JP2529289Y2 - Bag for airbag device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bag used for an airbag device for a vehicle, and more particularly, to a bag for an airbag device obtained by sewing two superposed base fabrics along a peripheral portion thereof. About the body.

[0002]

2. Description of the Related Art Conventionally, when an impact of a predetermined value or more is detected due to a collision of a vehicle, a bag is inflated and expanded in a vehicle interior by high-pressure gas, and the occupant is subjected to a shock from a secondary collision by a cushioning action of the bag. 2. Description of the Related Art Protected airbag devices are known. Such an airbag device is mounted on a central portion of a steering wheel or an instrument panel, and protects occupants in a driver's seat and a passenger seat, respectively. A bag body used in this type of airbag device has a circular first base cloth positioned on the front side of the vehicle body and connected to a gas generator of the airbag device, and a circular shape positioned on the rear side of the vehicle body and in contact with an occupant. Is formed in a bag shape by overlapping the second base cloth and sewing the peripheral portion thereof.

[0003] By the way, in the bag body of the above-mentioned conventional airbag device, a seam allowance protrudes outside a sewing line where the first base cloth and the second base cloth are sewn, so that the rigidity of the seam allowance is the other part of the bag body. And the rigidity of the entire bag becomes non-uniform. Then, after sewing the first base cloth and the second base cloth, the bag body is turned upside down using a circular opening for coupling to the gas generator formed at the center of the first base cloth, One that accommodates the above-mentioned seam allowance in the bag body has been proposed by the present applicant (Japanese Patent Laid-Open No. 2-17 / 1990).
No. 5353).

[0004]

However, if the first and second base fabrics are sewn and then reversed as described in the above-mentioned publication, the number of man-hours for manufacturing the bag body increases and the manufacturing cost increases. There is.

The present invention has been made in view of the above circumstances, and has as its object to provide a bag for an airbag device having uniform rigidity at low cost.

[0006]

In order to achieve the above object, according to the present invention, two superposed base fabrics are sewn together at a sewing line along a peripheral portion thereof, and a seam allowance is formed outside the sewing line. In the air bag device bag body comprising
A plurality of slits are radially formed in the seam allowance of the base cloth.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

1 to 5 show an embodiment of the present invention. FIG. 1 is a sectional view of a vehicle showing an operation state of an airbag device, and FIG. 2 is a sectional view taken along line 2-2 of FIG. 3 is 3-3 in FIG.
FIG. 4 is a sectional view taken along line 4-4 of FIG. 1, and FIG. 5 is a perspective view of a main part of the bag body.

As shown in FIG. 1, the airbag device inflates and deploys the bag body 2 from the center of the steering wheel 1 toward the passenger compartment at the time of a collision of the vehicle V, and restrains the occupant M sitting in the driver's seat S. To protect from the impact of a secondary collision.

As shown in FIGS. 2 and 3, a steering wheel 1 is mounted on an outer periphery of a mounting base 3 fixed to a tip of a steering shaft via an arm 4.
A module 6 including a gas generator 5 and a bag 2 is attached to the center of the steering wheel 1.
That is, a cup-shaped metal container 7 is mounted on the mounting base 3, and an opening formed at the center of the bottom is provided with an explosive for generating combustion gas and an electric charge for igniting the explosive. A gas generator 5 composed of a detonator is mounted. The folded bag 2 is hermetically mounted on the mounting base 7a formed on the outer periphery of the opening of the container 7 so as to surround the outer periphery of the gas generator 5. Inflate and expand with gas.

The surface of the module 6 is covered with a synthetic resin module cover 8 also serving as a pad. Inside the module cover 8 is a synthetic fiber reinforcing net 10 whose outer periphery is locked by a plurality of hooks 9. Is buried integrally. Then, the module cover 8 is attached to the center of the steering wheel 1 by fastening the base of the hook 9 to the outer periphery of the container 7 with a bolt 11.

On the surface of the module cover 8, two upper and lower horizontal grooves 8a, two left and right vertical grooves 8b, and a central groove 8c extending substantially parallel to the center of the horizontal groove 8a are formed. The reinforcing net 10 corresponding to the H-shaped area (the area shown by the broken line in FIG. 2) along the vertical groove 8b and the central groove 8c is partially cut off, and furthermore, on the back side of the module cover 8 in this area By providing the cuts, the strength of this portion is particularly reduced.

