JPH1076908A - Air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make possible quick, reliable development of an air bag by preventing surplus gas from leaking outside through a vent hole before high pressure gas necessary and enough for protecting an occupant is secured in the air bag. SOLUTION: A bag-shaped air bag 1 is provided with an inflater 5 fitted in an opening 4 for the inflater bored in the approximate center of the air bag. A vent hole 8 is bored in an appropriate position on the air bag 1, with a valve member 9 attached to close the vent hole 8 so that part 10B where the valve member 9 is attached peels off by the action of a predetermined internal pressure of the air bag 1 at the time of developing action of the air bag 1 to open the valve member 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag installed in a driver's seat, a passenger's seat, a side seat, a rear seat, or the like for protecting an occupant of an automobile or the like, and appropriately releases high-pressure gas when the airbag is deployed. Of the vent hole provided for the purpose.

[0002]

2. Description of the Related Art In recent years, the proportion of automobiles that employ airbags for steering wheels, passenger seats, and the like to protect occupants has increased, and many types of airbags have been proposed. An airbag used to protect an occupant of a vehicle is, for example, typically installed in a driver's seat. Usually, a backing cloth located on the vehicle body side such as a steering wheel and a front cloth located on the occupant side have an outer periphery thereof. The parts are joined by suturing or the like to form a bag. Then, in the event of a collision, the bag-shaped airbag is deployed and inflated by high-pressure gas generated from an inflator that operates by detecting deceleration.
At this time, a vent hole for releasing excess gas to the outside of the airbag is usually formed in an appropriate portion of the airbag after securing a necessary and sufficient internal pressure for occupant protection. FIG. 5 shows an example of such a device. Explaining this, the airbag 21 is composed of an outer material 22 on the occupant side and a lining 23 on the vehicle body side, which are joined by stitching portions of their peripheral edges to form a bag shape. An opening 24 for an inflator reinforced by a reinforcing body 26 is formed substantially at the center, so that an inflator (not shown) can be mounted. The reinforcing member 2 is provided at an appropriate portion of the lining 23.
A plurality of circular vent holes 28 whose periphery is reinforced by 9 are formed. Thus, when the airbag is deployed and inflated, the excess gas can be released from the airbag while securing a necessary and sufficient internal pressure for protecting the occupant.

[0003]

However, in such a conventional airbag, only a circular hole having a predetermined radius is formed as a vent hole, and fine adjustment of the internal pressure of the airbag is performed. Was impossible. For this reason, it is not without danger that the high-pressure gas escapes to the outside of the airbag before securing a necessary and sufficient internal pressure for protecting the occupant in the airbag. Therefore, it is necessary to make the total amount of gas generated from the inflator larger than the volume of the airbag, and it has been difficult to reduce the amount of gas generated by the inflator and to reduce the weight and size of the inflator.

Therefore, the present invention solves the above-mentioned problems in the conventional airbag, and until the high pressure gas necessary and sufficient for protecting the occupant is secured in the airbag, the surplus gas from the vent hole is removed. Provided is an airbag capable of quickly and surely deploying an airbag without leakage to the outside of the airbag.

[0005]

SUMMARY OF THE INVENTION Therefore, according to the present invention, a vent hole is formed at an appropriate position of an airbag in a bag-shaped airbag having an inflator mounted in an inflator opening formed substantially in the center. At the same time, a valve element is attached so as to close the vent hole, and a part of the attached part of the valve element is peeled off by the action of a predetermined airbag internal pressure during the airbag deployment operation, so that the valve element opens. It is characterized by having been constituted so that. The present invention also provides a bag-shaped airbag in which an inflator is attached to an inflator opening formed substantially in the center, and a perforation along a shape of the valve body to define a valve body at an appropriate position of the airbag. The perforation is broken by the action of a predetermined airbag internal pressure during the operation of deploying the airbag, and the valve body is opened, thereby solving these problems. Means.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a first embodiment of the present invention. FIG. 1 (A) is a cross-sectional view of a half of an airbag device, and FIG. 1 (B) is a bottom view of a vent hole viewed from an arrow A. 1 (C) is an A perspective view showing the operation of the vent hole. FIG. 2A is an overall perspective view of a partially cut airbag device from which an inflator is omitted, and FIG. 2B is a bottom view as viewed in the direction of arrow B. As shown in FIGS. 1 (A) and 2 (A), the airbag 1 has an inflator opening 4 formed substantially in the center thereof, and a periphery of the inflator opening 4 which is joined and reinforced by a plurality of layers of reinforcing bodies 6. The outer peripheral portion of the lining 3 is joined to the outer peripheral portion of the outer material 2 on the occupant side disposed opposite to the lining 3 to form a bag-like shape. The inflator 5 to be supplied is inserted. The inflator 5 is attached to a base plate 12 fixed to a steering shaft or the like (not shown) so that the lining 3 joined and reinforced by the reinforcing member 6 and the base plate 12 are sandwiched by a retainer 7.

