JP2002120684A - Air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag device, formed in small size, which can smoothly extend a total effective part of a bag main unit. SOLUTION: An external peripheral part 3a of a bag main unit 3 of this air bag device 1 is folded so as to be along a side wall 5a of a cover 5. The central part of a front panel 7 of the bag main unit 3 is extended preceding in the beginning of expansion, but the external peripheral part 3a is pressed to the side wall 5a of the cover 5 by gas, to stay in the cover 5. As the bag main unit 3 is extended in a flat condition, even the external peripheral part 3a is drawn out to the central part of the bag main unit 3 and extended while expanded. By positioning the external peripheral part 3a, increasing a thickness when it is folded, almost at a right angle relating to the other folding part, the thickness when folded can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device which is deployed when a vehicle collides to protect an occupant.
In particular, the present invention relates to an airbag device in which a bag body is folded so that it can be more stably deployed.

[0002]

2. Description of the Related Art FIG. 8 is a side sectional view showing an example of folding a bag body in a conventional general driver airbag device. A bag body 83 of a general driver airbag device 81 has a peripheral portion of a front panel 87 (shown by a solid line in FIG. 8) and a rear panel 89 (shown by a broken line in FIG. 8) having substantially the same outer shape of a circle or a square. Are sewn together. At a substantially center of the rear panel 89, a gas blowing port (hole) is provided. Normally, the sewn bag body 83 is turned over so that the seam allowance on the outer periphery is on the inside. The bag body 83 is folded into a predetermined shape and is housed in a cover (casing) 85. The cover 85 and the inflator 91 are fixed to the retainer 97. The gas inlet of the rear panel 89 is a retainer 97
Is fixed with a ring 101. At the gas inlet, the inside of the bag body 83 communicates with the gas outlet 103 of the inflator 91.

[0003] The bag body 83 of this example is first folded from two diagonal points on the outer periphery to the center with the front panel 87 inside, and folded in a roll shape. It becomes a planar shape. Further, as shown in FIG. 8, left and right end portions 83a in a rectangular longitudinal direction.
From the (outer peripheral portion of the bag body) to the center, it is rolled and folded with the front panel 87 inside. In the folded state, the outer peripheral portion 83a of the bag body 83 is located near the center of the left and right storage spaces in the cover 85, as shown in FIG.

FIG. 9 is a side sectional view showing another example of folding the conventional bag body. Bag body 113 of this example
Also, the front panel 117 and the rear panel 119 are sewn together. The bag body 113 is also folded into a flat rectangular shape like the bag body of FIG. And it is folded in a bellows shape by a fixed length from the left and right ends of the rectangular shape. Further, the portion folded in a bellows shape is made into one lump, and is rolled and folded with the front panel 117 inside. Also in this example, as shown in FIG.
3a and 113b (the outer peripheral portion of the bag body) are located near the center of the left and right storage spaces in the cover.

[0005]

When the above-described airbag apparatus is operated, the bag body is deployed from the vicinity of the center of the front panel in contact with the opening of the inflator at the initial stage of inflation. Above the front panel, as described above, the portion including the outer peripheral portion of the bag body and folded in a roll or bellows shape is located. When gas is further supplied in this state, the outer peripheral portion of the bag body jumps out of the cover so as to be pushed up by the unfolding front panel. At this time, the outer peripheral portion may jump out of the cover with insufficient gas reaching.

Further, in the above-mentioned folding method, the bag body is frequently laid flat in the main deployment direction of the bag body (toward the occupant), so that the thickness of the bag body is increased. In particular, the outer periphery of the bag body is usually formed so that the seam allowance is on the inside, and the bag body is overlapped in the developing direction of the bag body. Therefore, the number of stacked panels at this portion is four, and the thickness is increased. Therefore, the cover for accommodating the bag body also increases in thickness, and the entire airbag device becomes thicker.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an airbag device which is small in size and can smoothly deploy all effective portions of a bag body. .

[0008]

In order to solve the above-mentioned problems, an airbag device according to the present invention includes a bag body that inflates and deploys in front of an occupant in an emergency, and the bag body is stored in a folded state. And a casing, wherein an outer peripheral portion of the bag body is folded along a side wall of the casing.

In the initial stage of inflation, the central portion of the front panel of the bag body is deployed first. During this time, the outer peripheral portion of the bag main body is pressed against the side wall of the cover (casing) by the supplied gas and cannot protrude from the cover. Then, as the bag body expands into a flat state, the outer peripheral portion of the bag body is pulled out to the central portion of the bag body and expands while expanding. As described above, when the airbag is deployed, the gas is filled from the central portion of the bag body near the inflator, but the outer peripheral portion of the bag body that is not sufficiently filled with the gas remains in the cover. Then, only the gas-filled portion serving as the shock absorbing portion is deployed from the inside of the cover, and finally deployed with the entire bag filled with the gas. Therefore, the whole bag can be deployed stably and smoothly.

Further, the outer peripheral portion, which increases in thickness when folded, is positioned substantially at right angles to the other folded portions, so that when folded, the main body of the bag body in the main deployment direction (direction toward the occupant). The thickness can be reduced, and the entire airbag device can be downsized.

The side wall of the casing in the present invention includes the side wall of the cover, the side wall of the retainer, the side wall of the bag container (inner), and the like. Further, the side wall is a wall substantially parallel to the main deployment direction of the bag body (direction toward the occupant). Further, the outer peripheral portion of the bag body also includes the vicinity of the outer peripheral portion.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing the structure of the airbag device according to the first embodiment of the present invention. In the following figures, a solid line indicates a front panel, and a broken line indicates a rear panel. The bag body 3 of the airbag device 1 is folded into a predetermined shape described later and accommodated in a cover (casing) 5. The bag body 3 is formed by joining a front panel 7 and a rear panel 9 having a substantially circular plane shape to each other at a peripheral edge thereof. A gas inlet 13 communicating with the inflator 11 is provided substantially at the center of the rear panel 9. The bag body 3 is usually used by being turned over from the gas blowing port 13 from the inside so that the seam allowance 15 at the peripheral edge protrudes into the bag body 3. Therefore, four panels are stacked on the periphery of the bag body 3. Cover 5 and flange 19 of inflator 11
Is fixed to the retainer 17. Gas inlet 13 of rear panel 9 is fixed to retainer 17 by flange 19 of inflator 11 and ring 21. At the gas inlet 13, the inside of the bag body 3 communicates with the gas outlet 21 of the inflator 11.

The bag body 3 is folded in the following procedure. FIG. 2 is a diagram schematically illustrating a folded example of a bag body of the airbag device of FIG. 1, wherein (A), (B),
(C) is a plan view, and (C ′) and (D ′) are side sectional views. 2 (C ') and (D'), illustration of the already folded and overlapped portions in FIG. 2 (B) is omitted. The bag body 3 is, as shown in FIG.
Consisting of a substantially circular front panel 7 and rear panel 9,
A gas inlet 13 is provided substantially at the center of the rear panel 9.

As shown in FIG. 2B, the bag body 3 is folded in a bellows shape from two diagonal points on the outer periphery to the center. In this example, the bag body is folded three times, and the plane shape of the bag body becomes a flat and substantially rectangular shape. The left and right end portions in the longitudinal direction at this time are hereinafter referred to as outer peripheral portions 3a and 3b. Next, FIG.
As shown in (C), the outer peripheral portions 3a and 3b at both ends are folded back by a predetermined length to the back side. In this state, the side cross section of the bag body 3 is, as shown in FIG.
Is outside, and the rear panel 9 is inside.

Then, as shown in FIG. 2 (D '), the sheet is folded in a roll shape from both ends to the center with the front panel 7 on the upper surface inside, with the folded end as the center.
Then, the outer peripheral portions 3a, 3 at the left and right ends shown in FIG.
b is left outside without being caught in the part folded in the roll shape. The bag body 3 folded in this way is
As shown in FIG. 1, it is fixed to a retainer 17 in the cover 5.

3 (A) to 3 (E) are side sectional views showing the form of the airbag device of FIG. 1 when deployed in a time series.
The bag body 3 folded as shown in FIG.
Are housed in the cover 5 as shown in FIG. At this time, the outer peripheral portion 3 a of the bag body 3 is located along the side wall 5 a of the cover 5. The gas blown out from the gas outlet 23 of the inflator 11 is supplied to the space between the lowermost front panel 7 and the rear panel 9 in the folded portion, as shown in FIG. Then, it pushes up the vicinity of the center of the front panel 7 and flows into the space between the surrounding front panel 7 and rear panel 9. At this time, due to the pressure of the gas, pressure is applied to the upper portion 5b of the cover in the upward and outward directions, and pressure is applied to the cover side wall 5a in the outward direction. Due to the pressure on the side wall 5a, the vicinity of the outer peripheral portion 3a of the bag body 3 is sandwiched between the side wall 5a and the rear panel 9 which is about to expand outward.

When the gas is further supplied, as shown in FIG. 3B, the upper cover portion 5b is cleaved to open upward and outward, and a part of the bag body 3 is exposed. Then, while the central portion of the front panel 7 is further pushed up, the gas further flows into the space between the front panel 7 and the rear panel 9 in the peripheral portion, and the portion folded in a roll shape tends to open outward. Then, as shown in FIG. 3 (C), the front panel 7 expands flat,
The part folded in a roll shape tends to open further.
However, in this state, gas has not yet reached near the outer peripheral portion 3 a of the bag body 3, and is pressed by the rear panel 9 against the side wall 5 b of the cover and held in the cover 5. At this time, the upper part 5a of the cover 5 opens more outward.

As shown in FIG. 3 (D), when the roll-folded portion is completely opened, the continuously supplied gas flows into the front portion 3a of the bag body 3 near the outer peripheral portion 3a along the side wall. It also flows into the space between panel 7 and rear panel 9. At the same time, the rear panel 9 is pulled out along the side wall 5a by the unfolding front panel 7. And
As shown in FIG. 2 (E), the rear panel 9 is further pulled out while being deployed by the flow of gas, and finally the airbag is completely deployed.

As described above, the bag body 3 is deployed while filling the outer peripheral portion 3a with the gas. Therefore, there is no possibility that the bag body 3 is unfolded without partially filling the gas. Further, the outer peripheral portion 3a of the bag body 3 has a four-sheet structure in which the seam allowances 15 overlap as described above. Since this portion is not included in the portion to be folded into a roll but is positioned outside, the thickness of the folded portion in the occupant direction can be reduced. For this reason, the whole airbag device can be made thin.

FIG. 4 is a side sectional view showing the structure of an airbag device according to another embodiment of the present invention. The bag body of the airbag device of this example has the same structure as the bag body of the airbag device of FIG.

The bag body is first folded into a flat, substantially rectangular planar shape, similar to the bag body of FIG. Then, it is folded in a bellows shape by a predetermined length from the center of the rectangle toward both ends and stacked on the front panel 7. Further, the remaining portion is folded along the upper surface of the stacked portion and the side surface of the cover 5 on the side wall 5a side. By folding in this way, the outer peripheral portion 3a is located along the side wall 5a of the cover 5.

The airbag body folded as described above is deployed as follows. When the front panel 7 is pushed up by the gas blown out from the gas outlet 21 of the inflator 11, the gas also flows into the space between the surrounding front panel 7 and the rear panel 9, and the portion that has been folded in a bellows shape is opened. I do. Then, the front panel 7 is unfolded flat, and the portion folded in a bellows shape is completely opened. However, at this time, since the outer peripheral portion 3a is sandwiched between the side wall 5a of the cover 5 and the rear panel 9 which is about to expand outward, the outer peripheral portion 3a remains in the cover 5. Further, when gas flows into the vicinity of the outer peripheral portion 3a along with the development of the front panel 7, the gas is pulled out along the side wall 5a by the front panel 7, and finally completely deployed. In FIG. 4 as well, since the bag body 3 is deployed while filling the gas to the outer peripheral portion 3a, the bag body 3 does not deploy without partially filling the gas.
Unfolds smoothly.

FIG. 5 is a side sectional view showing the structure of an airbag device according to another embodiment of the present invention. The vicinity of the center of the bag body of the airbag device of this example is shown in FIGS.
, But the outer peripheral portion 3a is
At around 7, it is folded further inward. Therefore, the end of the outer peripheral portion 3a is not directly along the side wall 5a, but the portion near the end is along the side wall 5a. Even in such a folding manner, the outer peripheral portion 3a is initially covered with the cover 5
It stays inside and unfolds ahead with the front panel center being flat. It should be noted that by folding as described above, similar effects at the time of folding and deployment can be obtained regardless of the outer diameter of the airbag.

