JPH06321038A - Air bag - Google Patents

Abstract

PURPOSE:To effectively protect a human body from a shock at the time of collision. CONSTITUTION:First, second, and third foundations 1, 2, 3 are sewn to form an air bag main body 4. The first and second fuoundations 1 and 2 have a circular, the peripheral edge parts of which are sewn, and the fitting hole 8 of a gas generator 7 is opend at the middle in the first foundation 1. The foundation surface of the second foundation 2 is a buffer surface to a human organism. The third foundation 3 has a tubular state wherein one side is diameter-enlarged, a small-diameter side is sewn to the mouth edge of the fitting hole 8 of the first foundation 1, and a large-diameter side is sewn to the foundation surface of the second foundation 2 to demarcate the inside of the air bag main body 4 into first and second chambers 5 and 6. In the third foundation 3, a vent hole 11 is opened in part of the foundation surface to communicate the first chamber 5 and the circumferential second chamber 6 into the tube of the third foundation 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in an interior of a vehicle, particularly in a steering wheel, and inflates and expands when a high-pressure gas is applied in the event of a collision of the vehicle.
An airbag that protects a vehicle from an impact.

[0002]

2. Description of the Related Art There are two types of airbags for passenger protection of automobiles, one for the driver's seat and the other for the passenger seat. When an accident such as a collision occurs, high temperature and high pressure gas is blown into the bag to rapidly It inflates and deploys to suppress the occupant's face and protect it from the impact of a collision.

The airbag is usually folded, and the front of the seat and that of the driver's seat are usually stored in the steering wheel. Conventionally, an airbag is part of the body,
A vent hole that communicates with the outside air is opened, and high-temperature, high-pressure gas is blown into the interior of the airbag body to rapidly inflate it.
It is common to have a structure in which the high-pressure gas inside is discharged through the vent hole after the expansion.

[0004]

However, in the above structure, when the gas generator is actuated by the impact of the collision of the airbag body and the high pressure gas rapidly inflates and expands due to the inflow of high pressure gas, at the same time, the high pressure is released from the vent hole. Since the gas is discharged into the outside air to start contraction, the contraction timing becomes a big problem. For example, if the airbag body is already contracted when the occupant is shaken back due to a secondary or tertiary collision or a recoil at the time of the collision, the original cushioning effect when the occupant leans forward due to the collision recoil. Can't get

In order to solve this problem, in the airbag which expands and expands by the gas generated from the gas generator and then releases a part of the contained gas to absorb the impact force of the human body, the upper half of the bag base cloth is absorbed. There is proposed an air bag with an auxiliary bag (see Japanese Patent Laid-Open No. 4-212651), characterized in that it includes at least one flexible bag containing a part or all of a vent hole and a gas released therefrom. . With this structure, the mist in the gas injected from the gas generator does not scatter in the vehicle, and the gas remains trapped in the bag, so that the cushioning effect can be maintained for a relatively long time.

However, the above structure has a form in which the auxiliary bag is further stacked on the cushioning surface of the ordinary airbag, and high-pressure gas is rapidly blown into the ordinary airbag to inflate and deploy the ordinary airbag. After that, gas will flow into the auxiliary bag through the vent hole. Originally, the function of the airbag is to fix the occupant's head with the pressure of the airbag that expands to the maximum when the first impact at the time of a collision is applied. The cushioning surface of the auxiliary bag, which is still insufficient, will support the occupant's head, and the head may be insufficiently fixed. However, after that, the gas press-fitted into the normal airbag flows into the auxiliary bag and the pressure is lowered as a whole, and the cushioning property (cushioning property) against the subsequent impact reaction is:
No problems are expected.

An object of the present invention is to provide an air bag that secures the head of an occupant with sufficient pressure against the impact at the time of a collision, and provides appropriate cushioning against the next recoil. is there.

[0008]

In order to achieve the above object, the airbag according to the present invention is configured such that the first base cloth, the second base cloth and the third base cloth are adhered to each other and the inside of the airbag main body is adhered. An airbag divided into two chambers, wherein the first and second base fabrics are
It has a disk shape and is adhered at the peripheral portion. The first base cloth has a mounting hole for mounting a gas generator at the center, and the second base cloth forms a cushioning surface for the human body during expansion and expansion. The third base cloth has a cylindrical shape, and a vent hole is opened in a part of the peripheral surface of the cylinder, and one opening edge of the cylinder is bonded to the opening edge of the mounting hole of the first base cloth. And the other end opening edge is the second
Adhered to the cloth surface of the base cloth, the first chamber of the airbag body is a space surrounded by the inner surface of the third base cloth and the second base cloth,
The second chamber is a space surrounded by the first and second base fabrics and the outer surface of the third base fabric, and is formed around the first chamber.
The volume of the chamber is larger than the volume of the second chamber, the first chamber and the second chamber communicate with each other through the vent hole of the third base cloth, and the vent hole allows the high pressure gas blown into the first chamber to flow into the first chamber. It is a small hole that flows into two chambers.

