JP4861682B2 - instrument panel - Google Patents

Description

  The present invention relates to an instrument panel having a two-layer structure in which a surface of a base material layer is covered with a surface layer and a tear line is formed on the back surface of the base material layer to be cleaved when an airbag is inflated.

  Conventionally, an airbag device that protects an occupant from an impact when a car collides is installed, for example, at the center of a steering wheel or inside an instrument panel.

  The airbag device installed inside the instrument panel includes an airbag that is inflated and deployed by a high-pressure gas ejected from an inflator when an automobile collides, and a tear line that is cleaved by the inflation pressure of the airbag is installed in the instrument. It is formed on the back surface of the ment panel.

  Most of the tear lines are formed in a substantially “day” shape on the inner surface of the instrument panel by the V-shaped groove, and when the airbag is inflated, the cover covering the upper surface of the airbag is pushed upward.

  As a result, the central horizontal linear groove portion of the tear line is first cleaved, and accordingly, the left and right vertical linear groove portions connected to both ends of the central horizontal linear groove portion are cleaved, and the airbag of the instrument panel is separated from the central horizontal linear groove portion. When the portion covering the vehicle is pushed up and down, the airbag is deployed to the occupant side to protect the occupant from the impact at the time of collision.

  On the other hand, in recent years, a seamless instrument panel has been put into practical use in which the tear line formed on the back surface of the instrument panel is not displayed on the surface of the instrument panel in order to improve the design appearance and enhance the sense of quality. .

  The seamless instrument panel has a two-layer structure in which the surface of a base material layer formed of a hard resin is covered with a surface layer made of a soft resin such as polyurethane, and a tear line is formed on the back surface of the base material layer. However, the surface layer covering the base material layer has a structure in which the tear line does not appear on the surface of the instrument panel.

  Moreover, as an airbag cover which employ | adopted such a 2 layer structure, what was described, for example in patent document 1 and 2 is well-known.

  The cover cap of the airbag described in Patent Document 1 has a center horizontal linear groove structure of a tear line, and the cover layer covering the support layer is weakened in the tear-offline region by the groove, and the support layer is the cover layer. The cover cap pushed up by the airbag surely pushes and opens along the intended line.

Further, the airbag cover body described in Patent Document 2 is an airbag cover body provided at the center of the steering wheel, and is different from the airbag provided on the inside of the instrument panel. The first curved surface portion and the second curved surface portion to be formed have a center on the back surface side, are smoothly continuous with each other, and the curvature of the first curved surface portion is larger than the curvature of the second curved surface portion. It has become.

And even if the surface of a cover body is pressed by the said structure, since a pressure is disperse | distributed along a 2nd curved surface, it has the effect by which the deterioration of the external appearance of a fracture | rupture part by stress concentrating on one part is suppressed. is doing.
Special Table 2000-512953 Japanese Patent No. 2527285

  However, the cover cap of the airbag described in Patent Document 1 relates to the central horizontal linear groove structure of the tear line, and there is no description about the left and right vertical linear groove structures that are continuous at both ends of the central horizontal linear groove.

  Further, in the cover cap described in Patent Document 1, even when the tear line of the central horizontal portion is cleaved along the intended line, the left and right vertical linear groove portions that are continuous at both ends of the central horizontal linear groove portion act on the cover layer. There is a problem that the surface layer cannot be reliably broken along the intended line because the breaking line may meander in the direction of the breaking force to be generated and the breaking line may meander.

  On the other hand, in the cover body of the airbag described in Patent Document 2, the appearance of the cover body is not impaired even when the external pressure of the cover body is applied, and is not intended to be cleaved when the airbag is inflated. Absent.

  For this reason, even if the structure of the cover body described in Patent Document 2 is applied to an instrument panel, the break line may meander and the break line may meander in the direction of the break force acting on the surface layer. There is a problem that the surface layer cannot be reliably broken along the line.

  The present invention has been made to solve such a problem, and an instrument panel having a two-layer structure that can reliably break the surface layer along the intended line of the tear line formed on the back surface of the base material layer. It is intended to provide.

The instrument panel of the present invention is an air that is housed in an upper case in a state in which a lid is fixed to the inside of an instrument panel body that includes a base material layer and a surface layer that covers the surface of the base material layer. An instrument panel comprising a bag and a tear line formed on the back surface of the base material layer so as to form a door portion that opens when the airbag is inflated, wherein the door portion in the tear line Left and right vertical linear groove portions are formed in a V-shaped groove, and the side of the left and right vertical linear groove portions facing the door portion is bulged out of the airbag. The bottom surface is substantially parallel to the direction, and the side facing the door portion of the left and right vertical linear groove is a bottom surface inclined in a direction lying on the side of the airbag inflating direction. The base material layer is formed below the intersection of the extension line of the bottom surface and the extension line of the inner surface of the upper case that is formed so as to lie on the side of the airbag inflating direction. By forming a protrusion on the surface, a thin-walled portion is formed on the extended line on the bottom surface of the surface layer that is inclined in a direction lying on the bulging direction of the airbag , In addition, the cross-sectional shape of the ridge is substantially parallel to the bulging direction of the airbag by the curved line having a small curvature on the extended line side of the side bottom surface inclined so as to lie on the bulging direction of the airbag The bottom surface is formed by a gentle curve with a large curvature.

  With the above-described configuration, the shearing force is concentrated upward along the extended line of the bottom surface of the V-shaped groove forming the door partition linear groove portion, which is inclined in a direction lying on the airbag inflating direction. Since this shear force acts directly on the surface layer, the surface layer can be reliably broken along the intended line.

  In addition, when the door partition linear groove is cleaved by the shearing force generated along the bottom surface inclined in the direction lying on the side of the airbag inflating direction, a tensile force is generated in the vertical direction in the base material layer. By forming the bottom surface so that it is almost parallel to the direction of the airbag's bulging, it is possible to suppress the stretching of the base material layer due to the tensile force, so that the shearing force can be effectively used for the door partition linear groove portion of the tear line. It can be added to the surface layer, whereby the door section linear groove portion and the surface layer of the tear line can be broken in a stable state.

Further, according to the above configuration, the shear force generated intensively along the extension line of the bottom surface inclined in the direction lying on the side of the airbag inflating direction acts directly on the thin portion of the surface layer, and the direction Therefore, the surface layer can be reliably broken without meandering from the thin wall portion.

Furthermore, the above configuration makes it easier to break the thin wall portion formed by a curve with a small curvature, and the breakage proceeds along the thin wall portion, thus reliably preventing the break line of the surface layer from meandering. can do.

  According to the instrument panel of the present invention, the shearing force along the extension line of the bottom surface of the V-shaped groove forming the door partition linear groove portion is inclined in a direction lying on the bulging direction of the airbag. Since the shearing force acts directly on the surface layer, the surface layer can be reliably broken along the intended line, and the air bag bulges in the direction of inflation. When the door partition linear groove is cleaved by the shearing force generated along the bottom surface inclined in the recumbent direction, a tensile force is generated in the vertical direction in the base material layer, but it is almost parallel to the airbag inflating direction. By forming the bottom surface as described above, it is possible to suppress the elongation of the base material layer due to the tensile force, so that the shear force can be more effectively applied to the door partition linear groove portion and the surface layer of the tear line. By stable It is possible to break the door compartment linear grooves and the surface layer of the tear line in the state.

  Embodiments of the present invention will be described in detail with reference to the drawings.

  1 is a plan view of an instrument panel in which an airbag device is installed inside, FIG. 2 is an exploded perspective view thereof, FIG. 3 is a sectional view taken along line AA in FIG. 1, and FIG. FIG. 5 is a sectional view taken along line B and FIG.

  The instrument panel body 1 shown in FIG. 1 and FIG. 2 is installed at the front part of the passenger compartment, and the base layer 2 formed by injection molding a hard resin, and the surface of the base layer 2 The surface layer 3 is composed of a surface layer 3 to be covered, and the surface layer 3 is formed of a soft resin such as polyurethane.

  Inside the instrument panel body 1, an airbag device 4 is installed in front of a passenger seat (not shown).

  As shown in FIG. 3, the airbag device 4 includes a rectangular box-shaped upper case 4a formed of resin, and a lower case 4b made of metal attached to the bottom of the upper case 4a. An inflator 5 that ejects high-pressure gas when an automobile collides is accommodated in 4b.

  In the upper case 4a, the airbag 6 is accommodated in a folded state, the gas inlet of the airbag 6 is connected to a gas outlet (none of which is shown) of the inflator 5, and the upper case 4a The upper surface opening of the case 4a is closed by a lid body 4c, and a thin-walled portion 4d that is torn when the airbag 6 is inflated is formed in a horizontal direction at a substantially central portion in the front-rear direction of the lid body 4c.

  The front and rear edges of the lid 4c are connected to the opening edge of the upper case 4a via a hinge 4e formed by thinning part of the lid 4c, and the airbag 6 is inflated. The lid 4c is opened upward around each hinge 4e.

  And the upper surface of the flange 4f protruding from the opening edge of the upper case 4a and the lattice-like protrusion 4g formed on the upper surface of the lid 4c are formed on the back surface of the base material layer 2 constituting the instrument panel main body 1. It is fixed by adhesive means such as vibration welding.

  On the other hand, a tear line 2a is formed on the back surface of the base material layer 2 to which the upper surface of the flange 4f of the upper case 4a and the upper surface of the lid 4c are fixed.

  The tear line 2a includes upper and lower horizontal linear groove portions 2b and 2c, left and right vertical linear groove portions 2d and 2e that vertically connect both ends of the horizontal linear groove portions 2b and 2c, and a substantially intermediate portion between the left and right vertical linear groove portions 2d and 2e. The central horizontal linear groove 2f formed by the V-shaped groove is a thin portion formed at the substantially central portion of the lid 4c. It is located above 4d.

  The upper and lower horizontal linear groove portions 2b and 2c and the left and right vertical linear groove portions 2d and 2e are substantially located on the vertical extension line 2g of the inner surface of the upper case 4a, and the upper and lower horizontal linear groove portions 2b and 2c are formed by V-shaped grooves. However, the left and right vertical linear groove portions 2d and 2e are formed by V-shaped grooves whose bottom surfaces 2i and 2j are asymmetric with respect to the extension line 2g as shown in FIG. 4, and the airbag 6 is inflated. A door section linear groove section is formed to partition and form the outer line of the door section 2x that opens.

  Of the bottom surfaces 2i and 2j forming the asymmetric V-shaped groove, the bottom surface 2i on the side to which the flange 4f is fixed is substantially parallel to the extension line 2g of the inner surface of the upper case 4a, that is, the airbag inflating direction. The bottom surface 2j that is formed vertically and to which the lid 4c is fixed, that is, the bottom surface 2j on the airbag 6 side is inclined in a direction lying on the extension line 2g by an angle θ, and the bottom surface 2j is inclined by an angle θ. Below the intersection 2n of the line 2k and the extension line 2g of the inner surface of the upper case 4a, a protrusion 2p is provided on the upper surface of the base material layer 2.

  The protrusion 2p has substantially the same length as the left and right vertical linear groove portions 2d and 2e, and is formed by a curved line having a small curvature on the extension line 2k side and a gentle curve on the opposite side, that is, the extending line 2g side. It has a cross-sectional shape, and a thin portion 3a having a thickness t is formed on the surface layer 3 covered with the surface of the base material layer 2 by these protrusions 2p.

  Next, the operation of the instrument panel having the above-described configuration will be described.

  The instrument panel main body 1 is attached to the front part of the passenger compartment, and the airbag device 4 assembled inside the instrument panel main body 1 is in front of an occupant seated in the passenger seat (none of which is shown). Is located.

  When the automobile collides in this state, the folded airbag 6 starts to be inflated by the high-pressure gas ejected from the inflator 5, and pushes up the lid 4c that closes the upper surface opening of the upper case 4a.

  As a result, the thin portion 4d of the lid 4c is broken, and the lid 4c starts to rotate upward about the hinge 4e. Therefore, the lid 4c is formed on the back surface of the base material layer 2 by the pushing force F of the lid 4c. The central horizontal linear groove portion 2f of the tear line 2a is cleaved by a tensile force, and at the same time, the thin portion of the surface layer 2 due to the protrusions formed on the upper surface of the base material layer 2 along the central horizontal linear groove portion 2f (both not shown) ) Is broken.

  When the airbag 6 is further inflated, the base material layer of the portion surrounded by a frame shape by the vertical horizontal linear groove portions 2b and 2c and the left and right vertical linear groove portions 2d and 2e as shown in FIG. 2 is pushed up, so that shear force is generated along the extension line 2k of the bottom surface 2j on the side inclined in the direction lying on the side of the angle θ among the bottom surfaces 2i and 2j of the V-shaped grooves forming the left and right vertical linear groove portions 2d and 2e. F1 is intensively generated upward as shown in FIG.

  Since the thin portion 3a is formed in the surface layer 3 by the protrusion 2p on the extension line 2k of the bottom surface 2j, the shearing force F1 generated intensively along the extension line 2k of the bottom surface 2j is in the direction. It acts directly on the thin portion 3a without causing variation, and as a result, the thin portion 3a of the surface layer 3 is reliably broken along the intended line.

  When the tear line 2a of the base material layer 2 and the thin portion 3a of the surface layer 3 are cleaved, the surface layer 3 is opened upward around the hinge 4e together with the lid 4c. It will be deployed to the passenger side of the car to protect the passenger from the impact at the time of impact.

