JP2018090093A - Air bag lid for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag lid for vehicle in which a tear line can be torn in the intended order and which can secure the stable opening operation of a door part.SOLUTION: A lid part 1 includes a tear line 5 formed of a groove on a rear surface. Door parts 31, 32 open to a cabin side with the tear line 5 torn by the pressing force from an air bag at the expansion of the air bag. The tear line 5 includes: a central tear line 10; and side tear lines 21 to 24 which respectively branch into two from both ends 10x, 10y thereof and extend in the direction crossing the central tear line 10. The groove width of a central part 11 of the central tear line 10 is narrower than the groove width of another portion 12 and side tear lines 21 to 24. With mutual contact of edge portions of the groove of the central part 11 of the central tear line 10 at the expansion of the air bag, the central part 11 is torn first, the tear propagates to portions 12 on both sides of the central tear line 10, and further propagates to the side tear lines 21 to 24.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an airbag grid installed in an interior of a vehicle, and more particularly to an improvement in a tear line formed in the airbag grid.

An airbag grid is attached to a part corresponding to a passenger seat of an interior of a vehicle, for example, an instrument panel (hereinafter referred to as instrument panel).
An air bag grid for an instrument panel disclosed in Patent Document 1 includes a lid portion, a flange portion that is flush with the lid portion and arranged around the lid portion, and a rear surface of the lid portion so as to surround the lid portion. And a projecting frame portion. The collar portion is fixed to the instrument panel, and the airbag device is supported by the frame portion.

  As shown in Patent Document 1, a tear line forming a V groove is formed on the back surface of the lid portion. A typical tier line has a central tier line and a total of four side tier lines extending in two directions from both ends of the central tier line and extending in a direction crossing the central tier line. The lid portion has a plurality of door portions defined by a central tear line and four side tear lines.

  When an airbag is deployed at the time of a vehicle collision, the tear line is torn by being pushed by the airbag, and a plurality of door portions defined by the tear line are opened to the passenger compartment side to encourage the airbag to be deployed in the passenger compartment. It has become.

Japanese Patent Laid-Open No. 2008-239065

  As described above, when the airbag is deployed, it usually starts to tear in the vicinity of the center of the center tear line. However, the site where the tear begins varies irregularly depending on how the airbag is deployed. For example, it starts to tear from a portion away from the center of the central tear line, the intersection of the central tear line and the side tear line, or rarely starts to tear from the side tear line. For this reason, there is a possibility that the opening operation of the door portion is not constant, which hinders the design of optimal airbag control.

The present invention has been made to solve the above-described problems, and has a tear line formed by a groove formed on the back surface. The tear line is broken by the pressing force from the airbag when the airbag is deployed, and the tear line defines the tear line. In the vehicle airbag grid configured such that the formed door portion opens to the passenger compartment side, the width of the groove in the specific part of the tear line is narrower than the width of the groove in the other part of the tear line, and the airbag It is characterized in that both side portions of the groove at the specific portion are in contact with each other at the time of deployment.
According to the above configuration, when both sides of the groove hit each other at a specific part of the tear line, a “leverage action” with this contact point as a fulcrum causes a bottom part of the groove at the specific part to be a groove at another part. Compared with this, a large tensile force acts. For this reason, the tear line begins to tear first at a specific part of the tear line, and this tear propagates to other parts. Since the tear line tearing is determined in this way, it is possible to suppress a change in the opening operation of the door portion for each vehicle and to design an optimal airbag control.

Preferably, the tier line has a central tier line and side tier lines that extend in two directions from both ends of the central tier line and extend in a direction intersecting the central tier line, and the specific part is In the central tear line, the width of the groove in this specific part is narrower than the width of the groove in the other part of the central tear line and the side tear line.
According to the above configuration, the door portion can start to tear reliably from the central tear line without starting to tear from the side tear line, so that the door portion can perform a stable opening operation.

Preferably, the specific part is a central part of the central tear line.
According to the said structure, the opening operation | movement of a door part can be performed still more stably.

Preferably, the specific portion is formed with a pair of convex portions protruding from both side surfaces of the groove of the other portion adjacent to the specific portion, and a gap between the pair of convex portions is a width of the groove at the specific portion. Thus, the edge portions of the convex portions that are parallel to each other hit the airbag.
According to the above configuration, the “leverage action” at the specific part can be exhibited to the maximum.

  According to the present invention, the tear lines are torn in the intended order when the airbag is deployed, and changes in the opening operation of the door portion can be suppressed. Therefore, optimal airbag control can be designed with high accuracy.

It is a rear view of the airbag grid for vehicles concerning a 1st embodiment of the present invention. It is an enlarged rear view of the S section in FIG. (A) is AA arrow sectional drawing of FIG. 2, (B) is BB arrow sectional drawing of FIG. (A)-(C) are sectional drawings which show how to tear in the center part of the center tear line at the time of airbag deployment in time series.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the vehicle air bag grid is made of an injection-molded product of resin, and has a lid portion 1 that forms a long and narrow rectangle (square) in the vehicle width direction, and a flange portion 2 that is disposed around the lid portion 1. The lid portion 1 is integrally provided with a frame portion 3 that protrudes from the back surface of the lid portion 1 so as to surround the lid portion 1. The surface on the front side of the lid portion 1 and the flange portion 2 is continuous with each other.

  The airbag grid is mounted on an instrument panel (interior) of a vehicle (not shown). Briefly, a mounting hole is formed in a portion of the instrument panel that faces the passenger seat, and the flange 2 is closed to the periphery of the mounting hole so that the mounting hole is closed by the lid portion 1. Is attached. The front surface of the collar part 2 and the instrument panel core is flush with each other. The instrument panel core, the lid portion 1 and the flange portion 2 of the air grid are covered with a skin (not shown).

  An air bag device is attached to the frame portion 3. Briefly, a holding frame is connected to the frame portion 3, and the airbag is held in a state where the airbag is folded.

  A tear line 5 made of a groove is formed on the back surface of the lid portion 1. The tier line 5 has one central tier line 10 and four side tier lines 21-24.

The center tear line 10 extends linearly in the vehicle width direction of the lid 1 so as to divide the lid portion 1 into two substantially vertically.
The side tear lines 21 and 22 are split into two forks from one end 10x of the center tear line 10 at right angles to the center tear line 10 and extend linearly toward the two corners of the lid portion 1. The side tear lines 23 and 24 are divided into two forks from the other end 10y of the center tear line 10 at right angles to the center tear line 10 and extend linearly toward the other two corners of the lid portion 1. .

The lid portion 1 includes a door portion 31 surrounded by the central tier line 10 and the side tier lines 21 and 23, and a door portion 32 surrounded by the central tier line 10 and the side tier lines 22 and 24. Yes.
The portion along the long side of the rectangle of the lid portion 1 is thin, and serves as hinge portions 31 a and 32 a for the doors 31 and 32.

  In the central tear line 10, the portion 12 excluding the central portion 11 (specific portion) forms a V groove having a constant groove width Wa (see FIGS. 2 and 3). Both side surfaces 12a of the V-groove are inclined, and the bottom 12b of the V-groove is the thinnest.

  The central portion 11 of the central tear line 10 has a pair of convex portions 11 a that protrude from both side surfaces 12 a of the V groove of the portion 12. The gap W between the pair of convex portions 11 a, that is, the width Wb of the groove in the central portion 11 is narrower than the width Wa of the groove in the other portion 12. The bottom part 11 b of the central part 11 has the same thickness as the bottom part 12 b of the other part 12.

  The convex portion 11 a is flush with the back surface of the lid portion 1, and the opposing surfaces are substantially orthogonal to the back surface of the lid portion 1. The pair of convex portions 11a have edge portions 11x (both side portions of the groove) that are parallel to each other.

  The side tear lines 21 to 24 are also V-grooves having the same groove width as that of the central tear line 10. The groove widths of the side tear lines 21 to 24 may be slightly narrower or slightly wider than the central tear line 10, but are wider than the groove width Wb of the central part 11 of the central tear line 10.

  A tear line corresponding to the tear line 5 is formed on the skin covering the airbag grid and the instrument panel core.

  In the airbag grid having the above-described configuration, when the airbag is deployed and the lid portion 1 is pressed at the time of a vehicle collision, the lid portion 1 is curved so as to swell toward the passenger compartment. Therefore, the central tear line 10 and the side tear lines 21 to 24 are torn, the lid portion 1 is divided into two door portions 31 and 32, and these door portions 31 and 32 are rotated around the hinge portions 31a and 32a. Opens to the passenger compartment side and encourages the airbag to be deployed in the passenger compartment.

  In a normal airbag grid that does not have the features of the present invention, as described above, the portion that starts to tear does not become constant depending on how the airbag is deployed, and sometimes the tear tears start from the central tear line 10 or the side tear line 21. It may start to tear at ~ 24.

  In the present embodiment, tearing starts from the central portion 11 of the central tear line 10, and the tear propagates from the central portion 11 to the portions 12 on both sides and further propagates to the side tear lines 21 to 24. Hereinafter, it will be described in detail with reference to FIG.

  When the lid portion 1 is pushed with the force indicated by the arrow F1 by the deployed airbag, the lid portion 1 is curved so as to swell toward the passenger compartment. Therefore, a tensile force acts on the bottom portions 11b and 12b of the grooves of the central portion 11 and the other portions 12 of the central tear line 10 and the bottom portions of the grooves of the side tear lines 21 to 24.

  At the central portion 11 of the central tear line 10, as shown in FIG. 4A, the edge portions 11x of the pair of convex portions 11a facing each other with a narrow groove width Wb come into contact with each other as the lid portion 1 is curved. A “lever” force F2 with the portion 11x as a fulcrum is also applied to the bottom portion 11b. Therefore, the bottom part 11b of the groove of the central part 11 receives a much larger tearing force than the bottom part 12b of the groove of the other part 12 of the central tear line 10 and the bottom part of the grooves of the side tear lines 21-24. As a result, the central portion 11 of the central tear line 10 is torn first as shown in FIGS. 4 (B) and 4 (C).

As described above, since the part to start tearing and the tearing order in the tear line 5 are constant, the opening operation of the door portions 31 and 32 is also constant, and optimal airbag control can be designed with high accuracy.
In particular, in the present embodiment, the tear starts to propagate from the central portion 11 of the central tear line 10 and the tear propagates to both the left and right sides of the central tear line 10, so that the opening operation of the door portions 31 and 32 is stabilized.

The present invention is not limited to the above-described embodiment, and various aspects can be made.
Two side tear lines may be connected from both ends of the central tear line at an obtuse angle (in a Y shape). In this case, four door portions are defined by the central tear line and the four side tear lines. Others are the same as those in the first embodiment.
The center tear line and the side tear line may be curved instead of linear.
The specific part with the narrow groove width may be located away from the central tear line.
Without being restricted by the above-described embodiments, the tear line can adopt various forms.

  The present invention can be applied to an air bag grid for a vehicle.

1 Lid part 5 Tier line 10 Center tier line 11 Center part of the center tier line (specific part)
11a Convex 11b Groove bottom 11x Convex edge (both sides of the groove)
12 Other part 12a of the central tear line 12a Both side surfaces 12b of the groove Bottom 21-24 of the groove Side tear line Wa Groove width Wb of the other part Groove width of the central part

Claims (4)

It has a tear line formed by a groove formed on the back surface, and the tear line is torn by the pressing force from the airbag when the airbag is deployed, and the door part defined by the tear line opens to the passenger compartment side. In the vehicle air bag grid,
A vehicle airbag grid, wherein a width of a groove at a specific portion of the tear line is narrower than a width of a groove at another portion of the tear line, and both side portions of the groove at the specific portion hit each other when the airbag is deployed. .   The tier line has a central tier line and side tier lines that branch off from both ends of the central tier line and extend in a direction intersecting the central tier line, and the specific portion is the central tier line. 2. The vehicle airbag grid according to claim 1, wherein a width of the groove in the specific portion is narrower than a width of the groove in the other portion of the central tear line and the side tear line.   The vehicle airbag grid according to claim 2, wherein the specific portion is a central portion of the central tear line.   The specific part is formed with a pair of convex parts protruding from both side surfaces of the groove of the other part adjacent to the specific part, and the gap between the pair of convex parts becomes the width of the groove in the specific part. The vehicle airbag grid according to any one of claims 1 to 3, wherein edge portions of the convex portions that are parallel to each other hit the airbag.

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