Further, the tubular shape of the third base cloth is such that one opening edge is expanded and the expanded opening edge is adhered to the cloth surface of the second base cloth.

[0010]

When the gas generator operates due to the impact of a vehicle collision, the high-pressure and high-temperature gas generated fills the first chamber and tensions the second base cloth with sufficient pressure, and the buffer surface and seat Fix the occupant's head between them. After that, the gas in the first chamber flows out to the surrounding second chamber through the vent hole, the tension of the cloth surface of the second base cloth is relaxed, and a preferable cushioning property against the reaction of the shock is obtained. The bonding between the base fabrics includes sewing, welding, and bonding by using an adhesive.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. Referring to FIG. 1, an airbag according to the present invention has an airbag body 4 formed by combining a first base cloth 1, a second base cloth 2 and a third base cloth 3 in the airbag body 4. The first
It is divided into a chamber 5 and a second chamber 6. As the base fabrics 1 and 2, coated fabrics obtained by coating nylon fabric with silicon were used, but the fabrics are not necessarily limited to these, and any sheet having air permeability, heat resistance, and pressure resistance may be used.

In FIG. 2, first and second base cloths 1 and 2 are provided.
Is cut into a circular shape, and the outer edges of both base fabrics are folded back and the peripheral edge portion is sewn to form a bag of the airbag body 4.

The first base cloth 1 is used on the side where the gas generator (inflator) 7 is mounted, and a circular mounting hole 8 for mounting the gas generator 7 is opened in the center of the cloth surface.

The second base cloth 2 is the surface of the airbag body 4 and is cut into a circle, and the cloth surface is a cushioning surface for supporting a part of the human body of the occupant, for example, the face.

The third base cloth 3 is sewn into a tubular shape with both ends open, and the shape of the tubular shape is such that one opening edge side is expanded and the shape is substantially a truncated cone. It has a cylindrical shape. The diameter of the opening on the small diameter side is the same as that of the mounting hole 8 opened in the first base cloth 1, and the opening edge 9 is overlapped with the rim of the mounting hole 8 from the inner surface of the first base cloth 1. It is sewn together and also serves to reinforce the mounting hole 8. The opening edge 10 on the large diameter side is concentrically sewn to the cloth surface near the peripheral edge of the second base cloth 2 in a state where the opening edge 10 is expanded to the maximum diameter around the mounting hole 8.

In the present invention, the first chamber 5 is a space surrounded by the tube of the third base fabric 3 in the airbag body 4, and the second chamber 6 is the outer periphery of the base fabric 3 and the first base fabric 3. And the second base fabrics 1 and 2
It is a space surrounded by spaces.

A vent hole 11 is opened in a part of the cloth surface of the third base cloth 3 so that both chambers 5 and 6 communicate with each other.

The vent hole 11 is a small hole that allows the high-pressure gas blown into the first chamber 5 to gradually flow out to the second chamber 6.

In the embodiment, the gas generator 7 is integrally attached to the attachment hole 8 of the airbag body 1, and the airbag body 1 is folded and incorporated into the front of the seat of the automobile, for example, the steering wheel. . When an accident such as a collision of a car occurs, the gas generator 7 receives the impact and emits high-temperature, high-pressure gas, which gas is blown into the first chamber 5 and the first chamber 5 rapidly expands and expands. The gas pressure acts on the second base cloth 2 to tension the buffer surface, supporting the head of the occupant and fixing it to the pillow of the seat.

The high-pressure gas filling the first chamber 5 then flows out into the surrounding second chamber 6 through the vent hole 11, the tension of the buffer surface is relaxed, and the shock is recoiled due to the recoil.
It provides an appropriate cushioning property to the occupant's face, and at the same time, the second chamber 6 around the first chamber 5 expands to increase the surface area of the airbag body 1 and to prevent the head from swinging due to the recoil of impact over a wide area. Can support.

The following comparative tests were conducted to demonstrate the effect of the present invention.

