JP2001354094A - Air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag capable of absorbing the kinetic energy of an occupant quickly and sufficiently right after the inflation of the air bag followed by the reception of the occupant. SOLUTION: The air bag 1 comprises a pair of side panels 2, 2 and a front panel 3 sewed together, with an opposite-to-occupant face 4 at the end. Each side panel 2 has a vent hole 6. These side panels 2, 2 are tied together with an internal panel 7 arranged to be almost parallel to the opposite-to-occupant face 4 during the inflation of the air bag and the air bag 1 is prevented from expanding almost parallel to the opposite-to-occupant face 4. Accordingly, if the air bag 1 has an insufficient inner pressure during the inflation, a gas in the air bag is compressed quickly and sufficiently right after the occupant is forced into the air bag 1, to produce an increase in air-bag inner pressure and permit the reception of the occupant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag which inflates in an emergency to protect a human body, and more particularly to an airbag whose shape when inflated is restricted.

[0002]

2. Description of the Related Art As is well known, an airbag is applied to, for example, an occupant protection device of an automobile. Generally, such an airbag is formed in a bag shape from a cloth material or the like, and is configured to be able to flexibly change its shape.
The occupant protection device provided with such an airbag has an inflator for generating gas for inflating the airbag, and in an emergency such as a vehicle collision, the inflator is operated to eject gas to release air. Gas is supplied to the bag, the airbag is inflated, and the airbag is deployed in the vehicle interior to protect the occupant.

[0003] Such an airbag usually has an occupant-facing surface that faces an occupant's chest or the like in an inflated state (hereinafter, a side of such an airbag on which the occupant-facing surface is disposed). Is called "front end" or "front",
The side facing the occupant-facing surface may be referred to as “rear end side” or “rearward”. ).

At the time of a vehicle collision, the occupant rushes into the occupant-facing surface with a large kinetic energy due to the impact of the collision. At this time, the airbag receives a passenger by generating a reaction force due to the internal pressure of the gas filled therein. Usually, such an airbag is provided with a vent hole for letting out the gas inside, and after the occupant rushes into the airbag, the gas inside the airbag is made to flow out from this vent hole. In addition, it is possible to prevent the internal pressure of the airbag from excessively rising, and the occupant-facing surface gently retreats by the pressing force from the occupant while giving an appropriate reaction force to the occupant, thereby smoothly absorbing the kinetic energy of the occupant. become able to.

[0005] Fig. 15 is an explanatory view schematically showing a change in the mode when the inflated airbag absorbs the kinetic energy of the occupant. In FIG. 15, (a) is a diagram showing the state of the airbag immediately after the occupant has plunged into the inflated airbag, and (b) is a diagram showing the state of the airbag in the process of absorbing the kinetic energy of the occupant. FIG.

[0006] When the inflator starts gas injection in an emergency such as a vehicle collision, the airbag is first inflated to a substantially fully opened shape shown by a two-dot chain line in FIG. Becomes Immediately after the occupant has plunged into the inflated airbag, the occupant-facing surface of the airbag is flexibly deformed in accordance with each part of the occupant, generates a reaction force due to its internal pressure, and receives the occupant. . Then, the airbag absorbs the kinetic energy of the occupant by causing the gas inside the airbag to flow out from the vent hole, thereby gently retreating the occupant-facing surface without giving an excessive reaction force to the occupant, Protect crew.

[0007]

However, in such an airbag, after the inflator operates to blow out the gas and inflates the airbag, the occupant enters the airbag with high kinetic energy. In some cases, the airbag internal pressure may be slightly lower.

In such a case, the occupant may squeeze the airbag without obtaining a sufficient reaction force from the airbag until the occupant is inserted into the airbag and is received by the airbag. It is necessary to move and increase the internal pressure of the airbag by itself, which delays the start of absorption of the kinetic energy of the occupant by the airbag.

One of the methods for solving such a problem is to increase the output of an inflator which is a source of the gas. However, a high-output inflator is expensive, and an airbag or a fitting is required. Therefore, it is necessary to design these other parts with high strength, which is not preferable in terms of cost, weight, and the like.

The inventors of the present invention have found that when the airbag internal pressure has not reached a sufficient value at the time when the occupant plunges into the airbag, the start of absorption of the occupant's kinetic energy by the airbag is greatly delayed, In addition, the airbag is so flat that the distance between the occupant-facing surface and the rear end of the airbag is significantly reduced. It is possible to deform so that it expands in a substantially parallel direction, and the gas inside the airbag easily flows to the side of the airbag, so the gas compression effect due to the receding surface facing the occupant is small. Was found to be a factor.

According to the present invention, the expansion of the airbag in a direction substantially parallel to the occupant-facing surface is restrained to reduce the amount of lateral deformation of the airbag, and the internal pressure of the airbag becomes insufficient when the occupant enters. Even if it is enough, immediately after the occupant rushes, the gas inside the airbag is quickly and sufficiently compressed, the internal pressure of the airbag is increased to absorb the kinetic energy of the occupant, and the occupant facing surface is sufficiently sufficient. It is an object of the present invention to provide an airbag that is secured in size and that can firmly support an occupant that has rushed into the occupant facing surface.

[0012]

An airbag according to the present invention comprises:
An airbag having an occupant-facing surface facing an occupant's chest is provided with an internal panel connecting left and right or upper and lower sides of the inflated airbag to prevent expansion of the airbag in a direction substantially parallel to the occupant-facing surface. It is characterized by being carried out. It is preferable that the inner panel is disposed so as to be substantially parallel to the occupant-facing surface when the airbag is inflated.

According to the airbag of the present invention, the left and right or upper and lower opposing side surfaces are connected by an internal panel disposed substantially parallel to the occupant opposing surface. When the airbag inflates more than a predetermined amount due to the internal pressure of the airbag, or when the occupant plunges into the airbag and retreats the occupant-facing surface, the gas inside the airbag moves to the side to avoid the occupant-facing surface. Since the airbag does not expand in a direction substantially parallel to the occupant-facing surface, even if the airbag internal pressure is not sufficiently increased at the time when the occupant enters the airbag, the occupant may not face the occupant-facing surface. The gas inside the airbag is rapidly compressed and the airbag internal pressure rises before the airbag retreats substantially. And sufficiently to give rise to a reaction force receiving an occupant, it has become capable of absorbing the kinetic energy.

In the airbag of the present invention, the inner panel is partially folded and overlaps each other, and is connected by a connecting means. The connecting means applies a predetermined tension or more to the inner panel. Sometimes it is preferable to release the connection, in this case, even if a part of the inner panel is connected by a suture using a suture or the like that is torn when a predetermined or more tension is applied as the connecting means. Good.

With this configuration, when the airbag internal pressure is equal to or lower than the predetermined pressure when the airbag is inflated, a part of the internal panel is connected, and the side surfaces of the airbag facing each other are reduced in a state where the length is reduced. Can be connected. At this time, the interval between the opposing side surfaces connected by the internal panel of the airbag is smaller than the interval when the connected portions of the internal panel are connected in a non-coupled state, The expansion of the airbag is prevented, and the internal pressure of the airbag rapidly rises due to the gas ejection operation of the inflator. And
When an occupant thrusts into the airbag and the internal pressure of the airbag increases, both ends of the internal panel connecting the opposed sides of the airbag are pulled in directions opposite to each other with a tension of a predetermined value or more. For example, if the part of the inner panel is joined by a suture using a suture that breaks when a tension equal to or more than a predetermined value is applied, the suture is torn and the one part of the inner panel is broken. The inner panel is disengaged, and the side of the airbag connected by the inner panel is allowed to inflate in the direction of expansion of the airbag, and the internal pressure of the airbag excessively increases due to the increase in the volume of the airbag. Is prevented,
The airbag expands to the side of the occupant and sufficiently supports the occupant, and more stably receives the occupant near the center of the airbag.

The internal panel may be torn when a predetermined tension or more is applied.

In the airbag according to the present invention, the inner panel may be extended when a predetermined tension or more is applied instead of the above-described configuration, and the internal panel may be stretched when a predetermined tension or more is applied. It may be configured to be torn when it is taken.

With this configuration, the internal panel has the same effect as the above-described configuration. The inner panel shall be capable of being stretched or torn over a sufficient length so that the side surface of the airbag connected by the inner panel continues even after the airbag is allowed to expand in the airbag expansion direction. If the inner panel is stretched or torn, the tension (load) required for stretching or tearing of the inner panel turns into a resistance to bulging of the side portion of the airbag. Immediately after the inflation of the side is allowed, the airbag is prevented from suddenly expanding and its internal pressure is prevented from changing suddenly, and a part of the kinetic energy of the occupant who has plunged into the airbag is part of this internal panel. An airbag with an internal panel configured in this way can receive the occupant very smoothly and fully ride because it is spent as the load required for stretching or tearing. The ones that can absorb the kinetic energy. When the inner panel is configured to be extendable, it is preferable that the length of the inner panel be extended by 50 to 300% when the airbag is inflated to the maximum.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of an airbag for a passenger seat of an automobile as an airbag according to an embodiment of the present invention when inflation is completed, FIG. 2 is a partially sectional perspective view of the airbag,
FIG. 3 is a sectional view taken along the line III-III in FIG.

Airbag 1 for passenger seat shown in FIGS.
Has a substantially conical shape in which a pair of side panels 2 and a front panel 3 are stitched together, and a rear end portion thereof is tapered. A front end side of the airbag 1 is an occupant facing surface 4 for receiving an occupant when the airbag 1 is inflated in an emergency such as a vehicle collision, and has a rear end side. An opening 5 for introducing gas from an inflator (not shown) as a gas generation source for inflating the airbag 1 into the airbag 1 is provided. Further, the gas in the airbag flows out to each side panel 2 to prevent the internal pressure of the airbag from excessively increasing when an occupant enters the airbag 1 and to make the airbag 1 smooth. Is provided with a vent hole 6 for absorbing the kinetic energy of the occupant.

The left and right side panels 2 and 2 of the airbag 1 have predetermined opposing portions inside at an intermediate portion in the front-rear direction (the direction connecting the occupant facing surface 4 and the opening 5; the same applies hereinafter). They are connected to each other by a panel 7. The inner panel 7 is a planar member having a predetermined length and width. The inner panel 7 is disposed so as to be substantially parallel to the occupant facing surface 4 when the airbag 1 is inflated. Immediately after the occupant enters the airbag 1, the side panels 2, 2 are prevented from separating from each other by a predetermined distance or more. In the present embodiment, the inner panel 7 is made of a substantially rectangular cloth or a resin sheet or the like having a predetermined size, and is substantially parallel to the occupant facing surface 4 near the middle of the airbag 1 in the front-rear direction. It is located approximately at the center of the cross section.

The airbag 1 has an opening 5 at its rear end.
Is the opening of the airbag storage container (not shown)
Is connected to the periphery. An inflator is installed in this container (not shown), and gas generated from the inflator is introduced into the airbag 1 through these openings. This airbag 1 is folded and accommodated in a container. Then, a module cover (not shown) is attached so as to cover the opening of the container, and is installed on an instrument panel or the like (not shown) of an automobile.
In an emergency such as a vehicle collision, the airbag 1
Is inflated by the gas from the inflator that has been operated to eject gas, and is deployed in the vehicle interior.

At this time, the left and right side panels 2 and 2 of the airbag 1 are not separated from each other by a predetermined distance or more at an intermediate portion in the front-rear direction by an internal panel 7 arranged substantially parallel to the occupant facing surface 4. The middle portion of the airbag 1 is difficult to expand in a direction substantially parallel to the occupant facing surface 4 (in the present embodiment, as shown in FIG. The airbag 1 in the state where the airbag 1 is completed is rather configured such that the middle portion of the airbag 1 is narrowed toward the inside of the airbag along a cross section substantially parallel to the occupant facing surface 4, and the inner panel 7 Thus, the volume is smaller than when the side panels 2 and 2 are expanded without being connected to each other.)

As a result, the gas from the inflator is transferred to the occupant facing surface 4 of the airbag 1 during the inflation of the airbag.
The internal pressure of the airbag 1 is rapidly increased, and the airbag 1 is quickly squeezed into the occupant-facing surface 4 of the airbag 1 without being wasted. Even if the internal pressure is insufficient, the airbag 1 does not expand in a direction substantially parallel to the occupant facing surface 4, and the gas inside the airbag is rapidly increased before the occupant retreats the occupant facing surface 4 significantly. Is compressed, the internal pressure of the airbag rises, and the occupant can be received early.

Of course, after the airbag 1 has received the occupant, the gas inside the airbag flows out of the vent hole 6, and the occupant facing surface 4 slowly retreats while giving a sufficient reaction force to the occupant. Absorb the kinetic energy of the occupants.

Referring to FIG. 4, a conventional airbag constructed in the same manner as the airbag 1 except that the airbag 1 and an internal panel connecting the side panels on both sides are not provided. The effect of the airbag of the present invention will be described in comparison with a bag.

FIG. 4 (a) is a graph showing the change over time of the reaction force exerted on the occupant by the airbag when the occupant plunges into the airbag when the airbag is inflated. b) is a graph showing a change in the reaction force of the airbag with respect to the retreat amount of the occupant-facing surface. FIG. 4 (a),
In each figure of (b), a thick solid line indicates a change in the reaction force of the airbag 1 of the present invention, and a thin solid line indicates a change in the reaction force of the conventional airbag. In order to obtain these graphs, the airbag 1 of the present invention and the airbag of the conventional type are installed in airbag devices having the same configuration, and then inflated under the same conditions. The same occupant was pushed into each of the airbags, and the time-dependent change of the reaction force of each airbag toward the occupant and the amount of retreat of the occupant-facing surface were measured.

[0029] In the graph of 4 (a), the time t ₀ indicates the time at the moment that occupant hits the airbag, for each of the airbag 1 as well as conventional air bag of the present invention, the occupant together At the same time we are rushing. As is clear from this graph, the airbag 1 of the present invention exerts a reaction force on the occupant substantially immediately after the occupant has plunged into the airbag 1, and at the peak of the reaction force of the airbag 1 t _h is faster than the peak time t _j of the reaction force of a conventional air bag. From this, the airbag 1 of the present invention
It can be seen that the occupant receives the occupant earlier and sufficiently and absorbs its kinetic energy as compared with the conventional airbag.

From the graph of FIG. 4 (b), it can be seen that the airbag 1 of the present invention begins to exert a reaction force on the occupant when the amount of retreat of the occupant facing surface 4 is relatively small.
Then, the peak value G _h of the reaction force of the airbag 1 is about 15% lower than the peak value G _j of the reaction force of a conventional airbag low and the load of the air bag 1 has on the occupant is alleviated It became clear.

FIG. 13 is an explanatory view schematically showing a change in the mode when the airbag 1 of the present invention absorbs the kinetic energy of the occupant. In Figure 13, (a) the figure (corresponding to time t ₀ in the graph of FIG. 4 (a)) shows an embodiment of a moment when rammed into the airbag 1 the occupant is inflated, (b) drawing ( shows the embodiment of the air bag 1 immediately after the time point of a) diagram (also corresponding to the time t _h), shows the embodiment of the airbag 1 in the middle of the time to absorb figure occupant kinetic energy (c). Note that these (a) to (c)
In each figure of the drawings, a two-dot chain line indicates a mode of a conventional airbag corresponding to a time point in each figure.

After the inflator is actuated at the time of a vehicle collision or the like, the airbag 1 of the present invention and the conventional airbag are inflated into the shapes shown in FIG. 13A, respectively, and are ready to receive the occupant. At this time, if the internal pressure of the airbag is insufficient, as described above, each airbag cannot apply a sufficient reaction force to the occupant from the time when the occupant enters, and the occupant faces the occupant facing surface. Must be retracted to crush the airbag and compress the gas inside the airbag to further increase the internal pressure of the airbag.

In this regard, in the airbag 1 of the present invention, the gas inside the airbag is immediately compressed immediately after the occupant enters and the internal pressure increases, and a sufficient reaction force is applied to the occupant early. And the occupant is received (FIG. 13 (b)). On the other hand, in the conventional airbag, even if the airbag is crushed by the occupant, it is difficult for the airbag internal pressure to increase due to the expansion of the side portion, and the occupant retreats the occupant facing surface significantly with a large moving speed. Only after the airbag of the present invention can a sufficient reaction force be applied, so that the occupant can be received at a later point in time than the airbag of the present invention. The distance between the occupant-facing surface and the rear end of the airbag is reduced, and the kinetic energy absorption of the occupant is inferior to that of the airbag 1 of the present invention.

In the airbag 1 of the present invention, even if the internal pressure of the airbag is not sufficiently increased at the time when the occupant enters, the internal pressure of the airbag immediately increases immediately after the occupant enters, and the airbag 1 faces the occupant. Since the occupant is received before the surface retreats significantly, the distance between the occupant-facing surface and the rear end of the airbag is kept large to sufficiently absorb the kinetic energy of the occupant (FIG. 13 (c)). Will be able to

In this embodiment, the inner panel 7 connects the left and right side panels 2 and 2 of the airbag 1 and expands the airbag 1 in the right and left and lateral directions substantially parallel to the occupant facing surface 4. Although it is configured so as to prevent the airbag 1, the configuration of the inner panel 7 is not limited to this.
May be configured so as to connect intermediate portions arranged on the upper side and the lower side of the vehicle to prevent expansion in the vertical direction substantially parallel to the occupant facing surface 4.