In this embodiment, FIGS. 1A and 2
As shown in FIG. 1, a plurality of (two in the illustrated example) circular vent holes 8 are formed at appropriate positions on the lining 3 of the airbag 1 and the lining 3 is closed as if these vent holes 8 were closed. Are provided with valve bodies 9 and 9 on the outside thereof. As understood from FIG. 1B, which is a view taken in the direction of arrow A in FIG. 1A, the valve element 9 attached to the outside of the lining 3 so as to close the vent hole 8 is slightly larger than the vent hole 8. It is formed large and attached and fixed to the main body lining 3 of the airbag 1 at a plurality of locations (three locations in the illustrated example) by spot welding 10 or the like. The present invention relates to the attachment of the valve body 9,
In the present embodiment, a part of the attached portion of the valve body 9 is peeled off by the action of a predetermined airbag internal pressure during the deployment operation of the airbag 1 and the valve body 9 is opened. In this case, the valve body 9 is attached to the lining 3 of the airbag body by a strong welding portion 10A and a peeling portion 10B having a relatively low adhesive force. The additional attachment of the valve body 9 to the backing 3 is performed by heat welding such as high-frequency welding that can easily obtain a relatively uniform adhesive force between the valve body 9 and the backing 3. The difference in the adhesive force between the welding portion 10A and the peeling portion 10B may be caused by the difference in the welding area, and although not described in detail, the peeling portion 10B is formed by interposing a material having a difference in the heat welding force. Can be adopted to reduce the adhesive strength, that is, the welding power.

In the present invention, the outer material 2 and the lining 3 of the airbag 1 are stretchable films having excellent heat-welding properties such as high-frequency welding, for example, thermoplastic elastomers such as urethane, ester-based thermoplastic elastomers, and amides. A thermoplastic film such as a thermoplastic elastomer or a synthetic fiber woven fabric such as a polyamide (eg, polyamide 6 or polyamide 66), polyester, or polyimide is used. When a thermoplastic elastomer such as urethane is used for the outer material 2 and the lining 3 of the airbag 1, the valve body 9 is also made of the same material that can provide a high heat welding force, that is, a thermoplastic elastomer such as urethane. Is done. Also,
When a synthetic fiber woven fabric such as polyamide is used for the outer material 2 and the lining 3 of the airbag 1, the same material capable of similarly obtaining a high heat-welding force, that is, a synthetic fiber woven fabric such as polyamide or a heat-generating material such as urethane is used. The valve body 9 is also constituted by a plastic film. When attaching the valve body 9 to the airbag body, the same material as the lining 3 as the airbag body and the valve body 9 are selected from the above-mentioned materials to obtain a strong welded portion 10A, and the peeling portion 10B is provided. May be used in combination of different materials.

With this configuration, in the event of a collision, the high-pressure gas generated from the inflator 5 that operates upon detection of deceleration blows out into the bag-shaped airbag 1 to inflate the airbag 1. As shown in Fig. 1
As shown in (A), the high pressure gas necessary and sufficient for the protection of the occupant is provided inside the airbag 1 and is provided outside the vent hole 8 until the airbag 1 is sufficiently inflated. The vent hole 8 is closed by the presence of the valve body 9 and the high pressure gas does not leak out of the airbag, so that the airbag 1 is quickly and reliably inflated and deployed.
Thereafter, as shown in FIG. 1 (C), at the stage where the airbag 1 is inflated and the internal pressure necessary and sufficient for protecting the occupant is obtained, the internal pressure (black arrow in the drawing) is further increased by excess gas. Further, when the occupant abuts on the airbag to further increase the internal pressure of the airbag, a valve opening action is performed at the spot welding portion 10 of the valve body 9 to the lining 3. That is, the peeling portion 10B set to an adhesive force such that the peeling is performed by a predetermined internal pressure in the airbag 1 peels off, and the valve body 9 opens with the welded portion 10A additionally attached and fixed by the strong adhesive force as a fulcrum. Then, the surplus gas is quickly released from the airbag 2 through the vent hole 8 as indicated by a white arrow. This means that the inside of the airbag 1 has been regulated at a predetermined pressure. At this time, the lining 3 of the valve body 9 other than the peeling portion 10B
The 10 parts of the spot welded to each other are firmly bonded by thermal welding of the same material and do not peel off, and even when the surplus gas flows out instantaneously, the opening degree of the valve is gradually increased from the peeling part 10B. This makes it possible to promote the gradual increase of the outflow of the surplus gas at the time of opening the valve and to mitigate the shock outflow.