(Test Example 1) As shown in FIG.
The base cloth 21 and the second base cloth 22 are sewn together at the peripheral edge to
The performance of the airbag (conventional airbag) in which the vent hole 23 is opened on the cloth surface of the base fabric 21 is compared with the airbag of the present invention. The experiment was carried out by incorporating each airbag into the steering wheel of the actual vehicle, placing a dummy on the driver's seat, and colliding the actual vehicle at high speed with a screen.

According to the conventional air bag, after inflating and expanding, high temperature and high pressure gas is discharged to the outside through the vent hole 23, the air bag is contracted, and the steering wheel and the gas generator of the gas generator are passed through the base cloth surface of the air bag. Although it touched the hard surface, according to the airbag of the present invention, the high temperature and high pressure gas is not discharged to the outside, and the dummy does not completely squeeze.
The cushioning effect of the airbag did not touch the hard surfaces of the steering wheel or gas generator.

(Test Example 2) For comparison, as shown in FIG. 3 (b), a tape was used as the third base cloth 24, and both ends of the tape were the first base cloth 21 and the second base cloth 22. A comparative air bag (comparative example) sewn on the opposite surfaces of the above was made, and the performances of this comparative example and the air bag of the present invention were compared. According to the comparative example, the high temperature and high pressure gas leaks from the sewn portion between the third base cloth 24 and the second base cloth 22, and the gas directly hits the dummy's face. Although gas leaked in the bag, the gas did not hit the dummy's face directly.

Gas leakage from the seams is unavoidable as long as only the base cloth is sewn. However, by making the sewn portion the outer peripheral edge of the second base cloth which serves as a buffer surface, the leaked gas can be prevented. Avoid direct hits to prevent facial burns and gas inhalation.
However, if the sewn portion is coated with resin, or if airtight sealing is performed by using adhesion and welding together, no gas leakage will occur.

[0026]

As described above, according to the present invention, the high temperature and high pressure gas emitted from the gas generator is received in the first chamber, and the high pressure gas is applied to the cloth surface of the second base cloth which serves as a buffer surface for the human body. Since it is directly actuated, it can be expanded and deployed without imbalance with respect to the impact at the time of collision, and the buffer surface can be tensioned to fix the human head, and the diameter of the cylinder of the third base cloth can be fixed. Since it expands the diameter and adheres it to the second base cloth, it supports the occupant's face in a large area, and there is no risk of direct burn of gas leaking from the seams causing burns on the face, and gas from the nose There is no danger of inhaling.

Further, the high temperature, high pressure gas received in the first chamber flows out to the surrounding second chamber through the vent hole, so the tension of the buffer surface is relaxed with a time delay after expansion and expansion, and the effective surface area is expanded. Thus, the occupant's face can be effectively protected from being shaken back by the reaction of the impact.

Further, even if the third base cloth is unbonded due to the shocking pressure at the time of expansion, the high temperature and high pressure gas does not flow out of the airbag, which is safe.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view.

FIG. 3 shows an airbag used in a test example.
(A) is a conventional type, (b) is an airbag of a comparative example.

[Explanation of symbols]

 1 1st base cloth 2 2nd base cloth 3 3rd base cloth 4 Airbag body 5 1st chamber 6 2nd chamber 7 Gas generator 8 Mounting hole 9 Small diameter side opening edge 10 Large diameter side opening edge 11 Vent hole

Claims (2)

[Claims] 1. An airbag in which the inside of an airbag body is divided into two chambers by adhering a first base cloth, a second base cloth and a third base cloth to each other. The cloth has a disk shape and is adhered at the peripheral portion, the first base cloth has a mounting hole for mounting the gas generator at the center, and the second base cloth has a cushioning surface against the human body during expansion and deployment. The third base cloth has a tubular shape, a vent hole is opened in a part of the peripheral surface of the cylinder, and one end opening edge of the cylinder is an opening of the attachment hole of the first base cloth. The other end opening edge is adhered to the cloth surface of the second base cloth, and the first chamber of the airbag body is surrounded by the inner surface of the third base cloth and the second base cloth. The second chamber is a space surrounded by the first and second base fabrics and the outer surface of the third base fabric, and is formed around the first chamber.
The volume of the chamber is larger than the volume of the second chamber, the first chamber and the second chamber communicate with each other through the vent hole of the third base cloth, and the vent hole allows the high-pressure gas blown into the first chamber to flow into the first chamber. An airbag characterized by a small hole that flows into two chambers. 2. The tubular shape of the third base cloth is such that one opening edge is expanded and the expanded opening edge is bonded to the cloth surface of the second base cloth. The airbag according to claim 1, wherein: