JP2001277991A - Air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag for opening a part of a vent hole and closing a great part in the initial stage of inflation and increasing an opening quantity of the vent hole when internal pressure of an air bag becomes prescribed pressure or more. SOLUTION: This air bag 1 has the almost semicircular vent hole 5 and an almost semicircular cover 6 for covering this vent hole 5. The cover 6 is arranged along an inside surface of the air bag 1. An arc part of the vent hole 5 and an arc part of the cover 6 are joined by a joining means such as a sewing thread 7. A chord part of the vent hole 5 and a chord part of the cover 6 overlap each other by non-bonding. A communicating part 6c is arranged in the cover 6. The vent hole 5 is closed in a great part by the cover 6 in the initial stage of inflation of the air bag, and a part is opened by the communicating part 6c. When the internal pressure of the air bag becomes prescribed pressure or more, a non-bonding part of the cover 6 protrudes outside the vent hole 5 to increase the opening quantity of the vent hole 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag provided in an automobile or the like, and more particularly, to an airbag having a vent hole through which gas inside flows out.

[0002]

2. Description of the Related Art As is well known, an airbag device for a vehicle is configured to supply gas into the airbag at the time of collision of the vehicle and to rapidly deploy the airbag.

A vent hole is provided in the airbag to reduce the impact applied to the airbag by allowing gas in the airbag to flow out of the airbag when an occupant enters the deployed airbag. ing.

If the gas flows out of the vent hole during the initial stage of deployment of the airbag, the output of the gas generator (inflator) must be increased accordingly. In view of this, a configuration has been considered in which a rubber or resin film is attached to the vent hole, and the film is broken when the internal pressure of the airbag exceeds a predetermined value.

[0005] Further, a slit is formed in the base fabric of the airbag, and a film is adhered to the airbag so as to cover the slit. There is something that is open.

[0006] Further, there is a method in which a vent hole of an airbag is closed by sewing with a thread, and when the internal pressure of the airbag becomes higher than a predetermined value, the thread is cut and the vent hole is opened.

[0007]

In any of these conventional airbags, it is necessary to select a film or a thread which does not break at the beginning of the deployment of the airbag.
In addition, since films and yarns require stable breaking strength, expensive materials had to be selected. That is,
When the airbag is deployed, a pulling force is applied to the base fabric of the airbag in the deployment direction. Since this force acts as a tension on the film or yarn, the film or yarn needs to withstand this tension. If the breakage of the film or yarn occurs earlier, the vent hole opens earlier than the predetermined timing, and if the breakage of the film or yarn delays, the vent hole opens later than the predetermined timing.

Further, when the vent hole is completely closed by a film or a thread and the airbag is sealed, the airbag is folded at an early stage of the inflation of the airbag, and the cloth materials constituting the airbag are joined together. Are in close contact with each other, it is difficult for the closely adhered cloth materials to separate from each other only by supplying the gas from the inflator.
The deployment of the airbag may be delayed.

The present invention solves the above-mentioned conventional problems. In the initial stage of the inflation of the airbag, a part of the vent hole is opened and most of the vent hole is closed, and when the internal pressure of the airbag exceeds a predetermined pressure, the vent hole is opened. An object of the present invention is to provide an airbag in which a hole is reliably opened to a required area.

[0010]

An airbag according to the present invention comprises:
In an airbag having a vent hole for letting out gas inside the airbag, a cover that opens a part of the vent hole and closes most of the vent hole is provided,
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, a part of the cover protrudes outside the vent hole due to gas pressure,
Thereby, the opening amount of the vent hole is increased.

According to the airbag of the present invention, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, the vent hole is partially opened and mostly closed by the cover. Thereby, even when the airbag is folded and the cloth materials constituting the airbag are in close contact with each other in the initial stage of the inflation of the airbag immediately after the inflator starts operating, The inside and outside communicate with each other, and the outside air is introduced from a part of the vent hole with the inflation of the airbag, so that the closely adhered cloth materials are easily separated from each other, and the airbag is quickly opened. Start to deploy to. Further, since a large amount of gas generated from the inflator does not flow out of the vent hole, the airbag expands rapidly. When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover protrudes to the outside of the vent hole due to the pressing force of the gas, thereby increasing the opening amount of the vent hole. The majority means about 80 to 99.8% of the opening area of the vent hole.

The airbag may be provided with a communication portion that constantly communicates the inside and outside of the airbag with the cover, and a part of the vent hole is opened by the communication portion.
Further, a part of the edge of the cover is separated from the edge of the vent hole toward the inside of the vent hole, so that a part of the vent hole can be opened.

In the airbag of the present invention, a part of the periphery of the vent hole of the airbag is connected to the cover, and the other part of the periphery of the vent hole is not connected to the cover.
It is preferable that the opening amount of the vent hole be increased by at least the non-joined portion protruding outside the airbag.

With such a configuration, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, the vent hole is partially opened and mostly closed by the cover.
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the non-joined portion of the cover protrudes out of the vent hole, and the opening amount of the vent hole is reliably increased.

In another aspect of the airbag of the present invention, in an airbag having a vent hole for letting out gas inside the airbag, a cover for covering the vent hole is provided, and the cover has an exhaust port. And a small hole are provided, the small hole always communicates with the inside and outside of the airbag, and the exhaust port is covered by the vent hole peripheral portion of the airbag until the internal pressure of the airbag becomes a predetermined pressure or more. It is exposed when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure.

According to this aspect, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, a part of the vent hole is opened by the small hole provided in the cover, and most of the vent hole is closed by the cover. When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover is pushed out from the vent hole by the pressing force of the gas, and the exhaust port is exposed, so that the amount of gas flowing out through the vent hole and the exhaust port is reliably increased. On this occasion,
The exposed area of the cover pushed out from the vent hole is almost proportional to the magnitude of the airbag internal pressure. For this reason, particularly when the exhaust port is formed in a long hole shape or a porous shape extending in a direction away from the opening of the vent hole, the cover has an opening area (hereinafter, referred to as an area) exposed from the vent hole peripheral edge of the exhaust port. , May be simply referred to as the “opening degree of the exhaust port”.)
Can be appropriately and automatically changed in accordance with the magnitude of the airbag internal pressure to control the outflow amount of gas flowing out of the vent hole and the exhaust port. Also,
When the gas flows out and the internal pressure of the airbag falls below a predetermined pressure, the cover returns to the initial state of the inflation of the airbag due to the reduced pressing force of the gas, and the exhaust port is again opened to the vent hole of the airbag. By being covered by the peripheral portion, the outflow of gas is reduced. Thus, it is possible to prevent the gas from flowing out of the vent hole and the exhaust port more than necessary and reduce the impact absorbing power of the airbag.

In this aspect, the vent hole is formed in a slit shape having a predetermined opening width. When the internal pressure of the airbag becomes higher than the predetermined internal pressure, the slit is pushed open to expose the exhaust port. You may comprise.

With this configuration, when the internal pressure of the airbag is equal to or lower than a predetermined pressure, most of the slit is closed by the cover and a small hole is exposed from the opening to partially open the vent hole. The mouth is securely closed by being covered by the slit periphery of the airbag of the airbag. When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover pushes the slit open to expose the exhaust port, and reliably increases the outflow of gas through the exhaust port. Also, when the internal pressure of the airbag falls below a predetermined pressure due to the outflow of gas, the cover returns to its original state, and the slit pushed and opened by the cover is restored. Prevent outflow of gas. Further, since the vent hole is formed in a slit shape, a member having a small surface area can be used for the cover.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a perspective view from the rear of an airbag according to an embodiment of the present invention, FIG. 2 is an exploded perspective view showing an attached state of a cover, FIG. 3 is a plan view of a vent hole portion of the airbag, FIG. 4 is a sectional view taken along the line IV-IV of FIG. 3 and an explanatory view showing an aspect of the cover in the process of inflating the airbag in this section, and FIG. 5 is a perspective view showing an open state of a vent hole portion.

The airbag 1 has an opening 2 at a rear portion thereof for receiving gas from an inflator (not shown). This airbag 1 is made of cloth and has an opening 2.
A plurality of bolts or rivets through holes 4 are provided in the peripheral portion 3 of the airbag 1, and the airbag 1 can be connected to a container (not shown) of the airbag device by the bolts or rivets.

A substantially semicircular vent hole 5 is provided on the rear surface of the airbag 1. In a state before the airbag 1 is inflated (that is, a state in which the airbag 1 is folded and stored in a container) and in a state where the airbag internal pressure at the initial stage of inflation is equal to or lower than a predetermined pressure, the vent hole 5 is Covered. The cover 6 is made of a cloth or a resin sheet having a substantially similar shape to the vent hole 5 and having a surface area of a substantially semicircular shape overlapping the vent hole 5 larger than that of the vent hole. The cover 6 is provided with a hole-shaped communication portion 6c that communicates the inside and outside of the airbag. The communication portion 6c allows the cover 6 to open a part of the vent hole 5 and close most of the vent hole 5. Here, "most" means about 80 to 99.8% of the opening area of the vent hole.

As shown in FIG. 3, the vent hole 5 has an arc portion 5a and a chord portion 5b. Also, cover 6
Has an arc-shaped portion 6a and a chord-shaped portion 6b. Communication part 6c
Are provided at positions not covered by the peripheral edge of the vent hole of the cover 6.

The cover 6 is arranged along the inner surface of the airbag 1 such that the arc-shaped portion 6a and the chord-shaped portion 6b of the surface overlap the peripheral portions of the arc-shaped portion 5a and the chord-shaped portion 5b of the vent hole 5, respectively. The overlapping portion of the arc-shaped portion 6a of the cover 6 and the arc-shaped portion 5a of the vent hole 5 is joined by a joining means such as sewing thread 7 or bonding or welding, and the chord-shaped portion 6b of the cover 6 is It is overlapped with the periphery of the chord-shaped portion 5b of the vent hole 5 in a non-joined state (hereinafter, referred to as a "bead").
A portion of the cover 6 that overlaps with the vent hole 5 in a non-bonded manner may be referred to as a non-bonded portion. ).

The cover 6 closes most of the vent hole 5 when the internal pressure of the airbag is equal to or lower than a predetermined pressure when the airbag is inflated. As shown in FIG. 4, the portion of the cover 6 which is deformed and overlaps with the opening of the vent hole 5 is pushed out of the vent hole 5 and the uncoupled portion of the cover 6 moves toward the opening edge of the vent hole 5. Then, it protrudes outside the vent hole 5 to increase the opening amount of the vent hole.

In the airbag 1, a peripheral portion 3 is connected to a container by bolts or the like. The airbag 1 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. In the event of an automobile collision or the like, the inflator performs gas ejection operation, the airbag starts to inflate, the lid opens, and the airbag deploys in the vehicle compartment.

The airbag 1 is developed into a shape shown in FIG. 1 by gas from an inflator introduced into the inside through the opening 2.

