JPH11170944A - Airbag system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a sewn part of a tether to regulate the expansion of an airbag body in the width direction from being subjected to the heat. SOLUTION: An airbag device comprises an airbag body 1 formed to be a bag, an inflator which is provided in the airbag body, and ejects the gas when an impact is sensed, and inflates and develops the airbag body, a tether 6 which is sewn between a face base cloth and a back side base cloth 1b of the airbag body and inflates and develops the airbag body 1 to the prescribed shape by regulating the expansion of the airbag body in the width direction, and a protective piece 6a which is integrated with each end part of the tether 6, and is turned over with the pressure of the gas to be ejected from the inflator to cover the sewn part of the tether 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag apparatus in which a hanging string (tether) is provided between a front fabric and a back fabric of an airbag body so that the airbag body is inflated and deployed in a predetermined shape. About.

[0002]

2. Description of the Related Art Conventionally, airbag devices of various structures have been proposed and put to practical use, which are mounted on automobiles and protect occupants in the event of a collision.

For example, in Japanese Unexamined Patent Publication No. Hei 6-72267, the front-side base cloth greatly expands toward the occupant between the front-side base cloth and the rear-side base cloth of the airbag body. The suspension belt is provided with a length that is greater than the width of the airbag body when it is inflated, and the middle portion of the long belt portion is pinched and sewn. Since the wearing work can be easily performed, the workability is improved.

Japanese Patent Application Laid-Open No. 7-304411 discloses that
In order to easily and quickly sew the belt catch and the tip of the suspension belt, between the suspension belt member attached with the inflator and the belt catch provided in front of it,
When connecting with a plurality of suspension belt members, an airbag that sew the belt portion and the belt catch after inserting the positioning pin into the tip of the belt portion and the belt catch that sandwiches the belt portion from above and below, and positioning both. A method for manufacturing the body is described.

[0005]

In any of the above-mentioned conventional airbag systems, when any of the impacts due to the collision is sensed, the inflator instantaneously generates a large amount of gas, inflates the airbag body, and causes the occupant to receive the impact from the collision. It is configured to protect from.

However, in recent years, a combustion-type inflator in which the gas generating capacity is less likely to decrease even after a long period of time has been adopted.

In this combustion type inflator, heat is also generated when gas is generated, so that the gas generated from the inflator is sent directly into the airbag body to inflate and deploy the airbag body, as in the above-described conventional airbag apparatus. In such a configuration, the airbag base fabric near the insulator receives heat.

In particular, in a side collision airbag apparatus provided with a tether (suspension belt) for restricting inflation of the airbag body in the width direction in front of the inflator, high-temperature gas is directly applied to a sewn portion between the airbag body and the tether. Therefore, the sewn portion receives heat.

In view of the above, a separate cloth is applied to the sewn portion of the airbag and the tether to reinforce the sewn portion, or a flameproof cloth is provided in front of the inflator so that the high-temperature gas spouted from the inflator can be removed. Although measures are taken to prevent direct contact with the sewn part of the tether, these methods increase the number of parts and take time and effort to sew, resulting in increased costs and folding of the airbag body. Because it is bulky,
There were problems such as the airbag device becoming large.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and an airbag device integrally provided with a tether with a protective cloth for preventing gas ejected from an inflator from directly hitting a sewing portion of the tether. To prevent the seam of the tether from being damaged by heat damage.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, according to the present invention, when gas of an inflator hits both ends of a tether for restricting inflating of an airbag body in a width direction, a sewn portion of the tether is turned up. By providing a protective piece that covers the airbag, the high-temperature gas ejected from the inflator is prevented from directly hitting the sewn portion of the tether, and the sewn portion of the tether is not damaged by heat damage. The main body can be instantly expanded and deployed to a predetermined shape.

[0012]

According to the present invention, there is provided an airbag body formed in a bag shape, and provided in the airbag body and, when an impact is sensed, ejects a gas to blow the airbag body. An inflator for inflating and deploying the airbag body, a tether for connecting the front fabric and the back fabric of the airbag body to inflate and deploy the airbag body in a predetermined shape, and extending and forming both ends of the tether. When the airbag body is inflated and deployed, the airbag body includes a pair of protection pieces that cover the sewn portion of the tether.