Next, the structure of the bag 2 will be described with reference to FIGS. The bag 2 is made of a soft cloth coated with a gas permeation prevention coating, and is located on the steering wheel 1 side, that is, on the front side of the vehicle body when the bag 2 is deployed, and has a circular first opening 12a formed in the center. Base cloth 1
2 and a circular second cloth having the same diameter as the first base cloth 12.
The base cloth 13 is formed by overlapping the base cloths 13 and sewing the outer peripheral parts of the base cloths 12 and 13 while leaving a seam allowance 14 having a predetermined width. A ring-shaped reinforcing cloth 15 and a heat-resistant ring-shaped flameproof cloth 16 are overlapped and bonded to the outside and the inside of the opening 12a of the first base cloth 12, respectively.
Two vent holes 12 b for discharging excess combustion gas when the bag body 2 is deployed are formed in the first base cloth 12.
A large number of slits 14a extending in the radial direction of the bag body 2 are formed on the seam allowance 14 of the base fabrics 12, 13, that is, outside the sewing line 17, so that the rigidity of the seam allowance 14 of the bag body 2 is reduced. It is planned.

The bag 2 constructed as described above has a metal pressing ring 1 around the opening 12a of the first base cloth 12.
8 and the mounting base 7 a around the opening of the container 7, and is fixed by a plurality of rivets 19. That is, the rivet 19 penetrates the press ring 18, the flameproof cloth 16, the first base cloth 12, the reinforcing cloth 15, and the mounting base 7a, and fastens them together.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

When the sensor that detects the collision of the vehicle V outputs an explosion signal of the airbag device, the explosion device of the gas generator 5 operates to ignite the explosive, and the supplied high pressure combustion gas is supplied to the bag. Body 2 begins to inflate. When pressure is applied to the inner surface of the module cover 8 due to the expansion of the bag body 2, the module cover 8 is moved along the vertical groove 8b and the central groove 8c.
It breaks in the area of the shape and expands outwards with the lateral groove 8a as a hinge. Then, the bag body 2 is connected to the module cover 8.
From the opening formed by the widening of the vehicle, and expands into a position interposed between the occupant M and the steering wheel 1 as shown in FIG. As a result, the occupant M is restrained by the unfolded bag 2, and a secondary collision with the steering wheel 1 and the windshield glass is avoided. At this time, even if the seam allowance 14 of the unfolded bag body 2 contacts the occupant M,
Since the rigidity of the seam allowance 14 is reduced by the large number of slits 14a, the occupant M can be restrained with a soft touch.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the present invention described in the claims for utility model registration. It is possible to make design changes.

For example, the present invention is also applicable to an airbag device which is deployed from the instrument panel into the vehicle interior and restrains the occupant in the passenger seat. In addition, the present invention is not limited to an airbag device using combustion gas of explosives, but is also applicable to an airbag device that deploys a bag with high-pressure gas stored in a cylinder.

[0019]

As described above, according to the present invention, a plurality of slits are radially formed in the seam allowance located outside the sewing line of the two base fabrics constituting the bag body, thereby increasing the rigidity of the seam allowance. It can be lowered to make it as flexible as the rest of the bag. This makes it possible to soften the feel of the sewing allowance even if the sewing allowance comes into contact with the occupant when the bag is deployed. In addition, since the step of inverting the bag is not required in the production, the production cost of the bag can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a vehicle showing an operation state of an airbag device.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 1;

FIG. 5 is a perspective view of a main part of the bag body.

[Explanation of symbols]

 12 ... 1st base cloth (base cloth) 13 ... 2nd base cloth (base cloth) 14 ... sewing margin 14a ... slit 17 ... sewing line

Claims (1)

(57) [Scope of request for utility model registration] 1. Two superposed base fabrics (12, 13)
Is sewn on a sewing line along the periphery thereof (17),
In a bag for an airbag device having a seam allowance (14) formed outside the sewing line (17), a plurality of slits (14a) are radially formed in a seam allowance (14) of the base fabrics (12, 13). Characterized by
Bag for airbag device.