Although not shown, in the initial stage of inflation of the airbag immediately after the start of operation of the inflator, the airbag 1 is folded, and the cloth materials constituting the airbag 1 are in close contact with each other. It has become. At this time, the inside and the outside of the airbag 1 are communicated by the communication portion 6c, and the outside air is introduced from the communication portion 6c with the inflation of the airbag 1, so that the closely adhered cloth materials are connected to each other. Are easily separated from each other, and the airbag 1 starts to deploy quickly.

Thereafter, when the internal pressure of the airbag is lower than a predetermined pressure, the vent hole 5 is mostly closed by the cover 6, and a large amount of gas generated from the inflator does not flow out from the vent hole 5. The bag 1 expands rapidly. When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 6 is deformed by the pressing force of the gas.
Extruded toward the outside. As a result, the opening amount of the vent hole 5 increases, and excess gas inside the airbag flows out. Thus, when the occupant enters the airbag 1, excess gas in the airbag 1 flows out through the vent hole 5 to the outside, so that the impact applied to the occupant is absorbed. Become.

Here, in general, a plain woven cloth composed of warps and wefts is often used for the airbag as a cloth material constituting the airbag. By forming the chordal portion 5b of the vent hole 5 so as to extend along the weave of the cloth material of the airbag 1, the vent hole 5 is greatly deformed by the tension at the time of inflation of the airbag, The formation of the holes 5 can prevent the strength of the airbag 1 from being significantly reduced.

On the other hand, the cover 6 may be made of the same material as the airbag 1 or may be different. However, when the cover 6 is deformed by a gas pressure higher than a predetermined pressure, the non-joined portion of the cover 6 becomes In order for the cover 6 to protrude outside the vent hole 5 smoothly, it is desirable that the cover 6 has a relatively high elasticity with respect to the periphery of the vent hole of the airbag 1. Therefore, for example, in the case where the cover 6 is made of the same cloth material as the airbag 1 in this embodiment, the weave of the cloth material of the cover 6 is in the extending direction of the chordal portion 6b of the cover 6. The cover 6 is configured to extend and contract relatively easily in the direction in which the chord-shaped portion extends and in a direction perpendicular to the extending direction. The angle at which the weave of the cloth material of the cover 6 obliquely extends with respect to the extending direction of the chord-shaped portion 6b is preferably about 30 ° to 60 °.

In this embodiment, the opening of the vent hole 5 and the cover 6 are formed in a substantially semicircular shape, but the present invention is not limited to this. The opening of the vent hole 5 may be formed in another shape such as a circular shape, a triangular shape, a long hole shape, or a plurality of openings as long as the strength of the airbag 1 is not impaired. Good. A reinforcing cloth (not shown) may be provided around the vent hole 5 by stitching or bonding, and a reinforcing stitch (a seam (not shown) provided so as to surround the vent hole) is applied. You may. The cover 6 may be formed in a rectangular shape or another shape that covers the vent hole 5, a part of the cover 6 may be coupled to the vent hole peripheral edge of the airbag, and the other part may be uncoupled to the vent hole peripheral edge. . Also in this case, it is desirable that the cover 6 has relatively high elasticity with respect to the airbag 1. Hereinafter, an airbag provided with such a vent hole and a cover will be specifically described with reference to FIGS.

FIG. 6 is an explanatory view showing an open state of a vent hole portion of an airbag according to another embodiment.

As shown in FIG. 6 (a), the airbag 10 is provided with a vent hole 15 having a long hole shape. Although not shown, the airbag 10 has the same configuration as the airbag 1 described above, and has an opening for receiving gas from the inflator at a rear portion thereof. The airbag 10 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening. The bolts or rivets allow the airbag 10 to be inserted into a container of the airbag device. It is possible to connect.

The vent hole 15 is provided on the rear surface of the airbag 10. A state before the airbag 10 is inflated (that is, a state in which the airbag 10 is folded and stored in a container).
When the internal pressure of the airbag is equal to or lower than a predetermined pressure in the initial stage of inflation, the vent hole 15
are covered by a cover 16 having a. The vent hole 15 is provided in order to prevent the vent hole 15 from being greatly deformed by the tension at the time of inflation of the airbag, and the strength of the airbag 10 from being significantly reduced due to the provision of the vent hole 15. The long axis of the elongated opening is formed so as to extend along the radial weave of the cloth material constituting the airbag 10.

The cover 16 has a band shape extending along the longitudinal direction of the vent hole 15 and covers the vent hole 15 from the inside of the airbag 10 so as to overlap the peripheral edge of the vent hole 15. Both short-side edges of the cover 16 are arranged near the peripheral edges on both ends of the vent hole 15 of the airbag 10, and are overlapped with the vent holes 15 of the airbag 10 overlapping with each other by a joining means such as a sewing thread 17 or bonding or welding. It is connected near the periphery. Both edges on the long side of the cover 16 extend along the long edge of the vent hole 15 and are arranged so as to overlap with the long edge of the vent hole 15 in a non-bonded manner. (Hereinafter, both edges on the long side of the cover 16 may be referred to as non-joined portions.) The communication portion 16 a is provided at a position that is not covered by the peripheral portion of the vent hole 15 of the cover 16.

When the airbag internal pressure is equal to or lower than a predetermined pressure at the time of inflation of the airbag, the cover 16 is connected to the vent hole 1 through the communication portion 16a.
5 is partially opened and most of the airbag 5 is closed, and when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the airbag is deformed by the pressing force, and the portion overlapping the opening of the vent hole 15 is pushed out from the vent hole 15. The non-joined portion of the cover 16 moves toward the opening edge of the vent hole 15 and protrudes outside the vent hole 15 to be bent.
5 is increased. Here, “most” refers to 80% of the opening area of the vent hole.
About 99.8%.

When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 16 is smoothly deformed by the pressing force of the gas so that the non-joined portion of the cover 16 protrudes from the vent hole 15. Has relatively high elasticity with respect to the airbag 10. For example, when the cover 16 is made of the same cloth material as the airbag 10, the cover 16 is formed such that the weave of the cloth material of the cover 16 is inclined with respect to the extending direction of the long side edge of the cover 16. It is configured to intersect. As a result, the cover 16 becomes relatively easy to expand and contract in its long side direction and in a direction perpendicular to the long side, and when the internal pressure of the airbag exceeds a predetermined pressure, the cover 16 is surely deformed and the vent hole 15 It can protrude and vent hole 15 can be opened. The angle at which the weave of the cloth material of the cover 16 obliquely intersects with the extending direction of the long side edge is preferably about 30 ° to 60 °.

In the airbag 10, the peripheral edge of the rear opening is connected to the container by bolts or the like. And this airbag 10 is folded and accommodated in a container,
A lid is attached to this container. The container is provided with an inflator. In the event of a car collision, etc., the inflator operates to eject gas, and the airbag starts inflating.
The lid opens and the airbag deploys in the vehicle cabin.

The airbag 10 is developed into a shape similar to that of the airbag 1 shown in FIG. 1 by gas from an inflator introduced through the opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts operating, the airbag 10 is folded,
Are in close contact with each other. At this time, the inside and the outside of the airbag 10 are communicated with each other by the communication portion 16a, and the outside air is introduced from the communication portion 16a as the airbag 10 inflates, so that the closely adhered cloth materials are connected to each other. Are easily separated from each other, and the airbag 10 starts to deploy quickly.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, the vent hole 15 is mostly covered with the cover 16.
The airbag 10 is inflated rapidly because a large amount of gas generated from the inflator does not flow out of the vent hole 15. When the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, the cover 16 is deformed by the pressing force of the gas, and the non-joined portion of the cover 16 is pushed out of the vent hole 15. As a result, the opening amount of the vent hole 15 increases, and excess gas inside the airbag flows out. Thereby, when the occupant enters the airbag 10, the airbag 10
Excess gas inside flows out to the outside through the vent hole 15, and the impact applied to the occupant is absorbed.

FIG. 7 is an explanatory view showing an open state of a vent hole portion of an airbag according to still another embodiment.

As shown in FIG. 7 (a), the airbag 20 is provided with two continuous vent holes 25 and 26. Although not shown, the airbag 20
Has a configuration similar to that of the airbag 1, and has an opening at its rear portion for receiving gas from the inflator. Further, the airbag 20 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening, so that the airbag 20 is attached to the container of the airbag device by the bolts or rivets. It is possible to connect.

The vent holes 25, 26 are provided in the airbag 20.
It is provided on the rear surface. In a state before the airbag 20 is inflated (that is, a state in which the airbag 20 is folded and stored in a container) and in a state where the internal pressure of the airbag at the initial stage of inflation is equal to or lower than a predetermined pressure, both of the vent holes 25 and 26 It is covered by a cover 27 made of a single cloth or a resin sheet. The cover 27 is provided with communication portions 27a and 27b formed of through holes.

Each of the vent holes 25 and 26 has a substantially semicircular opening shape, and chord-shaped edges 25b and 26b are provided at the edges on the side away from each other. The edges 25b and 26b of these vent holes 25 and 26 (hereinafter, may be simply referred to as "chords 25b" and "chords 26b", respectively) are parallel to each other. Further, these chordal portions 25b and 26b are both provided in parallel along the weave of the airbag 20, so that the tension at the time of inflation of the airbag causes the vent hole 2b to be bent.
The opening areas of the vent holes 25 and 26 are prevented from greatly changing due to the extension of the holes 5 and 26.

The cover 27 is a single band that covers the vent holes 25, 26 along the inner surface of the airbag 20, and both long edges of the cover 27 have the vent holes 25, 26.
And the vent hole 26 are arranged so as to overlap near the periphery of the vent holes 25 and 26 along a continuous direction, and the airbag 2 is connected by sewing means 28 or bonding means such as adhesion or welding.
Tied to 0. Both edges on the short side of the cover 27 are chordal portions 25b and 26b of the vent holes 25 and 26, respectively.
(Hereinafter, both edges on the short side of the cover 27 may be referred to as “non-joined portions”). The communication portions 27a and 27b are connected to the vent holes 25,
26 is provided at a position not covered by the peripheral portion.

The cover 27 opens a part of the vent holes 25 and 26 through the communicating portions 27a and 27b when the internal pressure of the airbag is lower than a predetermined pressure when the airbag is inflated, similarly to the cover 6 described above. Close most of the
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the airbag is deformed by the pressing force, the portion overlapping with the openings of the vent holes 25 and 26 is pushed out from the vent holes 25 and 26, and the non-joined portion of the cover 27 is connected to the vent hole 2.
Vent hole 2 moves toward the opening edge of 5, 26
The vent holes 25, 26 protrude outside the vent holes 25, 26 to increase the opening amount. Here, “most” refers to 80 to 9 of the opening area of the vent hole.
It means about 9.8%.

When the internal pressure of the air bag becomes equal to or higher than a predetermined pressure, the cover 27 is smoothly deformed by the pressing force of the gas.
The cover 27 has a relatively high elasticity with respect to the airbag 20 so as to protrude from the airbag 26. For example, when the cover 27 is made of the same cloth material as the airbag 20, the cover 27 is formed such that the weave of the cloth material of the cover 27 is oblique to the extending direction of the short side edge of the cover 27. It is configured to As a result, the cover 27 relatively easily expands and contracts in the short side direction and the direction orthogonal to the short side, and when the internal pressure of the airbag becomes a predetermined pressure or more, the cover 27 is surely deformed and the vent hole 2
The vent holes 25 and 26 can protrude from the holes 5 and 26 and be opened. The angle at which the weave of the cloth material of the cover 27 is oblique to the extending direction of the short side edge is 30 ° to 60 °.
The degree is preferred.

The airbag 20 has a rear opening peripheral edge connected to a container by bolts or the like. And this airbag 20 is folded and accommodated in a container,
A lid is attached to this container. The container is provided with an inflator. In the event of a car collision, etc., the inflator operates to eject gas, and the airbag starts inflating.
The lid opens and the airbag deploys in the vehicle cabin.

The airbag 20 is developed into a shape similar to that of the airbag 1 shown in FIG. 1 by gas from an inflator introduced into the inside through a rear opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts operating, the airbag 20 is folded,
Are in close contact with each other. At this time, the inside and the outside of the airbag 20 communicate with each other through the communication portions 27a and 27b, and the airbag 20 is brought into close contact with the airbag 20 by the introduction of outside air from the communication portions 27a and 27b as the airbag 20 inflates. The separated fabric materials are easily separated from each other, and the airbag 20 starts to deploy quickly.

Thereafter, when the internal pressure of the airbag is lower than the predetermined pressure, most of the vent holes 25 and 26 are closed by the cover 27, and a large amount of gas generated from the inflator flows out of the vent holes 25 and 26. As a result, the airbag 20 inflates rapidly. When the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, the cover 27 is deformed by the pressing force of the gas, and the non-joined portion of the cover 27 is pushed out of the vent hole 27. As a result, the amount of opening of the vent holes 25 and 26 increases, and excess gas inside the airbag flows out. Accordingly, when the occupant enters the airbag 20, excess gas in the airbag 20 flows out through the vent holes 25 and 26, and the impact applied to the occupant is absorbed. Become like

In the airbag 20, the vent hole is formed as two continuous substantially semicircular openings. However, the vent hole is formed within a range that does not impair the strength of the air bag. The shape and number are not limited to this, and may have a circular or other shape.
More than one continuous opening may be used. The cover may be configured to cover a plurality of vent holes with a single cover, or may be configured to cover the vent holes with separate covers.

Next, still another embodiment of the present invention will be described with reference to FIGS. Fig. 8 is a perspective view showing an airbag according to another embodiment, Fig. 9 is an exploded perspective view showing an attached state of a cover, and Fig. 10 shows a slit portion when the airbag internal pressure is equal to or lower than a predetermined pressure. FIG. 11 is an explanatory view showing a slit portion when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, and FIG. 12 is a perspective view of the slit portion in a state where an exhaust port is exposed.

The airbag 50 has an opening 5 at its rear portion for receiving gas from an inflator (not shown).
2 This airbag 50 is made of cloth,
A plurality of bolts or rivets insertion holes 54 are provided in a peripheral portion 53 of the opening 52, and the airbag 50 can be connected to a container (not shown) of the airbag device by these bolts or rivets. .

A slit 55 is provided on a rear surface of the airbag 50. The slit 55 is covered with a cover 56 made of a cloth or a resin sheet when the airbag 50 is in a state before inflation (that is, when the airbag 50 is folded and stored in a container) and when the airbag internal pressure is equal to or lower than a predetermined pressure. ing. The airbag 50 has a circular shape, and the fabric material of the airbag 50 is a plain-woven cloth, like the airbag 1. The slit 55 is provided along the texture of the airbag 50. This makes it difficult for the length of the slit 55 to change when the airbag is inflated.

The slit 55 is, as shown in FIG.
It is formed in a slender, substantially elongated hole shape having a width slightly larger than the diameter of a communication portion 56a described later.

The cover 56 is a belt-like member extending along the cleavage direction of the slit 55, and covers the slit 55 from the inside of the airbag 50 so as to overlap with the peripheral edge of the slit 55. The edges on both ends of the cover 56 are arranged so as to overlap with the vicinity of the peripheral edges on both ends of the slit 55, and the sewing thread 57.
It is connected to the airbag 50 by connecting means such as bonding, welding, and the like. The other portion of the cover 56 is not connected to the airbag 50 and overlaps near the periphery of the slit 55 (hereinafter, such a portion may be referred to as a non-connected portion). The non-joined portion of the cover 56 is provided with a circular exhaust port 58 at a portion overlapping with the peripheral edge of the slit 55 of the airbag 50 and covered by the airbag 50. At a substantially central portion of the cover 56, a small hole-shaped communicating portion 56 a communicating between the inside and the outside of the airbag 50 is provided at a position not covered by the peripheral portion of the slit 55.

When the internal pressure of the airbag is equal to or lower than a predetermined pressure when the airbag is inflated, the cover 56 communicates with the communication portion 5.
6a, a part of the slit 55 is opened, and the exhaust port 58 is opened.
Is covered by the peripheral portion of the slit 55 of the airbag 50, and when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the non-joined portion of the cover 56 is deformed by the pressing force, thereby pushing the slit 55 open and opening the exhaust port. 58 are exposed. The opening degree of the exhaust port 58 (the opening area of the opening formed by the peripheral portion of the slit 55 and the peripheral portion of the exhaust port 58 exposed from the peripheral portion of the slit 55) depends on the internal pressure of the airbag. It changes automatically in response to this.

In the airbag 50, a vent hole is formed by the openings provided in the slit 55 and the cover 56. With this configuration, the vent hole is partially opened and largely closed by the cover 56 when the airbag internal pressure is equal to or lower than a predetermined pressure, and is closed when the airbag internal pressure is equal to or higher than the predetermined pressure. It is opened according to the bag internal pressure. Here, “most” means about 80 to 99.8% of the opening area when the opening of each opening of the vent hole is fully opened.

When the internal pressure of the air bag becomes equal to or higher than a predetermined pressure, the non-joined portion of the cover 56 is deformed by the pressing force of the gas, and the slit 55 is pushed open, and the exhaust port 58 is opened.
The cover 56 is preferably configured to have relatively high elasticity with respect to the airbag 50 so that the airbag 50 is exposed. This cover 56 is used for the airbag 5.
The airbag 50 may be made of the same cloth material as that of the airbag 50, or may be made of a different material. By forming the cover 56 so as to be oblique to the extending direction of the edge in the vertical direction, the cover 56 becomes relatively easy to expand and contract in the length direction and the width direction. When this happens, the cover 56 is surely deformed and pushes the slit 55 open, so that the exhaust port 58 can be exposed. The angle at which the weave of the cloth material of the cover 56 is oblique to the extending direction of the edge in the length direction is 30 ° to 60 °.
° is preferable.

In the airbag 50, a peripheral portion 53 is connected to a container by bolts or the like. The airbag 50 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. In the event of an automobile collision or the like, the inflator performs gas ejection operation, the airbag starts to inflate, the lid opens, and the airbag deploys in the vehicle compartment.

The airbag 50 is activated by the gas from the inflator introduced through the opening 52 into the airbag 50.
It is developed into a circle as shown in the figure.

Although not shown, in the initial stage of inflation of the airbag immediately after the start of operation of the inflator, the airbag 50 is folded and this airbag 50 is folded.
Are in close contact with each other. At this time, the inside and the outside of the airbag 50 are communicated by the communication portion 56a, and the outside air is introduced from the communication portion 56a with the inflation of the airbag 50, so that the closely adhered cloth materials are connected to each other. Are easily separated from each other, and the airbag 50 starts to deploy quickly.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, most of the slit 55 is closed by the cover 56, and a large amount of gas generated from the inflator does not flow out of the vent hole 55. 50 expands rapidly. Then, when the internal pressure of the airbag becomes equal to or higher than the predetermined internal pressure, the cover 56 is deformed by the pressing force of the gas, and pushes the slit 55 open to expose the exhaust port 58. As a result, the gas flows out from the exhaust port 58 and lowers the internal pressure of the airbag. Thereafter, when the internal pressure of the airbag decreases to a predetermined pressure or less,
The cover 56 is restored to the initial state due to the reduced pressure of the gas, and accordingly, the slit 55 pushed and opened by the cover 56 is restored to the original state and the exhaust port 55 is covered. Reduce gas outflow. As a result, the airbag internal pressure is maintained at a substantially predetermined pressure, and even when the occupant enters the airbag 50, the airbag 50 reliably receives the occupant and absorbs the impact.

In this embodiment, the cover 56 is provided with a circular exhaust port 58, but the shape of the exhaust port is not limited to this.
6 may be provided with a long hole-shaped exhaust port 60 having a long axis extending in a direction orthogonal to the cleavage direction of the slit 55 as shown in FIG. 13, and as shown in FIG. A porous exhaust port 62 that extends in a direction orthogonal to the cleavage direction of 55 may be provided. As shown in FIGS. 15 and 16, one of the vertices is disposed near the slit 55, and an exhaust port 64 having a substantially triangular shape that widens in the extending direction of the slit 55 as the distance from the slit 55 increases. You may.

As described above, the slit 55 is provided on the cover 56.
When the exhaust ports 60, 62, 64 having opening shapes deflected in a direction orthogonal to the cleavage direction of the
As shown in the figure, since the exhaust ports 60, 62, and 64 are automatically exposed at an appropriate opening in accordance with the level of the internal pressure of the airbag, the gas can flow out without excess or deficiency. The internal pressure of the airbag can be maintained at an appropriate pressure in response to a change in the internal pressure of the airbag.

As shown in FIGS. 15 and 16, a reinforcing cloth 65 may be provided on the peripheral edge of the slit 55 of the airbag 50, whereby the peripheral edge of the slit 55 is reinforced and the airbag is inflated. The airbag 50 can be more reliably prevented from being damaged at the time or when the slit 55 is expanded by the cover 56.

In FIGS. 15 and 16, this reinforcing cloth 65 is used.
Is sewn on the peripheral edge of the slit 55 together with the cover 56 by a sewing thread 57 and is connected to the airbag 50 by a sewing thread 66 so as to surround the slit 55 in the vicinity of the slit 55. However, the present invention is not limited to this, and the reinforcing cloth 65 may be independently provided on the airbag 50 by means such as sewing or bonding. Although not shown, the reinforcing cloth 6
Instead of 5, the periphery of the slit 55 may be reinforced by so-called reinforcing stitching in which a seam is provided so as to surround the slit 55.

In this embodiment, the slit 55 is formed by an elongated substantially elongated hole having a width slightly larger than the diameter of the communicating portion 56a. By exposing the communicating portion 56a from the portion, the inside and outside of the airbag 50 are always communicated, but the configuration of the slit 55 is not limited to this. For example, as shown in FIG. 36, the slit 55 has a cut shape, and a large-diameter portion having a circular opening shape near the center of the slit 55 and having an opening diameter slightly larger than the communication portion 56a. A configuration may be adopted in which the airbag 50 is provided with the communication portion 56a exposed from the slit 55 via the large-diameter portion 55a so that the inside and outside of the airbag 50 are always communicated.

In the airbag 50 thus configured, the slit 55, the large diameter portion 55a, and the cover 56
Vent holes (not shown)
Is formed.

When the airbag internal pressure is equal to or lower than a predetermined pressure at the time of inflation of the airbag, the cover 56 has a large diameter portion 55a.
The communication portion 56a is exposed through the opening, and the exhaust port 58 is covered by the peripheral edge of the slit 55 of the airbag 50,
As a result, a part of the vent hole is opened and most of the vent hole is closed. When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 5 is pressed by the pressing force.
The non-joined portion 6 is deformed to push the slit 55 open, exposing the exhaust port 58 and opening the vent hole. The opening degree of the exhaust port 58 automatically changes according to the airbag internal pressure. Thus, even in the case of such a configuration, the airbag 50 can achieve the same effect as the above-described configuration.

As shown in FIG. 37, the slits provided in the airbag 50 may be two slits 67 and 68 intermittently extending on the same axis.
In this case, these slits 67,
A circular opening 69 having a diameter slightly larger than the diameter of the communicating portion 56a is provided in a portion between the openings 68.
The communication portion 56a is exposed through the airbag, and is configured to always communicate between the inside and the outside of the airbag 50. At this time, the portion of the airbag 50 between the opening 69 and each of the slits 67 and 68 breaks when the internal pressure of the airbag exceeds a predetermined pressure.

In this case, the airbag 5
0 denotes the slits 67 and 68, the opening 69, and the cover 5
A vent hole (not shown) is formed by each opening provided in 6.

When the internal pressure of the airbag is equal to or lower than a predetermined pressure when the airbag is inflated, the cover 56 opens.
a is exposed through the opening 69 to communicate the inside and the outside of the airbag, and the exhaust port 58 is covered by the slits 67 and 68 of the airbag 50 and the peripheral edge of the opening 69, thereby forming one of the vent holes. The part is open and largely closed. At this time, the portion between the opening 69 of the airbag 50 and each of the slits 67 and 68 is not broken by the pressing force of the gas from the cover 56 and the inflator, and each edge of the slits 67 and 68 is pushed by the cover 56. Because it is prevented from being opened,
When the internal pressure of the airbag is equal to or lower than a predetermined pressure, the exhaust port 68 is not reliably exposed.

When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the non-joined portion of the cover 56 is deformed by the gas pressure to press the peripheral edge of the opening 69. With this pressing force, the opening 69 of the airbag 50 and the slits 67, 6
8 and the slit 67 and the slit 68
And the cover 56 can easily connect these slits 6
7 and 68 are pushed open to expose the exhaust port 58 to open the vent hole. At this time, the degree of opening of the exhaust port 58 exposed automatically changes according to the internal pressure of the airbag.

In the airbag 50 configured as described above, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, it is possible to more reliably maintain a state in which a part of the vent hole is opened and most of the vent hole is closed. When the internal pressure of the airbag exceeds a predetermined pressure, the airbag 5
The portion between the zero opening 69 and each of the slits 67 and 68 is broken to easily expose the exhaust port 58, thereby achieving the same effect as the above-described configuration.

Further, in this embodiment, an exhaust port 58 is provided in the cover 56, and when the internal pressure of the airbag exceeds a predetermined pressure, the cover 56 pushes the slit 55 open to expose the exhaust port 58. However, the exhaust port 58 may be omitted. In this case, after the cover 56 is pushed and opened, the non-joined portion of the cover 56 protrudes from the slit 55, With the slit 55 pushed and opened, the slit 55 can be opened to allow gas to flow out, and the same effects as in the above-described embodiment can be obtained.

In the above-described embodiment, the cover is provided with a hole-shaped communicating portion that constantly communicates the inside and the outside of the airbag, and a part of the vent hole is opened by the communicating portion. Is not limited to this,
For example, a configuration may be adopted in which a part of the edge of the cover is separated from the edge of the vent hole to the inside of the vent hole, so that a part of the vent hole is opened.

Referring to FIGS. 17 to 35, still another embodiment of the present invention will be specifically described with reference to examples. FIG. 17 is an exploded perspective view of a vent hole portion of an airbag according to another embodiment of the present invention, FIG. 18 is a top view of the vent hole portion of the airbag, and FIG. FIG.

The airbag 70 is provided with a substantially semicircular vent hole 75. The airbag 70 has the same configuration as the above-described airbag, and has an opening 72 at a rear portion thereof for receiving gas from the inflator.
The airbag 70 is made of cloth and has an opening 7.
A plurality of bolt or rivet insertion holes 74 are provided in the second peripheral portion 73, and the airbag 70 can be connected to a container of the airbag device by the bolts or rivets.

The vent hole 75 is provided on the rear surface of the airbag 70. In a state before the airbag 70 is inflated (that is, a state in which the airbag 70 is folded and stored in the container) and in a state where the airbag internal pressure at the initial stage of the inflation is equal to or lower than a predetermined pressure, the vent hole 75 is Covered. The cover 76 is made of a cloth or resin sheet having a substantially similar shape to the vent hole 75 and having a surface area of a substantially semicircular shape overlapping the vent hole 75 larger than that of the vent hole.

The vent hole 75 has an arc-shaped portion 75a and a chord-shaped portion 75b. Also, the cover 76 is
a and a chordal portion 76b.

The cover 76 has an arcuate portion 76a and a chordal portion 76b on the surface thereof, each of which has an arcuate portion 7 of the vent hole 75.
5a and the chordal portion 75b are arranged along the inner surface of the airbag 70 so as to overlap with the peripheral edges of the airbag 70 and cover the vent hole 75.
The portion of the cover 5 which overlaps with the arc-shaped portion 75a is joined by means of a sewing thread 77, a bonding means such as adhesion or welding, and the chord-shaped portion 76b of the cover 76 is not joined to the chord-shaped portion 7 of the vent hole 75.
5b (hereinafter, a portion overlapping with the vent hole 75 of the cover 76 in a non-coupling manner may be referred to as a non-coupling portion).

Further, as shown in FIG.
Is provided with a notch-shaped concave portion 76c. When the cover 76 is arranged at a predetermined position, the recess 76 c extends from the edge of the chordal portion 76 b toward the inside of the opening of the vent hole 75, and
It is configured to form an opening that opens a part of the vent hole 75 together with the edge of the fifth chord-shaped portion 75b.
The opening formed by the concave portion 76c and the chord-shaped portion 75b forms a communicating portion 78 that communicates the inside and the outside of the airbag 70.

The cover 76 overlaps with the periphery of the vent hole 75 when the internal pressure of the airbag is lower than a predetermined pressure, and closes most of the vent hole 75. When the internal pressure of the airbag becomes higher than the predetermined pressure, the gas pressing force is applied. As a result, the non-joined portion protrudes outside the vent hole 75. Here, “most” means about 80 to 99.8% of the opening area of the vent hole 75.

When the vent hole 75 is formed in the airbag 70, the chordal portion 75b of the vent hole 75 is formed so as to extend along the weave of the cloth material of the airbag 70, thereby inflating the airbag. Due to the tension at the time, the vent hole 75 is greatly deformed,
Is formed, it is possible to prevent the strength of the airbag 70 from being significantly reduced.

The cover 76 may be made of the same material as the airbag 70 or may be different. However, when the cover 76 is deformed by a gas pressure higher than a predetermined pressure,
The cover 76 has relatively high elasticity with respect to the periphery of the vent hole of the airbag 70 so that the non-joined portion of the cover 76 protrudes outside the vent hole 75 smoothly. For example, when the cover 76 is made of the same cloth material as the airbag 70 in this embodiment, the weave of the cloth material of the cover 76 is inclined with respect to the extending direction of the chordal portion 76b of the cover 76. The cover 76 is configured to extend and contract relatively easily in the extending direction of the chord-shaped portion 76b and in a direction orthogonal to the extending direction. The angle at which the weave of the cloth material of the cover 76 obliquely extends with respect to the extending direction of the chord-shaped portion 76b is preferably about 30 ° to 60 °.

The airbag 70 has a peripheral portion 73 connected to a container by bolts or the like. The airbag 70 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection operation, the airbag 70 starts to inflate, the lid is opened, and the airbag 70 is deployed in the vehicle interior.

The airbag 70 is firstly blown by gas from an inflator introduced into the inside through the opening 72.
It is developed into the shape shown in FIG.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts to operate, the airbag 70 is folded, and the cloth materials constituting the airbag 70 are brought into close contact with each other. ing. At this time,
The inside and the outside of the airbag 70 are communicated with each other by a communication portion 78, and the outside air is introduced from the communication portion 78 with the inflation of the airbag 70, whereby the closely adhered cloth materials are separated from each other. The airbag 70 is easily inflated.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, most of the vent hole 75 is
The airbag 70 is inflated rapidly because a large amount of gas generated from the inflator does not flow out of the vent hole 75. When the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, the cover 76 is deformed by the pressing force of the gas, and the non-joined portion of the cover 76 is pushed out of the vent hole 75. As a result, the opening amount of the vent hole 75 increases, and excess gas inside the airbag flows out. Thereby, when an occupant enters the airbag 70, the airbag 70
Excess gas inside flows out through the vent hole 75 and the shock applied to the occupant is absorbed.

FIG. 20 is an exploded perspective view of a vent hole portion of an airbag according to another embodiment of the present invention, FIG. 21 is a top view of the vent hole portion of the airbag, and FIG.
The figure is a perspective view from the rear when the airbag is deployed.

The airbag 80 is provided with a circular vent hole 85. The airbag 80 has a configuration similar to that of the above-described airbag, and has an opening 82 at a rear portion thereof for receiving gas from the inflator. The airbag 80 is made of cloth and has an opening 82.
A plurality of bolts or rivets insertion holes 84 are provided in the peripheral portion 83 of the airbag 80, and the airbag 80 can be connected to the container of the airbag device by these bolts or rivets.

The vent hole 85 is provided on the rear surface of the airbag 80. In a state before the airbag 80 is inflated (that is, a state in which the airbag 80 is folded and stored in the container) and a state where the airbag internal pressure at the initial stage of the inflation is equal to or lower than a predetermined pressure, the vent hole 85 is made of cloth or resin. It is covered by a substantially semicircular cover 86 composed of a sheet or the like.

As shown in FIG. 21, the cover 86 has an arc portion 86a and a chord portion 86b.

The cover 86 is arranged along the inner surface of the airbag 80 such that the arc-shaped portion 86a overlaps the periphery of the vent hole 85 and the chord-shaped portion 86b extends across the vent hole 85. At this time, the cover 86 closes a large part of the vent hole 85 and opens a part of the vent hole 85 by an opening portion surrounded by the periphery of the vent hole 85 and the chordal portion 86b. .
An opening formed by the peripheral portion of the vent hole 85 and the chord-shaped portion 86b is a communication portion 88 that communicates the inside and outside of the airbag 80. Arc-shaped part 86 of cover 86
The overlapped portion between a and the vent hole 85
And bonding means such as bonding and welding.