FIG. 3 shows a second embodiment of the present invention. Unlike the above-described embodiment, the valve body is opened by a predetermined pressure of the high-pressure gas jetted into the airbag. A perforation 9H is formed along the shape of the valve body 9 to define the valve body 9 at an appropriate position on the lining 3 of the airbag 1. As shown in FIG. 3A, for example, a circular perforation 9H is formed in the lining 3 of the airbag 1 by forming a circular perforation 9H to define the valve body 9 at an appropriate position.
A minute gap 9B is formed between 9H. The dimension L of the minute gap 9B is set so that a high pressure gas necessary and sufficient for occupant protection is secured in the airbag 1 and ruptures at a predetermined pressure which is reached after the airbag 1 is inflated sufficiently. Is selected.

With this configuration, in the event of a collision, the high-pressure gas generated from the inflator 5 that operates upon detection of deceleration blows into the bag-shaped airbag 1 to inflate the airbag 1 in the event of a collision. When the valve body 9 is deployed, as shown in FIG. 3A, the high pressure gas necessary and sufficient for occupant protection is secured in the airbag 1 and the valve body 9 is inflated until the airbag 1 is fully inflated. Perforations 9 drilled to define
High pressure gas hardly leaks from H, and thus the airbag 1 can be quickly and reliably inflated and deployed.
Thereafter, as shown in FIG. 3 (B), when the airbag 1 is inflated and an internal pressure necessary and sufficient for protecting the occupant is obtained, the internal pressure (black arrow in the drawing) is further increased by excess gas. When the occupant further touches the airbag and the internal pressure of the bag further increases, the minute gap 9B between the perforations 9H and 9H is broken and opened. Thereby, perforation 9H
The valve element 9 defined by
Appears. In other words, the valve body 9 is located at the base 9 other than the perforations.
The valve will be opened with A as a support shaft. At the same time, surplus gas in the airbag 1 is released outside the airbag as indicated by the white arrow. In this manner, the pressure inside the airbag 1 is regulated at the predetermined pressure. At this time, a large number of perforations 9 for defining the valve element 9 are provided.
H has the effect that the valve is broken one by one and the valve opening gradually increases even when the surplus gas flows out instantaneously. Relieve spills.

FIG. 4 shows a third embodiment of the present invention, which is similar to that of the first embodiment. In this embodiment, as shown in FIG. A valve element 9 attached to the outside of the airbag so as to close the vent hole 8 is formed slightly larger than the vent hole 8 and is spotted at a plurality of locations (three locations in the illustrated example) on the main body lining 3 of the airbag 1. It is attached and fixed by a peeling portion 10B such as welding. Therefore, the valve body 9 is opened by the detachment of the valve body 9 due to the peeling of the peeling portion 10B having a relatively weak adhesive force. The attachment of the valve body 9 to the backing 3 is fixed by heat welding such as high frequency welding using the same material that can obtain a relatively strong and uniform adhesive force between the valve body 9 and the backing 3. In the case of joining by bonding, a small welding area is used to reduce the adhesive force of the peeling portion 10B to facilitate peeling, or a different material having a relatively small heat welding force is interposed, though not described in detail. A method of lowering the adhesive force of the peeling portion 10B, that is, the welding force, or the like may be employed.

[0013] With such a configuration, the high pressure gas necessary and sufficient for occupant protection is supplied to the airbag 1.
Until the airbag 1 is fully inflated and inflated,
The vent hole 8 is closed by the presence of the valve body 9 attached to the outside of the vent hole 8, so that the high pressure gas hardly leaks out of the air bag, and the air bag 1 can be quickly and reliably inflated and deployed. . Thereafter, as shown in FIG. 4B, when the airbag 1 is inflated and an internal pressure necessary and sufficient for protecting the occupant is obtained, the internal pressure (black arrow in the drawing) is further increased by excess gas. When the occupant further contacts the airbag and the internal pressure of the bag increases, the valve body 9
The peeled portion 10B, which is a spot welded portion to the lining 3, is peeled off. That is, the valve element 9 falls off and the valve is opened, and excess gas is released from the airbag 2 through the vent hole 8 as indicated by the white arrow. In this manner, the pressure inside the airbag 1 is regulated at the predetermined pressure. In this embodiment, although there is a case where it is not possible to surely reduce the flow of the surplus gas at the time of opening the valve as in the above-described embodiment, it is necessary and sufficient to protect the occupant. After the stage where the internal pressure is obtained, surplus gas can be quickly discharged.