FIGS. 6A to 6D are diagrams schematically showing an example of folding a bag body of an airbag device according to another embodiment of the present invention. Note that this example is an example of only a process until the bag body is folded into a flat rectangular shape. As shown in FIG. 6 (A), the substantially circular bag body 33 has outer peripheries 33A, 33B, 33C,
33D is folded inward to form a substantially square planar shape (primary folding). At this time, as shown in FIG. 6B, not only the seam allowance 45 but also a part of the effective portion of the front panel 37 and the rear panel 39 is folded inward in the AA cross section of FIG. ing.

Next, as shown in FIG. 6 (C), the two vertices P and Q on the diagonal of the square are folded in a bellows shape from the center to the center, and the planar shape is flat as shown in FIG. 6 (D). Shape (secondary fold). At this time, the left and right ends after the secondary folding become the above-described outer peripheral portions 33a and 33b, and are accommodated along the side wall of the cover. By folding the bag body 33 in this manner, the length of the portion where the seam allowance 45 of the outer peripheral portions 33a and 33b is folded inward is increased, and the unevenness of the thickness when the bag body 33 is folded is reduced. For this reason, the bag main body 33 can be efficiently accommodated.

FIG. 7 is a side sectional view showing the structure of an airbag device according to another embodiment of the present invention. FIG.
The airbag device 51 of FIG.
7a extends in the cover direction, and the upper end of the retainer side wall 67a is mounted inside the cover side wall 55a. The outer periphery 3a of the bag body 3 has a retainer side wall 67a.
It is housed so as to be located along. The airbag device 71 shown in FIG. 7B is of an inner cover type, and the folded bag body 3 is covered with an inner cover 72 and housed in a cover 55. The outer peripheral portion 3 a of the bag body 3 is located along the side wall 72 a of the inner cover 72.

In the airbag apparatus as shown in FIG. 7, the side wall 67a of the retainer and the side wall 72a of the inner cover are substantially parallel to the main deployment direction of the bag body 3 (direction toward the occupant). Thus, the outer peripheral portion 3a of the bag body 3 is
By locating along the side wall parallel to the main development direction of the bag main body 3, the outer peripheral portion 3a stays in the cover 55 at the beginning of the development, and the front panel central portion is developed in advance in a flat state. At the end it will be fully deployed.

[0028]

As is apparent from the above description, according to the present invention, it is possible to provide an airbag apparatus which is small and can deploy all the effective portions of the bag body more smoothly.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a structure of an airbag device according to a first embodiment of the present invention.

FIGS. 2A and 2B are diagrams schematically showing an example of folding a bag body of the airbag device of FIG. 1, wherein FIGS. 2A, 2B, and 2C are plan views, and FIGS. It is a side sectional view.

FIG. 3 is a side cross-sectional view showing a form of the airbag device of FIG. 1 in a deployed state in a time series.

FIG. 4 is a side sectional view showing a structure of an airbag device according to another embodiment of the present invention.

FIG. 5 is a side sectional view showing a structure of an airbag device according to another embodiment of the present invention.

FIG. 6 is a diagram schematically illustrating a folding example of a bag body of an airbag device according to another embodiment of the present invention.

FIG. 7 is a side sectional view showing a structure of an airbag device according to another embodiment of the present invention.

FIG. 8 is a side sectional view showing an example of folding a conventional bag body.

FIG. 9 is a side sectional view showing another folding example of the conventional bag body.

[Explanation of symbols]

1, 51, 71, 81 Airbag device 3, 33 Bag body 5, 55 Cover 7, 37 Front panel 9, 39 Rear panel 11 Inflator 13 Gas inlet 15, 45 Seam allowance 17, 67 Retainer 19 Flange 21 Ring 23 Gas outlet 72 Inner cover

Claims (1)

[Claims] 1. An airbag device comprising: a bag main body that inflates and deploys to the front of an occupant in an emergency; and a casing that stores the bag main body in a folded state. An airbag device, wherein the airbag device is folded along a side wall of the casing.