The cover 86 closes most of the vent hole 85 when the internal pressure of the airbag is lower than a predetermined pressure,
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the airbag expands due to the pressing force of the gas and protrudes outside the vent hole 85 to increase the opening amount of the vent hole 85 as shown in FIG. Here, “most” refers to 80 to 9 of the opening area of the vent hole 85.
It means about 9.8%.

The cover 86 may be made of the same material as that of the airbag 80 or may be different. However, the cover 86 is extended by a gas pressure higher than a predetermined pressure and is surely out of the vent hole 85. In order to protrude, the cover 86 has relatively high elasticity with respect to the periphery of the vent hole of the airbag 80. For example, when the cover 86 is made of the same cloth material as the airbag 80 in this embodiment, the weave of the cloth material of the cover 86 is inclined with respect to the extending direction of the chordal portion 86b of the cover 86. The cover 86 is configured to extend and contract relatively easily in the extending direction of the chordal portion 86b and in a direction perpendicular to the extending direction. The angle at which the weave of the cloth material of the cover 86 is oblique to the extending direction of the chord-shaped portion 86b is 30.
The angle is preferably about 60 to 60 °.

The airbag 80 has a peripheral portion 83 connected to a container by bolts or the like. Then, the airbag 80 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection operation, the airbag 80 starts to inflate, the lid is opened, and the airbag 80 is deployed in the vehicle compartment.

The airbag 80 is opened by the gas from the inflator introduced into the interior through the opening 82.
It is developed into the shape shown in FIG.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts to operate, the airbag 80 is folded, and the cloth materials constituting the airbag 80 are brought into close contact with each other. ing. At this time,
The inside and the outside of the airbag 80 are communicated with each other by a communication portion 88, and the outside air is introduced from the communication portion 88 with the inflation of the airbag 80, whereby the closely adhered cloth materials are separated from each other. The airbag 80 starts deploying quickly.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, the vent hole 85 is mostly covered with the cover 86.
The gas generated from the inflator does not flow out from the vent hole 85 in a large amount, so that the airbag 80 is rapidly inflated. Then, when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 86 is extended by the pressing force of the gas and pushed out of the vent hole 85. As a result, the vent hole 85
The opening amount of the airbag increases, and the gas inside the airbag flows out. Thereby, when the occupant enters the airbag 80, the gas in the airbag 80 flows out through the vent hole 85 to the outside, and the impact applied to the occupant is absorbed.

FIG. 23 (a) is a top view of a vent hole portion of an airbag according to still another embodiment, and FIG. 23 (b) is a sectional view taken along the line BB of FIG. 23 (a). , Second
FIG. 4 is a perspective view of a vent hole portion when the airbag is deployed.

As shown in FIG. 23 (a), the airbag 90 is provided with a circular vent hole 91. Although not shown, the airbag 90 has the same configuration as the above-described airbag, and has an opening for receiving gas from the inflator at a rear portion thereof. The airbag 90 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening. The bolts or rivets allow the airbag 90 to be inserted into a container of the airbag device. It is possible to connect.

The vent hole 91 is provided on the rear surface of the airbag 90. A state before the airbag 90 is inflated (that is, a state where the airbag 90 is folded and stored in a container).
When the internal pressure of the airbag is equal to or lower than a predetermined pressure at the initial stage of inflation, the vent hole 91 is covered with a cover 92 made of a cloth or a resin sheet.

As shown in FIG. 23 (a), the cover 92
Is a substantially circular part 9 having a larger diameter than the vent hole 91.
2a and a projecting portion 92b projecting from a part of the edge of the circular portion 92a. The cover 92 is disposed along the inner surface of the airbag 90 such that the peripheral edge of the circular portion 92a substantially concentrically overlaps the peripheral edge of the vent hole 91. Then, the cover 92 thus arranged
An annular holding member 95 having an inner diameter smaller than the diameter of the circular portion 92a and an outer diameter larger than the diameter of the circular portion 92a is provided at a peripheral portion of the airbag 90 facing inward. ,
It substantially concentrically overlaps with the circular portion 92a and the vent hole 91.

In the vicinity of the center of the circular portion 92a of the cover 92, a part of the vent hole 91 is opened, and the airbag 90 is opened.
Is provided with a small hole-shaped communicating portion 93 that communicates the inside and outside. In addition, a slit 94 cut from the edge of the circular portion 92a and opposite to the overhang portion 92b with the communicating portion 93 interposed therebetween and communicating with the communicating portion 93 is formed.
Is provided. As a result, the vent hole 91
The cover 92 is partially open and largely closed.

The cover 92 is attached to the airbag 9 at the overhanging portion 92b by a joining means such as sewing thread 97 or bonding or welding.
0 is connected to the periphery of the vent hole 91. In addition, the holding member 95 is fixed to the circular portion 9 of the cover 92 together with the overhang portion 92b by a sewing thread 97 or a joining means such as adhesion or welding.
The airbag 90 is connected to the periphery of the vent hole 91 of the airbag 90 so as to surround the outer periphery of 2a. The circular portion 92a of the cover 92 is not connected to the airbag 90 and the holding member 95. This circular portion 92a is
Is held between the peripheral edge of the vent hole 91 and the peripheral edge on the inner peripheral side of the holding member 95, and is held so as not to come out illegally.

When the internal pressure of the airbag is equal to or lower than a predetermined pressure, the circular portion 92a of the cover 92 is held by the peripheral portion of the vent hole 91 of the airbag 90 and the holding member 95, thereby closing most of the vent hole 91. When the internal pressure of the bag becomes equal to or higher than a predetermined pressure, the circular portion 92 is deformed into a tongue shape by the pressing force of the gas, comes out of the space between the airbag 90 and the holding member 95, and protrudes outside the vent hole 91. . The "most" here
Means 80 to 99.8% of the opening area of the vent hole 91
Refers to the degree.

Note that the cover 92 may be made of the same material as the airbag 90, or may be different.

The airbag 90 has a peripheral portion connected to a container by bolts or the like. And this airbag 90
Is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. In the event of an automobile collision or the like, the inflator performs a gas ejection operation, the airbag 90 starts to inflate, the lid opens, and the airbag 90 deploys in the vehicle interior.

The airbag 90 is developed into a shape similar to that of the above-described embodiment by gas from an inflator introduced into the inside through an opening at the rear.

Although not shown, in the initial stage of the inflation of the airbag immediately after the inflator starts to operate, the airbag 90 is folded and the airbag 90 is folded.
Are in close contact with each other. At this time, the inside and the outside of the airbag 90 are communicated with each other by the communication portion 93, and the outside air is introduced from the communication portion 93 as the airbag 90 inflates, so that the closely adhered cloth materials are formed. Is easily separated, and the airbag 90
Begins to deploy quickly.

Thereafter, when the internal pressure of the airbag is lower than the predetermined pressure, the circular portion 92a of the cover 92 is
And the holding member 95 holds the vent hole 91 so as not to come out of the vent hole 91.
1 is largely closed by a cover 92,
Since a large amount of gas generated from the inflator does not flow out of the vent hole 91, the airbag 90 expands rapidly. When the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, the circular portion 92a of the cover 92 is deformed by the pressing force of the gas and comes out of the space between the airbag 90 and the holding member 95. Extruded toward the outside. As a result, the opening amount of the vent hole 91 increases, and excess gas inside the airbag flows out. Thus, when an occupant enters the airbag 90, excess gas in the airbag 90 flows out through the vent hole 91 to the outside, so that the impact applied to the occupant is absorbed. Become.

FIG. 25 (a) is a top view of a vent hole portion of an airbag according to still another embodiment, and FIG. 25 (b) is a sectional view taken along the line BB of FIG. 25 (a). , Second
FIG. 6 is a perspective view of a vent hole portion when the airbag is deployed.

As shown in FIG. 25A, the airbag 100 is provided with a circular vent hole 101. Although not shown, the airbag 100 has the same configuration as the above-described airbag, and has an opening for receiving gas from the inflator at a rear portion thereof. The airbag 100 is made of cloth,
A plurality of bolt or rivet insertion holes are provided in the periphery of the opening, and the airbag 100 can be connected to a container of the airbag device by these bolts or rivets.

The vent hole 101 is provided on the rear surface of the airbag 100. In a state before the airbag 100 is inflated (that is, a state in which the airbag 100 is folded and stored in a container) and in a state where the internal pressure of the airbag at the initial stage of the inflation is equal to or lower than a predetermined pressure, the vent hole 100 is made of cloth or resin. It is covered by covers 102 and 103 composed of sheets and the like.

As shown in FIG. 25 (a), the cover 10
The cover 102 has an arc-shaped portion 102a and a chordal portion 102b, and the cover 103 has an arc-shaped portion 103a and a chordal portion 103b. The chord-shaped portion 102b of the cover 102 is provided with a notch-shaped concave portion 102c from an edge near the center.

The airbag 100 and the cover 103 are arranged such that the arc portions 102a and 103a overlap the peripheral portion of the vent hole 101 and the chord portions 102b and 103b overlap with each other.
Are arranged along the inner surface of the. At this time, the chordal portion 102
b and the chordal portion 103b are overlapped so that the edge of the chordal portion 103b does not completely cover the recess 102c of the cover 102, and the edges of the recess 102c and the chordal portion 103b form an opening. It is arranged to be. The opening serves as a communication portion 105 that opens a part of the vent hole 101 and communicates inside and outside of the airbag 100. As a result, the vent hole 101 is
The cover 103 is partially open and most of the cover is closed. The overlapping portion between the arc-shaped portion 102a of the cover 102 and the arc-shaped portion 103a of the cover 103 and the vent hole 101 is formed with a sewing thread 104, an adhesive,
They are joined by joining means such as welding.

Both the cover 102 and the cover 103
When the internal pressure of the airbag is equal to or lower than the predetermined pressure, part of the vent hole 101 is opened and the main part is closed as described above, and when the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, the vent hole 101 is expanded by the pressing force of the gas. As shown in FIG.
To increase the opening amount. Here, “most” means about 80 to 99.8% of the opening area of the vent hole 101.

The covers 102 and 103 may be made of the same material as that of the airbag 100 or may be different from each other. In order to protrude outside of 101, covers 102 and 103
The elasticity of the airbag 100 is relatively high with respect to the periphery of the vent hole. For example, in this embodiment, the cover 1 is made of the same cloth material as the airbag 100.
02, 103, the covers 102, 10
3 is configured such that the weave of the cloth material is oblique to the extending direction of the chordal portions 102b and 103b, and the covers 102 and 103 are chordal portions 102b and 103, respectively.
It is configured to relatively easily expand and contract in the extending direction of b and the direction perpendicular to the extending direction. Covers 102, 10
The angle at which the weave of the cloth material 3 obliquely crosses the extending direction of the chordal portions 102b and 103b is preferably about 30 ° to 60 °.

In the airbag 100, the peripheral edge of the opening at the rear is connected to the container by bolts or the like. The airbag 100 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection operation, the airbag 100 starts to inflate, the lid is opened, and the airbag is deployed in the vehicle compartment.

The airbag 100 is developed into a shape similar to that of the airbag of the above-described embodiment by gas from an inflator introduced through a rear opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts operating, the airbag 100 is folded,
00 are in close contact with each other.
At this time, the inside and the outside of the airbag 100 are communicated by the communication portion 105, and the outside air is introduced from the communication portion 105 along with the inflation of the airbag 100, so that the closely adhered cloth materials are Are easily separated from each other, and the airbag 100 starts deploying quickly.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, the vent hole 101 is mostly covered with the cover 1.
The airbag 100 is inflated rapidly because the gas generated from the inflator does not flow out from the vent hole 101 in a large amount.
Then, when the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, the cover 102 and the cover 103 are extended by the pressing force of the gas and pushed out of the vent hole 100. As a result, the opening amount of the vent hole 101 increases, and the gas inside the airbag flows out. This allows
When the occupant enters the airbag 100, the gas in the airbag 100 flows out through the vent hole 101, and the impact applied to the occupant is absorbed.

In this embodiment, the covers 102 and 103 are connected to the vent holes 10 of the airbag 100.
When the airbag 100 is joined to the peripheral portion of the airbag 100, a reinforcing cloth 106 having an opening 106a having substantially the same diameter as the vent hole 101 is arranged between the airbag 100 and the covers 102 and 103. The outer peripheral portion of the vent hole 101 is prevented from being damaged when the airbag 100 is inflated and the vent hole 101 is opened when the air bag 100 is inflated and when the vent hole 101 is opened. However, the configuration, arrangement, coupling method, and the like of the reinforcing cloth 106 are not limited thereto.

FIG. 27 (a) is a top view of a vent hole portion of an airbag according to still another embodiment, and FIG. 27 (b) is a sectional view taken along the line BB of FIG. 27 (a). , Second
FIG. 7 (c) is an explanatory view showing an aspect of a vent hole portion when the airbag is inflated in a cross section taken along line BB of FIG. 27 (a), and FIG. 28 is a vent hole portion when the airbag is inflated. It is a perspective view of.

As shown in FIG. 27 (a), a substantially rectangular vent hole 111 is provided in the airbag 110. Although not shown, the airbag 110
Has a configuration similar to that of the above-described airbag, and has an opening for receiving gas from the inflator at a rear portion thereof. The airbag 110 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening. The bolts or rivets allow the airbag 110 to be mounted on a container of the airbag device. It is possible to connect.

The vent hole 111 is provided on the rear surface of the airbag 110. In a state before the airbag 110 is inflated (that is, a state where the airbag 110 is folded and stored in the container) and in a state where the internal pressure of the airbag in the initial stage of the inflation is equal to or lower than a predetermined pressure, the vent hole 111 is made of cloth or resin. It is covered with an elongated strip-shaped cover 112 composed of a sheet or the like.

A vent hole 11 formed in a substantially rectangular shape
1 is a pair of a long side portion 111a and a short side portion 111, respectively.
b. Cover 112 formed in an elongated strip shape
Has a long side portion 112a. The width W of the cover 112 is shorter than the long side 111a of the vent hole 111 by a predetermined length.

In the cover 112, the extending direction of the long side portion 112a is orthogonal to the extending direction of the long side portion 111a of the vent hole 111, and the long side portion 112a and the vent hole 11
The airbag 110 is disposed along the inner surface of the airbag 110 so as to cross the vent hole 111 at a predetermined interval from the short side portion 111b.

At this time, the cover 112 is
1 is closed, but an opening that partially opens the vent hole 111 is formed by the edge of the short side 111b side of the vent hole 111 and the edge of the long side 112a of the cover 112. You. This opening is the airbag 1
A communication portion 114 communicates between the inside and the outside of the device 10. As a result, the vent hole 111 is partially opened by the cover 112 and largely closed.

The cover 112 is joined to the periphery of the vent hole 111 by means of a sewing thread 113 or a joining means such as adhesion or welding.

An opening 115a having substantially the same shape as the vent hole 111 is provided between the vent hole 111 and the cover 112. The opening 115a is connected to the periphery of the vent hole 111 to reinforce the periphery of the vent hole 111. A reinforcing cloth 115 is provided. The reinforcing cloth 115 may be made of a cloth or the like made of the same material as the airbag, or may be made of a different material. The reinforcing cloth 115 is joined together with the cover 112 at the periphery of the vent hole 111 by a joining means such as a sewing thread 113 or an adhesive or welding.

The cover 112 opens and partially closes the vent hole 111 when the internal pressure of the airbag is lower than a predetermined pressure as described above, and pushes the gas when the internal pressure of the airbag becomes higher than the predetermined pressure. It is extended by the pressure, protrudes outside the vent hole 111 as shown in FIG. 28, and increases the opening amount of the vent hole 111. Here, “most” means about 80 to 99.8% of the opening area of the vent hole 111.

Note that the airbag 110 is provided with the vent hole 1.
In forming the airbag 11, the long side portion 111a and the short side portion 111b of the vent hole 111 are formed so as to extend along the weave of the cloth material of the airbag 110. Vent hole 11
It is possible to prevent the strength of the airbag 110 from being significantly reduced due to the large deformation of the airbag 1 or the formation of the vent hole 111.

The cover 112 may be made of the same material as that of the airbag 110 or may be different from the airbag 110. In order to protrude, the cover 112 has relatively high elasticity with respect to the periphery of the vent hole of the airbag 110. For example, in this embodiment, the airbag 1
When the cover 112 is made of the same cloth material as that of the cover 10, the weave of the cloth material of the cover 112 is configured to be oblique to the extending direction of the long side portion 112 a, and the cover 112 is made long. It is configured to relatively easily expand and contract in the extending direction of the side portion 112a and in a direction orthogonal to the extending direction. The angle at which the weave of the cloth material of the cover 112 obliquely extends with respect to the extending direction of the long side portion 112a is preferably about 30 ° to 60 °.

In the airbag 110, the peripheral edge of the opening at the rear is connected to the container by bolts or the like. The airbag 110 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection operation, the airbag 110 starts to inflate, the lid is opened, and the airbag is deployed in the vehicle compartment.

The airbag 110 is developed into a shape similar to that of the airbag of the above-described embodiment by gas from an inflator introduced into the airbag 110 through a rear opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts operating, the airbag 110 is folded,
The cloth materials constituting 10 are in close contact with each other.
At this time, the inside and the outside of the airbag 110 are communicated with each other by the communication portion 114, and the outside air is introduced from the communication portion 114 along with the inflation of the airbag 110, so that the closely adhered cloth materials are separated from each other. Are easily separated from each other, and the airbag 110 starts deploying quickly.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, most of the vent hole 111 is
The airbag 110 is inflated rapidly because a large amount of gas generated from the inflator does not flow out from the vent hole 111 because the airbag 110 is closed by the airbag 12. And
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 112 extends due to the pressing force of the gas, and
It is pushed out to the outside of 10. As a result, the opening amount of the vent hole 111 increases, and the gas inside the airbag flows out. Thereby, when the occupant enters the airbag 110, the gas in the airbag 110 flows out through the vent hole 111 to the outside, and the impact applied to the occupant is absorbed.

In this embodiment, when the cover 112 is connected to the peripheral portion of the vent hole 111 of the airbag 110, the cover 112 is substantially the same as the vent hole 111 between the airbag 110 and the cover 112. Shaped opening 115a
A reinforcing cloth 115 having a sewing thread 1 is provided on the periphery of the vent hole 111 of the airbag 110 together with the cover 112.
13 to prevent the peripheral edge of the vent hole 111 from being damaged when the airbag 110 is inflated and when the vent hole 111 is opened. The arrangement and coupling method are not limited to these.

FIG. 29 (a) is a top view of a vent hole portion of an airbag according to still another embodiment, and FIG. 29 (b) is a sectional view taken along the line BB of FIG. 29 (a). , Second
FIG. 9 (c) is an explanatory view showing an aspect of a vent hole portion at the time of inflation of the airbag in a cross section along the line BB of FIG. 29 (a), and FIG. It is a perspective view of.

As shown in FIG. 29A, the airbag 120 is provided with a slit-shaped vent hole 121 having a predetermined opening width. Although not shown, the airbag 120 has the same configuration as the above-described airbag, and has an opening for receiving gas from the inflator at a rear portion thereof. In addition, this airbag 12
Numeral 0 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening so that the airbag 120 can be connected to a container of the airbag device by the bolts or rivets. I have.

The vent hole 121 is provided on the rear surface of the airbag 120. In a state before the airbag 120 is inflated (that is, a state where the airbag 120 is folded and stored in the container) and a state where the airbag internal pressure at the initial stage of the inflation is equal to or lower than a predetermined pressure, the vent hole 121 is made of cloth or resin. A substantially rectangular or band-shaped cover 12 made of a sheet or the like
2 is covered. The opening width of the vent hole 121 is larger than the opening diameter of the communication portion 124 described later.

[0147] The cover 122 covers the vent hole 121 along the inner surface of the airbag 120. Cover 112
A small hole-shaped communicating portion 114 is provided in the vicinity of the center. The cover 122 extends so that the pair of opposed edges are substantially parallel to the extending direction of the slit-shaped vent hole 121, and the communication portion 114 is
It is arranged so as to be exposed from.

The communication part 124 is provided with the vent hole 121.
Are opened to communicate the inside and outside of the airbag 120. As a result, the vent hole 121 is partially opened by the cover 122 and largely closed. The cover 122 is the vent hole 12
At the peripheral edge of the first part, the parts are joined by a joining means such as a sewing thread 123 and adhesion or welding.

An opening 125a having substantially the same shape as the vent hole 121 is provided between the vent hole 120 and the cover 122. The opening 125a is connected to the peripheral edge of the vent hole 121 to reinforce the peripheral edge of the vent hole 121. A reinforcing cloth 125 is provided. The reinforcing cloth 125 may be made of a cloth or the like made of the same material as the airbag, or may be made of a different material. The reinforcing cloth 125 is joined together with the cover 122 at the periphery of the vent hole 121 by a joining means such as a sewing thread 123 or adhesion or welding.

The cover 122 opens and partially closes the vent hole 121 when the internal pressure of the airbag is lower than a predetermined pressure as described above, and pushes the gas when the internal pressure of the airbag becomes higher than the predetermined pressure. It is extended by the pressure, protrudes outside the vent hole 121 as shown in FIG. 30, and increases the opening amount of the vent hole 121. Here, “most” means about 80 to 99.8% of the opening area of the vent hole 121.

The cover 122 may be made of the same material as that of the airbag 120 or may be different. However, the cover 122 is extended by a gas pressure higher than a predetermined pressure, so that the cover 122 extends outside the vent hole 121 without fail. In order to protrude, the cover 122 has relatively high elasticity with respect to the periphery of the vent hole of the airbag 120. For example, in this embodiment, the airbag 1
When fabricating the cover 122 with the same cloth material as that of the cover 20, the weave of the cloth material of the cover 122 is configured to be oblique to the extending direction of the edge, and the cover 122 is It is configured to relatively easily expand and contract in the extending direction of the peripheral portion and in the direction orthogonal to the extending direction. The angle at which the texture of the cloth material of the cover 122 obliquely intersects with the extending direction of the peripheral portion is preferably about 30 ° to 60 °.

In the airbag 120, the peripheral edge of the rear opening is connected to the container by bolts or the like. Then, the airbag 120 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection operation, the airbag 120 starts to inflate, the lid is opened, and the airbag is deployed in the vehicle compartment.

The airbag 120 is developed into a shape similar to that of the airbag of the above-described embodiment by gas from an inflator introduced into the airbag 120 through a rear opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts to operate, the airbag 120 is folded and the airbag 1 is inflated.
20 are in close contact with each other.
At this time, the inside and the outside of the airbag 120 are communicated with each other by the communication portion 124, and the outside air is introduced from the communication portion 124 along with the inflation of the airbag 120, so that the closely adhered cloth materials are Are easily separated from each other, and the airbag 120 starts to deploy quickly.

Thereafter, when the internal pressure of the airbag is lower than the predetermined pressure, most of the vent holes 121 are
The airbag 120 is inflated rapidly because a large amount of gas generated from the inflator does not flow out from the vent hole 121 because the airbag 120 is closed by the airbag 22. And
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 122 expands due to the pressing force of the gas and the vent hole 1
20 is pushed out. As a result, the opening amount of the vent hole 121 increases, and the gas inside the airbag flows out. Thereby, when the occupant enters the airbag 120, the gas in the airbag 120 flows out through the vent hole 121 to the outside, and the impact applied to the occupant is absorbed.

In this embodiment, when the cover 122 is connected to the periphery of the vent hole 121 of the airbag 120, the cover 122 is substantially the same as the vent hole 121 between the airbag 120 and the cover 122. Shaped opening 125a
A reinforcing cloth 125 having a sewing thread 1 is provided on the periphery of the vent hole 121 of the airbag 120 together with the cover 122.
23 to prevent the periphery of the vent hole 121 from being damaged when the airbag 120 is inflated and when the vent hole 121 is opened. The arrangement and coupling method are not limited to these.

FIG. 31 is an exploded perspective view showing the structure of an airbag according to still another embodiment, FIG. 32 (a) is a top view of a vent hole portion of the airbag, and FIG. 32 (b) is FIG. 32A is a sectional view taken along the line BB of FIG.
FIG. 3 is a perspective view of a vent hole portion when the airbag is inflated.

The airbag 130 has a substantially semicircular vent hole 131. Although not shown, the airbag 130 has the same configuration as that of the above-described airbag, and has an opening at its rear portion for receiving gas from the inflator. In addition, this airbag 13
Numeral 0 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening, so that the airbag 130 can be connected to a container of the airbag device by these bolts or rivets. I have.

The vent hole 131 is provided on the rear surface of the airbag 130. In a state before the airbag 130 is inflated (that is, a state in which the airbag 130 is folded and housed in a container) and in a state where the internal pressure of the airbag at the initial stage of the inflation is equal to or lower than a predetermined pressure, the vent hole 131 is made of cloth or resin. It is covered by a cover 132 composed of a sheet or the like.

The cover 132 has a semicircular large-diameter portion 132a having an arc portion 132c and a chord portion 132d, and a small-diameter portion 132b extending from the chord portion 132b and having a smaller diameter than the large-diameter portion 132a. are doing. The diameter of the small diameter portion 132b is slightly larger than the diameter of the vent hole 131.

The cover 132 has an air bag such that the arc-shaped portion 132c of the large-diameter portion 132a overlaps the periphery of the arc-shaped portion 131a of the vent hole 131, and the small-diameter portion 132b overlaps the edge of the chord-shaped portion 131b of the vent hole 131. The chordal portion 132 of the large diameter portion 132a is disposed along the inner surface of the
d is substantially parallel to the chordal portion 131b of the vent hole 131,
And a chordal portion 132d and a small diameter portion 132b of the cover 132.
Is arranged so as to be slightly exposed from the vent hole 131 along the chordal portion 131b.

A part of the cover 132 is exposed from the vent hole 131, and a part of the vent hole 131 is opened.
Small hole communicating portion 13 that communicates inside and outside of airbag 130
5 are provided. Thereby, the vent hole 131
Is partially opened by a cover 132 and largely closed.

The large-diameter portion 132a of the cover 132 is joined to the periphery of the vent hole 131 by a sewing thread 134 or a joining means such as adhesion or welding.

The small-diameter portion 132b of the cover 132 is held by the holding member 133 on the inner surface side of the airbag 130 so as to overlap the edge of the vent hole 131 of the airbag 130 on the chordal portion 131b side. The holding member 133 is arranged along the inner surface of the airbag 130 so as to overlap the surface of the small-diameter portion 132b facing the inside of the airbag 130, and sandwiches the small-diameter portion 132b together with the airbag 130. The holding member 133 has an arc-shaped portion 133a and a chord-shaped portion 133b.
2b, the chordal portion 133b substantially coincides with or substantially parallel to the chordal portion 131b of the vent hole 131 and is slightly separated from the opening of the vent hole 131. It is arranged so that it may extend. The holding member 133 may be made of a cloth or the like made of the same material as the airbag, or may be made of a different material. This holding member 133 is
Along with 32, at the periphery of the vent hole 131, it is connected with a sewing thread 134, by bonding means such as adhesion or welding.

When the internal pressure of the airbag is equal to or lower than a predetermined pressure, the cover 132 is provided with the vent hole 131 as described above.
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the small-diameter portion 132b is deformed by the pressing force of the gas and the small-diameter portion 132b comes out of the space between the airbag 130 and the holding member 133. As shown in the figure, it protrudes outside the vent hole 131 to increase the opening amount of the vent hole 131. Here, “most” means that the opening area of the vent hole 131 is 8%.
It means about 0 to 99.8%.

It should be noted that the vent hole 1 is provided in the airbag 130.
In forming the airbag 31, the chordal portion 131 b of the venthole 131 is formed so as to extend along the weave of the cloth material of the airbag 130, so that the venthole 131 becomes large due to the tension at the time of inflation of the airbag. It is possible to prevent the strength of the airbag 130 from being significantly reduced due to the deformation or the formation of the vent hole 131.

The cover 132 may be made of the same material as that of the airbag 130 or may be different from the airbag 130. In order to protrude, the cover 132 has relatively high elasticity with respect to the periphery of the vent hole of the airbag 130. For example, in this embodiment, the airbag 1
When fabricating the cover 132 with the same cloth material as that of the cover 30, the weave of the cloth material of the cover 132 is changed to the chordal portion 132d.
The cover 13 is configured so as to be oblique to the extending direction of the cover 13.
2 are configured to relatively easily expand and contract in the extending direction of the chordal portion 132d and in a direction perpendicular to the extending direction. The angle at which the weave of the cloth material of the cover 132 obliquely intersects with the extending direction of the chordal portion 132d is preferably about 30 ° to 60 °.

In the airbag 130, the peripheral edge of the opening at the rear is connected to the container by bolts or the like. Then, the airbag 130 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection, the airbag 130 starts to inflate, the lid is opened, and the airbag 130 is deployed in the vehicle interior.

The airbag 130 is developed into the same shape as the airbag of the above-described embodiment by the gas from the inflator introduced into the inside through the rear opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the inflator starts operating, the airbag 130 is folded, and
The cloth materials constituting 30 are in close contact with each other.
At this time, the inside and the outside of the airbag 130 are communicated with each other by the communication portion 135, and the outside air is introduced from the communication portion 135 along with the inflation of the airbag 130, so that the closely adhered cloth materials are formed. Are easily separated from each other, and the airbag 130 starts to deploy quickly.

Thereafter, when the internal pressure of the airbag is equal to or lower than the predetermined pressure, most of the vent holes 131 cover the cover 1.
The airbag 130 is inflated rapidly because a large amount of gas generated from the inflator does not flow out of the vent hole 131 because the airbag 130 is closed by the airbag 32. And
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 132 is extended by the pressing force of the gas, and
31 is pushed out. As a result, the opening amount of the vent hole 131 increases, and the gas inside the airbag flows out. Accordingly, when the occupant enters the airbag 130, the gas in the airbag 130 flows out through the vent hole 131 to absorb the shock applied to the occupant.

FIG. 34 (a) is a top view of a vent hole portion of an airbag according to still another embodiment, and FIG. 34 (b) is a sectional view taken along line BB of FIG. 34 (a). , Third
FIG. 5 is a perspective view of a vent hole portion when the airbag is inflated.

As shown in FIG. 34 (a), the airbag 140 is provided with a substantially C-shaped annular slit 141. Although not shown, the airbag 140
Has a configuration similar to that of the above-described airbag, and has an opening for receiving gas from the inflator at a rear portion thereof. The airbag 140 is made of cloth, and a plurality of bolts or rivets are provided in the periphery of the opening. The bolts or rivets allow the airbag 140 to be attached to a container of the airbag device. It is possible to connect.

The slit 141 is provided on the rear surface of the airbag 140. The area surrounded by the slit 141 is a tongue-shaped cover 142. This slit 1
A circular vent hole 144 in the center overlapped with the outer peripheral portion of the airbag 140 so as to cover the slit 141 along the outer surface of the airbag 140.
An annular holding member 143 is provided. A vent hole 144 provided at the center of the holding member 143
Is smaller than the diameter of the substantially annular slit 141, and the outer peripheral diameter of the holding member 143 is larger than the slit 141. The cover 142 covers the vent hole 144 so as to overlap the periphery of the vent hole 144 from the back side of the holding member 143.

The air bag 140 of the slit 141
A holding member 145 having substantially the same shape as that of the holding member 143 is provided on the inward side of the peripheral portion so as to cover the slit 141 along the inner surface of the airbag 140. An opening 145 a having substantially the same diameter as the vent hole 144 is provided at the center of the holding member 145.
4 are arranged concentrically. Holding member 1
The periphery of the opening 145a of the airbag 140 overlaps the periphery of the cover 142 from the inner surface side of the airbag 140, and together with the periphery of the vent hole 144 of the holding member 144, the cover 1
42 are sandwiched. Thereby, the cover 14
2 is held by the holding member 143 and the holding member 145 to prevent unauthorized removal.

Near the center of the cover 142, the holding member 1
A small-hole-shaped communicating portion 147 is provided at a position not covered by the holding member 43 and the holding member 145. This communication part 147
Opens a part of the vent hole 144 and the airbag 1
It communicates between the inside and outside of 40. This allows
Part of the vent hole 144 is opened by the cover 142, and most of the vent hole 144 is closed.

The holding member 143 and the holding member 145 both have a sewing thread 146 at the outer peripheral portion of the slit 141.
The airbag 140 is connected to the airbag 140 by connecting means such as bonding or welding. These holding members 143 and 145 are
The airbag 140 may be made of a cloth or the like made of the same material, or may be made of a different material.

The cover 142 opens part of the vent hole 144 and closes most of the vent hole 144 as described above when the internal pressure of the airbag is lower than a predetermined pressure, and pushes the gas when the internal pressure of the airbag becomes higher than the predetermined pressure. As a result of the deformation caused by the pressure, the peripheral portion of the vent hole 14 comes out of the space between the holding member 143 and the holding member 145, and as shown in FIG.
4 protrudes outside to increase the opening amount of the vent hole 144. Here, “most” refers to 80 to 9 of the opening area of the vent hole 144.
It means about 9.8%.

In the airbag 140, the peripheral edge of the rear opening is connected to the container by bolts or the like. The airbag 140 is folded and accommodated in a container, and a lid is attached to the container. The container is provided with an inflator. At the time of collision of a car or the like, the inflator performs gas ejection operation, the airbag 140 starts to inflate, the lid is opened, and the airbag deploys in the vehicle compartment.

The airbag 140 is developed into a shape similar to that of the airbag of the above-described embodiment by gas from an inflator introduced into the inside through a rear opening.

Although not shown, in the initial stage of inflation of the airbag immediately after the start of operation of the inflator, the airbag 140 is folded, and the airbag 140 is folded.
The cloth materials constituting 40 are in close contact with each other.
At this time, the inside and the outside of the airbag 140 are communicated with each other by the communication portion 147, and the outside air is introduced from the communication portion 147 with the inflation of the airbag 140, so that the closely adhered cloth materials are formed. Are easily separated from each other, and the airbag 140 starts deploying quickly.

Thereafter, when the internal pressure of the airbag is lower than the predetermined pressure, most of the vent holes 144
The airbag 140 is inflated rapidly because the gas generated from the inflator does not flow out from the vent hole 144 in a large amount because the airbag 140 is closed by the airbag 44. And
When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the cover 142 is deformed by the pressing force of the gas, and its peripheral portion is pulled out from between the holding member 143 and the holding member 145 and is pushed out of the vent hole 144. As a result, the opening amount of the vent hole 144 increases, and the gas inside the airbag flows out. Thereby, the airbag 1
When an occupant enters the airbag 44, the airbag 140
The gas inside flows out to the outside through the vent hole 144, and the impact applied to the occupant is absorbed.

The above embodiments can be applied to various airbags such as an airbag for a passenger seat, an airbag for a rear seat, and an airbag for a side, in addition to an airbag for a driver's seat. 34th
38 to 39 show the airbags 380 and 390 for the passenger seat, and FIG. 40 shows the airbag 400 for the side. 38
1, 391 denotes a gas inlet, 382, 392, 402 denotes a vent hole, and 383, 393, 403 denotes a cover (opened state) of the vent hole. Reference numeral 404 denotes an automobile seat.

[0184]

As described above, in the airbag of the present invention,
When the internal pressure of the airbag is less than the predetermined pressure, the cover opens part of the vent hole and closes most of it,
Even when the airbag is folded at the start of the inflation of the airbag and the panels constituting the airbag are in close contact with each other, the outside air is introduced from a part of the vent hole, so that the airbag can be quickly moved. The airbag is rapidly deployed because the gas does not flow out from the vent hole in large quantities. Therefore, according to the present invention, even if the capacity of the airbag is increased or the output of the inflator is reduced, the airbag can be deployed sufficiently quickly. Of course, in the airbag of the present invention, the cover increases the opening amount of the vent hole when the internal pressure of the airbag becomes equal to or higher than the predetermined pressure, so that the shock when the occupant enters the airbag is sufficiently absorbed. Further, it is also possible to configure so that the airbag internal pressure is maintained at an appropriate pressure.

According to the present invention, the switching between closing and opening of the vent hole by the cover is extremely reliable, the manufacture of the airbag is easy, and the degree of freedom in selecting the material of the cover and the like is large.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an airbag according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing an attached state of a cover of the airbag of FIG.

FIG. 3 is a plan view of a vent hole portion of the airbag of FIG.

FIG. 4 is an explanatory view showing an aspect of a cover during an inflation process of the airbag of FIG. 1;

FIG. 5 is a perspective view of the airbag of FIG. 1 in an open state of a vent hole portion.

FIG. 6 is an explanatory diagram showing an open state of a vent hole portion of an airbag according to a second embodiment of the present invention.

FIG. 7 is an explanatory diagram showing an open state of a vent hole portion of an airbag according to a third embodiment of the present invention.

FIG. 8 is a perspective view showing an airbag according to a fourth embodiment of the present invention.

FIG. 9 is an exploded perspective view showing an attached state of a cover of the airbag of FIG.

10 is an explanatory diagram showing a slit portion when the airbag internal pressure of the airbag in FIG. 8 is equal to or lower than a predetermined pressure.

FIG. 11 is an explanatory view showing a slit portion when the airbag internal pressure of the airbag in FIG. 8 becomes equal to or higher than a predetermined pressure.

FIG. 12 is a perspective view of a slit portion in a state where an exhaust port of the airbag of FIG. 8 is exposed.

13 is a plan view of a slit portion of the airbag of FIG. 8 including a cover having an elongated hole-shaped exhaust port.

FIG. 14 with a cover having a porous exhaust port
It is a top view of the slit part of the airbag of FIG.

15 is a plan view of a slit portion of the airbag of FIG. 8 including a cover having a substantially triangular exhaust port.

FIG. 16 is a plan view showing an open state of a slit portion of the airbag of FIG.

FIG. 17 is an exploded perspective view showing a configuration of a vent hole portion of an airbag according to another embodiment of the present invention.

18 is a top view of a vent hole portion of the airbag in FIG.

19 is a perspective view from the rear when the airbag of FIG. 17 is deployed.

FIG. 20 is an exploded perspective view showing a configuration of a vent hole portion of an airbag according to another embodiment of the present invention.

FIG. 21 is a top view of a vent hole portion of the airbag in FIG.

FIG. 22 is a perspective view from the rear when the airbag of FIG. 21 is deployed.

23A is a top view of a vent hole portion of an airbag according to another embodiment of the present invention, and FIG. 23B is a cross-sectional view taken along line BB of FIG.

FIG. 24 is a perspective view of a vent hole portion when the airbag of FIG. 23 is deployed.

FIG. 25A is a top view of a vent hole portion of an airbag according to another embodiment of the present invention, and FIG. 25B is a cross-sectional view taken along line BB of FIG.

FIG. 26 is a perspective view of a vent hole portion when the airbag of FIG. 25 is deployed.

27A is a top view of a vent hole portion of an airbag according to another embodiment of the present invention, FIG. 27B is a cross-sectional view taken along line BB of FIG. FIG. 7A is an explanatory view showing a mode of a vent hole portion when the airbag is inflated in a cross section taken along line BB of FIG.

FIG. 28 is a perspective view of a vent hole portion when the airbag of FIG. 27 is deployed.

FIG. 29A is a top view of a vent hole portion of an airbag according to another embodiment of the present invention, FIG. 29B is a cross-sectional view taken along line BB of FIG. FIG. 7A is an explanatory view showing a mode of a vent hole portion when the airbag is inflated in a cross section taken along line BB of FIG.

FIG. 30 is a perspective view of a vent hole portion when the airbag of FIG. 29 is deployed.

FIG. 31 is an exploded perspective view showing a configuration of an airbag according to another embodiment of the present invention.

32 (a) is a top view of a vent hole portion of the airbag of FIG. 31, and FIG. 32 (b) is a cross-sectional view taken along line BB of FIG.

FIG. 33 is a perspective view of a vent hole portion when the airbag of FIG. 31 is inflated.

34A is a top view of a vent hole portion of an airbag according to another embodiment of the present invention, and FIG. 34B is a cross-sectional view taken along line BB of FIG.

FIG. 35 is a perspective view of a vent hole portion when the airbag in FIG. 34 is inflated.

FIG. 36 is a top view showing a modification of the slit of the airbag of FIG. 8;

FIG. 37 is a top view showing a modification of the slit of the airbag of FIG. 8;

FIG. 38 is a perspective view of a passenger airbag according to the embodiment.

FIG. 39 is a perspective view of a passenger airbag according to the embodiment.

FIG. 40 is a perspective view of the side airbag according to the embodiment.

[Explanation of symbols]

1,10,20,50,70,80,90 Airbags 5,15,25,26,75,85,91 Vent holes 6,16,27,56,76,86,92 Covers 6c, 16a, 27a, 27b, 56a, 78, 88,
93 communication part 7, 17, 28, 57, 77, 87, 97 sewing thread 55 slit 58, 60, 62, 64 exhaust port 100, 110, 120, 130, 140 airbag 101, 111, 121, 131, 144 vent hole 102, 103, 112, 132, 142 Cover 105, 114, 124, 135, 147 Communication part 104, 113, 123, 134, 146 Sewing thread 380, 390 Passenger airbag 400 Side airbag

Continuation of the front page (72) Inventor Atsushi Uchiyama 1-4-30 Roppongi, Minato-ku, Tokyo Inside Takata Corporation (72) Inventor Advisor Ulshin 1-4-30 Roppongi, Minato-ku, Tokyo Takata Corporation F term (reference) 3D054 AA01 AA06 CC13 CC14 CC15 CC16 FF03 FF10 FF16

Claims (6)

[Claims] 1. An airbag having a vent hole for allowing gas inside the airbag to flow out, comprising a cover that opens a part of the vent hole and closes a large part of the vent hole. When the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, part of the airbag protrudes outside the vent hole due to gas pressure,
Thus, the airbag is characterized in that the opening amount of the vent hole is increased. 2. The airbag according to claim 1, wherein the cover is provided with a communication portion that constantly communicates inside and outside of the airbag, and a part of a vent hole is opened by the communication portion. . 3. The structure according to claim 1, wherein a part of the edge of the cover is separated from the edge of the vent hole toward the inside of the vent hole, so that the vent hole is partially open. An airbag characterized by the following. 4. The airbag according to claim 1, wherein a part of a periphery of the vent hole of the airbag is coupled to the cover, and another part of the periphery of the vent hole is not coupled to the cover. An airbag characterized in that at least the non-joined portion protrudes outside the airbag to increase the opening amount of the vent hole. 5. An airbag having a vent hole for letting out gas inside the airbag, a cover for covering the vent hole is provided, and the cover is provided with an exhaust port and a small hole. The hole is always in communication with the inside and outside of the airbag, and the exhaust port is covered by the periphery of the vent hole of the airbag until the internal pressure of the airbag becomes a predetermined pressure or more. An airbag characterized by being exposed when it comes. 6. The vent hole according to claim 5, wherein the vent hole has a slit shape having a predetermined opening width, and when the internal pressure of the airbag exceeds a predetermined internal pressure, the slit is pushed open to expose the exhaust port. Airbags.