Although the airbag according to the embodiment of the present invention has been described in detail, the airbag device in which the airbag is used is arranged not only in the steering wheel and the passenger seat but also in the door, the rear seat and the like. It is also adopted in an airbag device, and within the scope of the present invention,
The shape and material of the reinforcing member and the valve body of the airbag and the opening for the inflator, the shape and number of the vent holes, the form of fixing such as welding of the valve body to the airbag body, the arrangement of the vent holes, the shape of the peeling portion, the perforation And the like can be appropriately adopted.

[0015]

As described in detail above, according to the present invention, in the event of a collision, high-pressure gas generated from an inflator that operates by detecting deceleration is injected into a bag-shaped airbag. The airbag will be inflated and deployed,
Until the high pressure gas necessary and sufficient for occupant protection is secured in the airbag and the airbag is inflated sufficiently, the vent hole is closed by the presence of the valve element attached to the airbag body, Since the high pressure gas hardly leaks out of the airbag, the airbag can be quickly and reliably inflated and deployed. After that, when the airbag is inflated and the internal pressure necessary and sufficient to protect the occupant is obtained, the internal pressure is further increased by the excess gas, and the occupant contacts the airbag and the internal pressure of the bag further increases. ,
A part of the valve body attached to the airbag main body is peeled off and the valve is opened, and surplus gas flows out of the airbag and the inside of the airbag is regulated at a predetermined pressure. At that time, the peeling portion, which is a part of the attached portion between the valve body and the airbag body, gradually breaks to reach a stage where a sufficient internal pressure for occupant protection has been obtained in the airbag, Even when the surplus gas flows out instantaneously, the opening degree of the valve gradually increases, and the flow of the surplus gas at the time of opening the valve can be gradually increased to mitigate the shocking outflow. Thus, according to the present invention, since no excessive gas is required for inflating the airbag, the capacity of the inflator can be reduced and the module can be made compact, so that the module itself can be made lightweight and compact.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of the present invention.
(A) is a cross-sectional view of a half of the airbag device, and FIG.
FIG. 1B is a bottom view of the vent hole as viewed in the direction of the arrow A, and FIG. 1C is a perspective view of the A showing operation of the vent hole.

FIG. 2 shows a first embodiment of the present invention, and FIG.
FIG. 2A is an overall perspective view of a partially cut airbag device from which an inflator is omitted, and FIG.

FIG. 3 shows a second embodiment of the present invention.
3A is a bottom view of the vent hole, and FIG. 3B is a perspective view showing the operation of the vent hole.

FIG. 4 shows a third embodiment of the present invention.
4A is a bottom view of the vent hole, and FIG. 4B is a perspective view showing the operation of the vent hole.

FIG. 5 is an overall perspective view and a bottom view of a partial cut of a conventional airbag device.

[Explanation of symbols]

 Reference Signs List 1 airbag 2 (occupant side) outer material 3 (vehicle side) lining 4 opening for inflator 5 inflator 6 reinforcing body 7 retainer 8 vent hole 9 valve body 9A root 9B minute gap 9H perforation 10A welding part 10B peeling part 12 base plate

Claims (2)

[Claims] 1. A bag-shaped airbag in which an inflator is mounted in an opening for an inflator formed substantially in the center, a vent hole is formed at an appropriate position of the airbag, and a valve is provided so as to close the vent hole. The valve body is attached, and a part of the attached portion of the valve body is peeled off by the action of a predetermined airbag internal pressure at the time of the airbag deployment operation, so that the valve body is opened. Airbag. 2. A bag-shaped airbag in which an inflator is mounted in an inflator opening formed substantially in the center, and a perforation is formed along a shape of the valve body so as to define a valve body at an appropriate position of the airbag. An airbag characterized in that the perforation is opened and the valve element is opened by the action of a predetermined airbag internal pressure when the airbag is deployed.