JP2003063343A - Air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag facilitating the cutting and jointing work of the base cloth forming an air bag body. SOLUTION: The air bag has an air bag body 1 having an expansion chamber 1a, 1b, and a gas introducing part 1d provided in the air bag body 1 and having a gas introducing part 1d for introducing the high pressure gas ejected from an inflator 4 into the expansion chambers 1a, 1b, the gas introducing part 1d of a double layer structure consisting of an outer part 1h and an inner part 1i by extending a cylindrical extending part 2c from the air bag body 1, and folding the top end of the extending part 2c inside is formed, and the gas introducing part 1d of the double layer structure consisting the outer part 1h and the inner part 1i so that cutting and jointing of the base cloth can be substantially reduced so as to improve the workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag that protects an occupant from a side impact.

[0002]

2. Description of the Related Art Conventionally, an airbag device for protecting an occupant from a shock generated when a vehicle collides with a vehicle is provided by inflating an airbag between a side door of the vehicle and an occupant when the vehicle has a side collision. There is a side impact airbag device that protects an occupant from the impact of a side collision.

In this side collision airbag device, an airbag body is stored in an elongated folded state inside a door frame composed of a front pillar portion, a roof side portion, a center pillar portion, a rear pillar portion and the like. The airbag body is covered with a garnish or the like so as not to be exposed inside.

When the sensor senses an impact generated when the vehicle collides sideways, high-pressure gas is ejected from the inflator, and the high-pressure gas causes the airbag body to cover the inside of the opening provided in the door frame. It is inflated and expanded in a curtain shape to protect the occupant from the impact at the time of a side collision, and as this kind of side impact airbag, for example, the one described in JP-A-2000-127886. Are known.

In the airbag of the above-mentioned publication, a gas passage for supplying gas to vacant chambers arranged in front of and behind the airbag is formed by a cylindrical body which is separate from a seat constituting the airbag,
Moreover, by opening at least one opening in this gas passage, by selecting the length of the cylindrical body that constitutes the gas passage and the position of the opening, the required space can be changed from the required position to the required space. It is designed to allow gas to flow in.

[0006]

However, like the airbag of the above-mentioned publication, the airbag and the gas passage are formed of different base fabrics (sheets), and when the airbag is sewn, the gas passage is formed into the base of the airbag. In the case of sewing into the cloth, it takes time to cut the airbag base cloth and the gas passage base cloth separately and to sew the gas passage base cloth into the airbag base cloth. There are problems such as the bag becoming expensive.

The present invention has been made to solve the above-mentioned conventional problems, and improves workability by providing an air bag which facilitates cutting and joining work of the base fabric constituting the air bag body. The purpose is to reduce the cost.

[0008]

In order to achieve the above object, the airbag of the present invention comprises an airbag body having an inflation chamber, and a high pressure gas provided in the airbag body and ejected from an inflator to the inflation chamber. An airbag having a gas introducing portion to be introduced, wherein a tubular extending portion is extended from the airbag body, and a tip end side of the extending portion is folded inward, so that the outer portion and the inner portion are separated from each other. The multi-layered gas introduction part is formed.

With the above structure, a gas introducing portion having a multi-layer structure consisting of an outer portion and an inner portion can be obtained by simply folding the distal end side of the extending portion inward, so that a base member separate from the conventional airbag body is obtained. Compared to the fabric that sewed into the airbag body fabric to form the gas passages, the work of cutting and sewing the fabric can be greatly reduced, which improves workability. At the same time, the cost of the airbag device can be reduced.

Further, since the gas introducing portion has a multi-layer structure of the outer portion and the inner portion, the mechanical and thermal strength of the high temperature and high pressure gas ejected from the inflator is improved, so that the airbag main body is improved. Since a low denier base cloth can be used for the air bag body, the air bag body can be folded compactly, and the air bag device can be downsized.

In order to achieve the above-mentioned object, the airbag of the present invention is provided with a notch on the end side of the folding line for folding the extending portion inward so as not to reach the inside than the joining means for joining both side edges of the extending portion. It was formed.

With the above construction, the tip end side of the extending portion can be easily folded inward from the folding line, so that workability is improved.

In order to achieve the above object, in the airbag of the present invention, a notch is formed on the end side of the folding line for folding the extending portion inward so as to traverse the joining means for joining both side edges of the extending portion. It is a thing.

With the above construction, the tip end side of the extended portion can be easily folded inward from the folding line, so that workability is improved.

In order to achieve the above object, the airbag of the present invention has an expanding portion having a larger cross-sectional area formed at the tip of the inner portion, and the expanding portion is located near the gas inlet of the inflating portion. The inner part is provided.