With the above structure, when a high-temperature gas is ejected from the inflator toward the tether due to an impact at the time of a collision,
Since the protective cloth continuously provided at the end of the tether is turned up by the gas pressure and covers the sewn portion of the tether, there is no possibility that the sewn portion is damaged by heat damage by the high-temperature gas.

As a result, the airbag body instantaneously inflates and deploys into a predetermined shape, so that the occupant can be reliably protected from the impact at the time of collision.

According to a second aspect of the present invention, the width of the protection piece is larger than the width of the tether.

According to the above configuration, it is possible to reliably prevent the hot gas from the inflator from directly hitting the sewing portion of the tether.

According to a third aspect of the present invention, the protection piece is configured so that the tip end thereof is a free end and is turned up by gas pressure blown out by the inflator to cover the sewing portion of the tether. The present invention according to claim 4 further comprises:
The protective piece is formed by looping back to the inflator side, and sewn the tip end to the tether or sewed the tip end to each other. The gas can be reliably prevented from directly hitting the sewing portion of the tether.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIGS. 1 and 2 show an airbag device for a driver mounted on a steering handle or the like. The airbag device is formed in a bag shape by sewing around the front base cloth 1a and the back base cloth 1b. The airbag main body 1 is provided.

On the inner surface of the backing cloth 1b of the airbag main body 1, a substantially circular reinforcing cloth 2 having a mounting portion 2a integrally protruding at an opposing position, and a circular reinforcing cloth is provided at the center of the reinforcing cloth 2. The cloth 3 is sewn.

At the center of the reinforcing cloth 3, a mounting hole 3a penetrating to the back base cloth 1b is opened, and an inflator 4 is mounted in the mounting hole 3a from the lower surface side of the back base cloth 1b.

The inflator 4 has a cylindrical portion 4b having a plurality of ejection holes 4a formed on its peripheral surface. The cylindrical portion 4b is projected from the upper surface of the reinforcing cloth 3 into the airbag body 1. When a sensor (not shown) detects the impact at the time of the collision, a high-temperature gas is jetted into the airbag main body 1 from the jetting hole 4a, and the airbag main body 1 is instantly inflated and deployed.

Further, between the front base cloth 1a and the back base cloth 1b of the airbag main body 1, the airbag main body 1 is restricted from expanding in the width direction, and the airbag main body 1 is inflated and deployed in a predetermined shape. A tether 6 is provided.

The tether 6 is formed in a band shape with a base cloth made of the same material as that of the airbag body 1, and wide protective pieces 6a are formed integrally with the tether 6 at both ends. The vicinity of the boundary of the tether 6 is sewn in a loop shape to the attachment portion 2a of the reinforcing cloth 2 with the sewing thread 5.

The tip of the protective piece 6a is connected to the inflator 4
When the airbag body 1 is folded, the airbag body 1 is in close contact with the upper surface of the reinforcing cloth 2 as shown in FIG. When the hotter gas is ejected, the tip of the gas is turned up by the pressure of the gas, and covers the upper surface of the sewn portion as shown in FIG.

On the other hand, a circular wide portion 6b is formed at an intermediate portion of the tether 6, and the wide portion 6b is formed on the surface base cloth 1a.
Is sewn to the front base cloth 1a in a state of being in close contact with the inner surface of the base cloth.

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

The airbag body 1 is mounted inside the steering handle together with the inflator 4 in a folded state. When an impact sensor (not shown) detects the impact due to the collision, a high-temperature gas is discharged from the ejection hole 4 a of the inflator 4. The airbag body 1 is jetted into the main body 1 and the inflation and deployment of the airbag main body 1 is started.

The protection piece 6a at the end of the tether 6 which has been folded so as to be superimposed on the upper surface of the reinforcing cloth 3,
As shown in FIG. 4, the hot gas is turned up to cover the sewing thread 5 sewn to the mounting portion 2 a of the reinforcing cloth 2 so that the hot gas is prevented from directly hitting the sewing thread 5. can do.

