to break the cushion layer 6 and the skin 5 in accordance with the development of the two-sided opening, a visible tear line 4 including a groove 400 is formed in the skin 5 in a square shape. The tear line 4 is formed in a wavy shape protruding toward the cushion layer 6 at a portion substantially corresponding to the peripheral portion of the rear air bag grid 12.

As shown in FIGS. 4 and 5, the tear line 4 is formed at a position facing a groove 13 formed over the entire width between the airbag grids 11 and 12 of the lid portion 10 at the front and rear of the vehicle. 400 and grooves 401 and 402 provided orthogonal to the groove 400 and parallel to the second two sides.
And a groove 40 provided in a portion facing the hinge portion 14b.
3 and is preferably formed in a substantially square shape substantially corresponding to the peripheral edge of the rear airbag grid 12. As a result, the tear line visible on the design surface can be reduced, and the design restrictions for improving the appearance can be reduced. In addition, a portion corresponding to the front airbag door 11 is, for example, on the back side of the skin 5 so that the design surface of the instrument panel 1 cannot be seen.
A tear line may be formed on the cushion layer 6 or the like.

The groove 400 has a U-shape or a U-shape having an opening in the design surface, and is formed so as to protrude deeply into the cushion layer 6 so as to be easily deployed when the airbag 22 is inflated. I have. And the three sides 40 other than the groove 400
1, 402 and 403 may be of such a degree that they can be broken and deployed by the inflation force when the airbag 22 is deployed.
It is not particularly necessary to form the groove deeply toward the cushion layer 6 as described above, and the groove 403 does not need to be particularly formed.

When the airbag 22 is inflated, the tear line 4 formed on the design surface of the instrument panel 1 serving as a starting point of the deployment is connected to the rear airbag grid 12.
Since it is formed only at the peripheral edge portion, there is no restriction on the design, and the deterioration of the appearance quality can be suppressed.

Next, the opening operation of the airbag integrated instrument panel according to the present embodiment will be described with reference to FIGS. FIG. 6 is a sectional view for explaining the operation of the airbag door structure according to the embodiment of the present invention.
FIG. 2 is a perspective view illustrating a deployed state of the instrument panel surface when deployed using the airbag door according to the embodiment of the present invention.

When the vehicle collides, the gas released from the gas generator 23 inflates the airbag 22 toward the lid 10. Then, when the lid portion 10 receives the force due to the inflation of the airbag 22, the lid portion 10 is torn along the groove portion 13, and the cushion layer 6 and the skin 5 are broken along the groove 400 with the groove 400 as a starting point of deployment. At the same time, the airbag lids 11 and 12 are
The instrument panel 1 is rotated about 90 ° by 14a and 14b to open both front and rear sides of the instrument panel 1. At this time, the blade portion 19 provided on the front airbag lid 11 causes
The cushion layer 6 and the skin 5 are pushed up, broken and unfolded along the blade portion 19. Slightly behind this, the cushion layer 6 and the skin 5 are broken and unfolded on the rear airbag grid 12 side by the inflation force of the airbag 22 along the visible tear line 4 on the instrument panel surface. In this manner, the airbag 22 is deployed in the room first from the front airbag lid 11 side, once hits the windshield, its inflation output is reduced, and the airbag 22 is inflated into the vehicle compartment from the opening 8. Therefore, the inflation output of the airbag 22 does not directly act on the passenger in the passenger seat.

[0034]

The airbag door of the present invention is constructed as described above. According to the first aspect of the present invention, it is possible to reduce the weight of the airbag door, and a large inertial energy is generated when the airbag is inflated. It does not occur and the deployment of the airbag door can be facilitated. In addition, by using TPO for the airbag door, all the components such as the instrument panel core, cushion layer, and skin can be formed of the same type of resin, which improves the recyclability. Play.

According to the second aspect of the present invention, it is possible to open both sides of the entire lid portion with the groove as a boundary, and it is not affected by the size of the outer frame of the lid portion of the airbag door as in the related art. Since the airbag door can be formed in accordance with the size of the ment panel, restrictions on design and design are reduced, and an effect that the design of the airbag door can be diversified is produced.