With the above structure, even in an airbag having a plurality of inflation chambers in front of and behind the airbag body, such as a curtain type airbag, the expanding portion balances the flow rates of gas flowing into the front and rear inflation chambers. Therefore, it is possible to solve the problem that the expansion amount of the front expansion chamber far from the inflator is insufficient.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a curtain type airbag for side impact will be described in detail with reference to the drawings.

FIG. 1 is a plan view of an airbag body, FIG. 2 is a perspective view of a base cloth panel constituting the airbag body, FIG. 3 is a perspective view of a gas introducing portion, FIG. 4 is the same plan view, and FIG. 4 A-A
FIG. 6 is a cross-sectional view taken along the line, and FIG. 6 is a cross-sectional view showing a state in which an inflator is attached to the gas introducing portion.

The airbag body 1 has a structure in which two peripheral cloth panels 2 having substantially the same shape shown in FIG. And has expansion chambers 1a, 1b at the front and rear,
The front and rear expansion chambers 1a and 1b are connected to each other by a connecting portion 1c.

Further, on the upper rear end side of the airbag body 1,
A gas introducing portion 1d extending obliquely upward is projected, and a gas ejection port 4a of an inflator 4 described later can be connected to the gas introducing portion 1d.

At the upper edge of the airbag body 1, for example, 3
Mounting pieces 1e are projected at, for example, five places on the rear end edge, and these mounting pieces 1e are attached to the roof side portion above the side door by a fastener (not shown) such as a screw. The airbag body 1 is attached to the inside of the roof side portion, and the front end edge of the airbag body 1 is attached to a front pillar (not shown) or the like by a tension strap.
A mounting piece 1f for fixing the front end portion of the is projected.

Base cloth panel 2 constituting the airbag body 1
Among them, the base cloth panel 2a on the outer side (side door side) is formed in a substantially rectangular shape as shown in FIG. 2, and the base cloth panel 2b on the inner side (passenger side) has a concave shape below the connecting portion 1c. The notch 2g is formed, and the extending portion 2c serving as the gas introducing portion 1d is sufficiently longer than the length of the gas introducing portion 1d, and the length L from a fold line 2d described later to the tip is, for example, The length is set to about 60 cm, and the peripheral portions are joined by joining means 3 such as sewing, bonding, welding, etc. in a state where the base cloth panels 2a and 2b are overlapped with each other to form a bag shape as a whole.

A base cloth panel 2 which becomes the front expansion chamber 1a
Between a and 2b are also joined by joining means 3 such as sewing, adhesion, welding, etc., so that, for example, internal connection portions 1g are formed at two places, and both sides of the extended portion 2c are joined by the joining means 3. By doing so, the extending portion 2c formed in a tubular shape as shown in FIG. 3 is folded inward from the folding line 2d shown by the broken line, and as shown in FIGS. 4 and 5, the outer portion 1h and the inner portion are formed. Double structure gas introduction part 1d consisting of 1i
Are formed.

Incidentally, in order to make it easier to fold the cylindrically formed extended portion 2c inward of the folding line 2d, (a) in FIG.
As shown in Fig. 7, notches 1j that do not reach the inside of the joining means 3 are formed on both ends of the folding line 2d, or
The cut 1j may be formed so as to traverse the joining means 3 as shown in FIG. 7, and as shown in FIG. 7C, a circular hole 1k may be formed at the tip of the cut 1j that does not reach the joining means 3. Of course, by forming these cuts 1j in advance, workability at the time of folding the extended portion 2c is improved.

Next, the operation of the curtain type airbag constructed as described above will be described.

When the two base cloth panels 2a and 2b shown in FIG. 2 are joined by the joining means 3, the tip end side of the cylindrical extending portion 2c is folded inward from the folding line 2d, and FIGS. 5
As shown in (1), a double-structured gas introduction portion 1d including an outer portion 1h and an inner portion 1i is formed.

Next, in mounting the bag body 1 on a vehicle, first, after folding the airbag body 1 into a predetermined shape, a gas introducing portion 1d provided at a rear end of the inflator 4 as shown in FIG. The gas inlet 4d is inserted to prevent gas from leaking from the fastening means 5 such as a band.
Tighten the outer circumference.

The airbag body 1 and the inflator 4 are fixed to the roof side above the side doors with the front end of the airbag body 1 attached to the front pillar or the like by the tension strap. The high-pressure gas generated from the inflator 4 due to the impact is ejected from the gas introducing portion 1d into the airbag body 1. The gas introducing portion 1d has a double structure including an outer portion 1h and an inner portion 1i. As a result, sufficient mechanical and thermal strength can be obtained even with respect to high temperature and high pressure gas ejected from the inflator 4, whereby the base cloth panel 2 constituting the airbag body 1 can have a low denier. Since the base cloth can be used and the low denier base cloth can be folded compactly, the airbag device can be downsized. The low denier base fabric here is, for example, a woven fabric of polyester or nylon 66, and has a 315 denier (360 dtex) or less.