Since the sewing portion of the tether 6 does not receive heat, the airbag main body 1 can be instantaneously inflated and deployed in a predetermined shape while restricting the expansion of the airbag main body 1 in the width direction. The driver can be reliably protected from the impact at the time.

Although the above embodiment is directed to a driver airbag device, the present invention can also be applied to a side collision airbag device for protecting an occupant from a side collision.

Next, an embodiment of a side collision airbag device will be described in detail with reference to the drawings shown in FIGS.

[0033] In the airbag body provided in FIG 10 is the side airbag apparatus, a main bag portion 10 ₁ for protecting the thorax of the occupant side collision, the sub-bag unit 10 to protect the occupant's head ₂ is formed into a bag shape by sewing around the front base cloth 10a and the back base cloth 10b so as to expand and deploy in a predetermined shape by gas generated from the inflator 14. .

[0034] Then with the inflator 14 is mounted in the air bag case so as to be positioned (not shown) in the main bag portion 10 _1, the main bag portion 10
_1, the boundary of the sub-bag unit 10 _2, though the partition wall 10c is formed on the partition wall 10c, the main bag portion 10
Communication hole 10d communicating between the ₁ and the sub bag portion 10 ₂ is formed.

[0035] The communication hole 10d, by gas generated from the inflator 14 to regulate the flow into the sub bag 10 in _2, is first inflated and deployed a main bag portion 10 _1, then the sub-bag 10 _{2 is made} to expand and deploy, and is formed by an orifice.

Meanwhile in the above air bag body 10, so that the inflated and deployed when the main bag portion 10 ₁ and the sub bag portion 10 ₂ is inflated and deployed immediately along the gap between the door 16 and the seat back 17, the air A plurality of tethers 12 are provided to regulate the inflation of the bag body 10 in the width direction.

As shown in FIG. 6, the tether 12 is formed in a band shape with a base cloth made of the same material as that of the airbag main body 10. It is sewn on the inner surface of the base cloth 10b.

Further, the tether 12 provided in front of the inflator 14 is directly hit by the high-temperature gas ejected from the inflator 14 and the tether 12 and the sewing thread 13 are damaged by heat. The length is formed to be approximately twice as long as the width of the airbag body 10 when the airbag body 10 is deployed, and this extended portion is used as a protection piece 12a. Has been folded back.

The protection pieces 12a are formed to be wider in advance than the vertical width of the tether 12 so that high-temperature gas from the inflator 14 does not directly hit the sewn portion of the tether 12, and the end of each protection piece 12a is formed. The parts are sewn to the center of the front surface of the tether 12 with sewing thread 15 in a state of being overlapped with each other.

Next, the operation of the side collision airbag device configured as described above will be described.

In normal times, the airbag body 10 is stored in a folded state in an airbag case buried in the upper side of the seat back 17, and in this state, a sensor (not shown) detects an impact at the time of a side collision. Then, a large amount of gas from the inflator 14 is generated, is ejected toward the tether 12 as shown in FIG. 7, the main bag portion 10 ₁ of the airbag body 10 starts inflation, the front side of the inflator 14, Since the protection piece 12a is folded back in a loop shape,
The high-temperature gas directly hits this protective piece 12a, and the tether 12a
Does not hit the sewing thread 13 sewn to the airbag body 10.

[0042] Thus for never sewn portion of the tether 12 may be damaged by heat damage, to regulate the expansion of the width direction of the main bag portion 10 _1, the main along the gap between the door 16 and the seat back with the bag portion 10 ₁ is quickly inflated and deployed, the gas is expanded deployed main bag portion 10 _1, and flows from the communication hole 10d into the sub-bag unit 10 _2, the sub-bag unit 10 ₂ in FIG. 8 Inflate and deploy as shown.

[0043] The main bag portion 10 ₁ protects the occupant's chest from an impact of a side collision First, followed by the sub-bag unit 1
0 ₂ to protect the occupant's head makes it possible to reliably protect an occupant from an impact of a side collision.

Since the end of the protection piece 12a is sewn to the center of the front surface of the tether 12, the end of the protection piece 12a is not twisted by the high-temperature gas, so that the sewn portion of the tether 12 can be reliably protected. .

In the above embodiment, the protection piece 12a is sewn to the tether 12 in a state where the end of the protection piece 12a is overlapped, but the end of the protection piece 12a is separately sewn to the front of the tether 12 as shown in FIG. The same effect can be obtained by sewing the ends of the protective pieces 12a to each other as shown in FIG.

[0046]

As described above in detail, according to the present invention, protection pieces are formed at both ends of a tether for restricting inflation of a front base fabric and a back base fabric constituting a body of an airbag in a separating direction. hand,
When the airbag body is inflated and deployed, the protection piece covers the sewn portion of the tether, so that the sewn portion of the tether can be prevented from receiving heat.

As a result, the airbag body is inflated and deployed in a predetermined shape, so that the occupant can be reliably protected from an impact in the event of a collision.

Further, since the protection piece is wider than the tether, it is possible to reliably prevent the high-temperature gas spouted from the inflator from directly hitting the sewn portion of the tether, and a separate cloth is attached to the sewn portion of the tether. Since no work such as sewing is required, the number of parts can be reduced, and the man-hour required for the sewing work can be reduced, so that the cost of the airbag device can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a tether provided on an airbag body of an airbag device according to an embodiment of the present invention.

FIG. 2 is a perspective view of the vicinity of an inflator provided in an airbag body of the airbag device according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view of the airbag device according to the embodiment of the present invention.

FIG. 4 is an operation explanatory view of the airbag device according to the embodiment of the present invention;

FIG. 5 is a development view of an airbag main body provided in a side collision airbag device according to another embodiment of the present invention.

FIG. 6 is a perspective view of the vicinity of a tether of an airbag main body provided in a side collision airbag device according to another embodiment of the present invention.

FIG. 7 is an operation explanatory view of a side collision airbag device according to another embodiment of the present invention.

FIG. 8 is an operation explanatory view of a side collision airbag device according to another embodiment of the present invention.

FIG. 9 is an explanatory view showing a modification of the protection piece of the airbag device according to the embodiment of the present invention.

FIG. 10 is an explanatory view showing a modification of the protection piece of the airbag device according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Airbag main body 1a Front base cloth 1b Back base cloth 2 Reinforcement cloth 2a Attachment part 3 Reinforcement cloth 3a Mounting hole 4 Inflator 4a Spray hole 5 Sewing thread 6 Tether 6a Protective piece 10 Airbag main body 10 ₁ Main bag part 10 ₂ Subbag Part 10a Front base cloth 10b Back base cloth 10c Partition wall 10d Communication hole 12 Tether 12a Protective piece 13 Sewing thread 14 Inflator 15 Sewing thread 16 Door 17 Seat back

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Michitaka Suzuki 218 Aoshima-cho, Fuji-shi, Shizuoka Japan Nippon Plastics Co., Ltd.

Claims (4)

[Claims] 1. An airbag body formed in a bag shape, an inflator provided in the airbag body and inflating and deploying the airbag body by blowing gas when an impact is detected, and the airbag body. A tether for inflating and deploying the airbag body into a predetermined shape by connecting the front base cloth and the back base cloth to each other; and sewn the tether when the airbag body is inflated and deployed by extending both ends of the tether. An airbag device, comprising: a pair of protection pieces covering a fitting portion. 2. The airbag device according to claim 1, wherein the width of the protection piece is larger than the width of the tether. 3. The protection piece has a tip portion as a free end,
3. The airbag device according to claim 1, wherein the inflator is turned up by a gas pressure ejected to cover a sewing portion of the tether. 4. The protection piece according to claim 1, wherein the protection piece is folded back in a loop shape toward the inflator, and its tip is sewn to the tether or the tip is sewn to each other. Or the airbag device according to 2.