  Further, when the left and right vertical linear grooves 2d and 2e of the tear line 2a are cleaved by the shearing force F1 generated along the bottom surface 2j inclined in the direction lying on the side of the angle θ, the base material layer 2 to which the flange 4f is fixed is As shown in FIG. 5, a tensile force F2 is generated in the vertical direction, but the bottom surface 2i on the flange 4f side is formed in advance so as to be substantially parallel to the inner surface of the case 4a, and the upper case 4a supports the tensile force F2. Therefore, the extension of the base material layer 2 by the tensile force F2 generated in the base material layer 2 can be suppressed, whereby the shear force F1 can be more effectively used as the left and right vertical linear grooves 2d and 2e of the tear line 4a and It can be added to the thin portion 3 a of the surface layer 3.

  Furthermore, the cross-sectional shape of the protrusion 2p projecting from the surface of the base material layer 2 so as to form the thin portion 3a on the surface layer 3 has a gentle curve on the extension line 2k side and a large curvature on the extension line 2k side. Since the thin-walled portion 3a formed by the curved line having a small curvature is more easily broken, and the breakage proceeds along the thin-walled portion 3a formed by the curved line having a small curvature. It is possible to reliably prevent the rupture line from meandering.

  The top of the V-shaped groove forming the tear line 2a may be an acute angle or an R shape.

  In the above-described embodiment, the tear line 2a includes the upper and lower horizontal linear groove portions 2b and 2c, the left and right vertical linear groove portions 2d and 2e that vertically connect both ends of the horizontal linear groove portions 2b and 2c, and the left and right vertical lines. However, the present invention is not limited to this. For example, the reverse U shape is formed. It may be formed in a groove portion having a letter shape. In this case, the entire groove portion constitutes a door partition linear groove portion, and the door portion 2x is easily opened on a line connecting both ends of the groove portion. It is conceivable to form a groove-like hinge.

  In the instrument panel of the present invention, the shear force is upward along the extension line of the bottom surface of the V-shaped groove forming the door partition linear groove portion, which is inclined in a direction lying on the side of the airbag inflating direction. Since this shear force acts directly on the surface layer, the surface layer can be surely broken along the intended line, and lying on the side of the airbag inflating direction. When the door section linear groove is cleaved by the shearing force generated along the bottom surface inclined in the direction, a tensile force is generated in the vertical direction in the base material layer, but it is almost parallel to the airbag inflating direction. By forming the bottom surface, it is possible to suppress the extension of the base material layer due to the tensile force, so that the shearing force can be more effectively applied to the door partition linear groove portion and the surface layer of the tear line, thereby stabilizing. State The tear line door partition linear groove and the surface layer can be broken, and the surface of the base material layer is covered with the surface layer, and the tear line is opened when the airbag is inflated on the back surface of the base material layer. It is most suitable for the two-layered instrument panel formed.

It is a perspective view of the instrument panel which becomes embodiment of this invention. It is a disassembled perspective view of the instrument panel which becomes embodiment of this invention. It is sectional drawing which follows the AA line of FIG. It is sectional drawing which follows the BB line of FIG. It is operation | movement explanatory drawing of the instrument panel which becomes embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Instrument panel main body 2 Base material layer 2a Tear line 2d Left vertical linear groove part (door division linear groove part)
2e Right vertical linear groove (door partition linear groove)
2f Central horizontal linear groove 2i Bottom 2j Bottom 2k Extension line 2p Projection 2x Door
3 Surface layer 3a Thin portion 6 Airbag F1 Shearing force F2 Tensile force (airbag inflation direction)

Claims (1)

An airbag housed in an upper case with a lid fixed is installed inside an instrument panel body composed of a base material layer and a surface layer covering the surface of the base material layer, and the base An instrument panel formed by forming a tear line on the back surface of the material layer so as to form a door portion that opens when the airbag is inflated, and defines a contour line of the door portion in the tear line. The left and right vertical linear groove portions of the partitioning linear groove portions are formed as V-shaped grooves, and the side facing the door portion side of the left and right vertical linear groove portions is a bottom surface substantially parallel to the inflation direction of the airbag. And the side facing the door portion in the left and right vertical linear groove portion is formed to be a bottom surface that is inclined in a direction lying on the bulging direction of the airbag, and Airba By projecting a ridge on the surface of the base material layer below the intersection of the extension line of the bottom surface and the extension line of the inner surface of the upper case that is inclined so as to lie on the bulge direction A thin-walled portion is formed on the extended line on the bottom surface of the surface layer that is inclined in a direction lying on the bulging direction of the airbag, and the cross-sectional shape of the protrusion is The extended line side of the side bottom surface that inclines so as to lie on the bulging direction of the airbag is a curved line having a small curvature, and the bottom surface side substantially parallel to the bulging direction of the airbag is a curved line having a large curvature. Instrument panel characterized by forming.

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