FIG. 8 shows a modified example of the gas introducing portion 1d. An expanding portion 2f is formed at the tip of the extending portion 2c and the expanding portion 2f is folded inside the gas introducing portion 1d. The inner portion 1i is formed by the above, and by providing the inner portion 1i so that the expansion portion 2f reaches the vicinity of the gas inlet of the rear side expansion chamber 1b, the front side expansion chamber 1a and the rear side expansion chamber 1a are formed. Since it is possible to balance the flow rate of the gas flowing into the inflator 1b, the expansion chamber 1a on the front side farther from the inflator 4 is
It is possible to solve the problem that the expansion amount is insufficient. In addition, as shown in FIG. 3 and the like, the joining means 3 is formed linearly in the longitudinal direction of the gas introducing portion 1d.
Bend in a crank shape to the left and right of the fold line 2d, and
The diameter of i may be slightly smaller than that of the outer portion 1h.

Further, in the above-mentioned embodiment, an example in which the curtain type airbag is used has been described.
This is applicable to all airbags having d.

[0031]

As described in detail above, according to the present invention, by extending the tubular extending portion from the airbag body and folding the distal end side of the extending portion inward, the outer portion and the inner portion are formed. Since the gas introduction part of the multi-layered structure consisting of is formed, the gas introduction part of the multi-layered structure consisting of the outer part and the inner part can be obtained only by folding the tip side of the extension part inward. Compared to the one in which the air bag body and a base material that is a separate member are sewn into the air bag body to form the gas passages, the work of cutting and sewing the base cloth can be significantly reduced. As a result, workability is improved and the cost of the airbag device can be reduced.

Further, since the gas introducing portion has a multi-layer structure of the outer portion and the inner portion, the mechanical and thermal strength with respect to the high temperature and high pressure gas ejected from the inflator is improved. Since a low-denier base cloth can be used for the main body, which allows the airbag main body to be folded compactly, the airbag device can be downsized.

Further, since the notch is formed on the end side of the folding line that folds the extending portion inward, the notch does not reach the inner side of the joining means for joining both side edges of the extending portion or crosses the joining means. Since the tip end side of the extension portion can be easily folded inward from the folding line, workability is improved, and at the tip of the inner portion, an expansion portion having an enlarged cross-sectional area is formed, and the expansion portion is Since the inner portion is provided so as to be located in the vicinity of the gas inlet of the inflating portion, even if the airbag has a plurality of inflating chambers before and after the airbag body like the curtain type airbag, the expanding portion has Since the flow rates of the gas flowing into the front and rear expansion chambers are balanced, it is possible to solve the problem that the expansion amount of the front expansion chamber far from the inflator is insufficient.

[Brief description of drawings]

FIG. 1 is a plan view of an airbag according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a base fabric panel forming the airbag according to the embodiment of the present invention is unfolded.

FIG. 3 is a perspective view of a gas introducing portion provided in the airbag according to the embodiment of the present invention.

FIG. 4 is a plan view of a gas introducing portion provided in the airbag according to the embodiment of the present invention.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a cross-sectional view showing a state where an inflator is connected to a gas introduction portion provided in the airbag according to the embodiment of the present invention.

7 (a) to 7 (c) are explanatory views showing a modified example of the extension portion provided in the airbag according to the embodiment of the present invention.

FIG. 8 is a plan view showing a modified example of the gas introducing portion provided in the airbag according to the embodiment of the present invention.

[Explanation of symbols]

1 Airbag body 1a Expansion chamber 1b Expansion chamber 1d gas introduction section 1h outer part 1i Inner part 2c extension part 2d fold line 2f widening part 3 joining means 4 inflator

Claims (4)

[Claims] 1. An airbag comprising: an airbag main body having an expansion chamber; and a gas introduction portion provided in the airbag main body for introducing high-pressure gas ejected from an inflator into the expansion chamber. By extending a tubular extending portion from the airbag main body and folding the tip side of the extending portion inward, a gas introducing portion having a multilayer structure including an outer portion and an inner portion is formed. The characteristic airbag. 2. The notch according to claim 1, wherein a notch is formed on an end portion side of a fold line that folds the extension portion inward so as not to reach an inner side of a joining means that joins both side edges of the extension portion. Airbag. 3. The air according to claim 1, wherein a notch is formed on an end side of a fold line that folds the extending portion inward so as to cross a joining means for joining both side edges of the extending portion. bag. 4. An expansion part having a larger cross-sectional area is formed at the tip of the inner part, and the inner part is provided so that the expansion part is located near the gas inlet of the expansion part. The airbag according to any one of Items 1 to 3.