According to the third aspect of the present invention, the cushioning layer and the skin of the instrument panel can be reliably broken and opened by the inflation of the airbag even in a low-temperature environment.

According to the fourth aspect of the present invention, when the vehicle is scrapped, the fixing member for attaching the airbag door to the core member is not removed,
By simply removing the airbag device, the entire instrument panel can be crushed, which has the effect of improving recyclability.

According to the fifth aspect of the present invention, the airbag door can be reliably deployed when the airbag is inflated even in a low-temperature environment, and the generation of small debris and the like during deployment can be prevented. Play.

According to the sixth aspect of the present invention, since the airbag door is made of resin, the airbag door can be reduced in weight, no large inertial energy is generated when the airbag door is deployed, and the entire surface of the lid can be easily opened in both directions. It can be expanded. In addition, unlike the related art, the airbag door is not affected by the size of the outer frame of the lid portion of the airbag door, and the airbag door can be formed according to the size of the instrument panel. This has the effect of reducing design constraints.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of an airbag door according to an embodiment.

FIG. 2 is a schematic cross-sectional view taken along line AA of the airbag door in FIG.

FIG. 3 is a schematic cross-sectional view taken along the line BB in a state where the airbag door in FIG. 1 is attached to an instrument panel.

FIG. 4 is an overall perspective cross-sectional view showing a state of being attached to an instrument panel.

FIG. 5 is an overall perspective view of an instrument panel.

FIG. 6 is a cross-sectional view illustrating the operation of the airbag door structure according to the embodiment of the present invention.

FIG. 7 is a perspective view illustrating a deployed state of the instrument panel surface when deployed using the airbag door according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Instrument panel 2 Airbag door 4 Tier line 400,401,402,403 Groove 5 Skin 6 Cushion layer 7 Core material 701 First two sides 702 Second two sides 8 Opening 9 Stepped part 10 Lid part 11 Front air bag grid 12 Rear air bag grid 13 Groove 14a, 14b Hinge 15 Hook 16 Rivet 17 Leg 18 Notch 20 Airbag device 21 Airbag case 22 Airbag 23 Gas generator

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Sadao Teranishi 4-1-1-21 Hamazoedori, Nagata-ku, Kobe City, Hyogo Prefecture Inside Mitsuboshi Belting Co., Ltd. (72) Inventor Yutaka Hirako 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor (72) Inventor Koji Eguchi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3D044 BA01 BA17 BB01 BC02 BD04 3D054 AA03 AA14 BB09 BB10 BB13 BB16 BB23 BB24 BB30 FF04 FF14 FF18 FF20

Claims (6)

[Claims] 1. A lid portion attached to a core material of an instrument panel, a cushion layer and a skin are sequentially laminated on the surface thereof, and the cushion portion and the skin are broken and deployed by inflation of an airbag. A leg portion extending below the lid portion and attaching an airbag device, wherein the lid portion and the leg portion are attached to the core material as an integral body molded of an olefin-based thermoplastic elastomer. Airbag door. 2. The leg portion has a rectangular frame shape, and the lid portion has a first two sides facing each other of the square frame as a support point, and has a gap between the other two opposite sides. A plate shape integrally attached to the leg portion so as to be detachable, extending over the entire width along a line between the first two sides, and the entire lid portion being inflated by airbag inflation; 2. A groove portion is provided, which is divided into two and is developed in a double-opened shape.
The described airbag. 3. A blade part for projecting substantially parallel to the second two sides and breaking the skin and the cushion layer is provided at both ends on at least one opening side of the surface of the lid part having a double opening. 3. The airbag door according to claim 2, wherein the door is provided. 4. The airbag door according to claim 2, wherein the lid portion and the core member are attached by fitting. 5. The airbag door according to claim 1, wherein a glass transition temperature of the olefin-based thermoplastic elastomer is in a range of −50 to −60 ° C. 6. A quadrangular frame-shaped leg to which an airbag device is attached, and a pair of opposing first two sides of the quadrangular frame serving as support points, and a second opposing second side can be cut off. A plate-shaped lid portion integrally attached to the leg portion so that the lid portion is provided over the entire width along a line between the first two sides, and the lid is expanded by an airbag. A resin airbag door comprising: a groove portion that divides the entire part into two parts and expands the part in a two-sided manner.