In the above embodiment, the airbag 1 is configured as a passenger airbag for an automobile.
The airbag of the present invention can be applied as an airbag for protecting a human body in various other uses. For example, the airbag 10 shown in FIGS. 5 and 6 is an example of application to an airbag for a driver's seat of an automobile. FIG. 5 is a perspective view of the airbag 10, and FIG. FIG.

The airbag 10 for the driver's seat of this car is:
Front panel 11 and rear panel 12 each having a circular shape
The front panel 11 has an occupant facing surface 13 near the center of the front panel 11 facing the occupant's chest and the like, and the rear panel 12 has a center near the center. Is provided with an opening 14 for an inflator (not shown), and a vent hole 15 for letting out the gas inside the airbag.

In the airbag 10, a pair of opposing edges are connected by an internal panel 16 inside the airbag. The inner panel 16 has a configuration similar to that of the inner panel 7 of the airbag 1 described above, and is a planar member having a predetermined width and length.
Are arranged so as to be substantially parallel to the occupant facing surface 13 in an inflated state, and the edges of the airbag 10 connected by the inner panel 16 are spaced from each other by a predetermined distance in a direction substantially parallel to the occupant facing surface 13. The above does not separate. The inner panel 16 is joined at its opposite ends to a pair of ears 17 extending from opposing portions of the peripheral edge of the rear panel 12 by joining means such as stitching, bonding, welding, or the like. Are connected to each other.

In the airbag 10, the periphery of the opening 14 is connected to a retainer of an airbag device (not shown) by bolts or the like. The retainer is provided with an inflator. In connecting the airbag 10 to the retainer, the tip of the inflator is introduced into the airbag 10 through the opening 14. After the airbag 10 is folded and covered with a module cover (not shown), the airbag 10 is installed on a steering wheel (not shown) of an automobile. Then, in an emergency such as a vehicle collision, the airbag 10 is inflated by the gas from the inflator that has been operated to eject the gas, pushes the module cover open, and deploys in the vehicle compartment.

The airbag 10 thus configured is
Similar to the above-described airbag 1, when the airbag is inflated and when the occupant enters the airbag 10, the occupant does not expand in a direction substantially parallel to the occupant facing surface 13, and the occupant enters the airbag 10. Even if the internal pressure of the airbag is insufficient at the time of completion, the gas inside the airbag is quickly and sufficiently compressed to increase the internal pressure of the airbag immediately after the occupant enters the airbag 10, and the occupant is received. be able to.

Also in this airbag 10, the inner panel 16 may be connected to left and right lateral sides substantially parallel to the occupant-facing surface 13 and similarly to the occupant-facing surface 13.
The opposite sides in the vertical direction that are substantially parallel to each other may be connected.

In the above embodiment, the inner panel is disposed near the center of the cross section substantially parallel to the occupant-facing surface at an intermediate portion in the front-rear direction of the airbag, but the arrangement of the inner panel is not limited to this. Instead, it can be changed according to the use or use conditions of the airbag. For example, as in an airbag 1A shown in FIG. 7, the inner panel 7A may be arranged on the upper half side of a cross section substantially parallel to the occupant facing surface 4 at an intermediate portion in the front-rear direction of the airbag 1A. FIG. 7 shows an airbag 1 according to this embodiment.
It is a partial section perspective view of A.

The airbag 1A is substantially parallel to the occupant-facing surface 4 by an inner panel 4A arranged so that a middle portion of each of the side panels 2 and 2 in the front-rear direction is substantially parallel to the occupant-facing surface 4. Except for being connected to each other in the upper half of the cross section, it has the same configuration as the airbag 1 described above, and the same reference numerals indicate the same parts.

According to the airbag 1A thus configured, when the airbag 1A is inflated and an occupant enters, the lower half of the airbag 1A is greatly deformed as compared with the upper half. Therefore, the lower half of the airbag 1A can receive the occupant more flexibly.

In the airbag 1A, the inner panel is disposed on the upper half of the airbag, but may be disposed on the lower half of the airbag. Thereby, the occupant can be more flexibly received on the upper half side of the airbag.

The dimensions of the inner panel can also be appropriately set according to the use of the airbag, the conditions of use, and the like. For example, when the interval connecting the side panels is reduced, the internal pressure of the airbag can be sufficiently increased even by using a lower output inflator, and each side panel extends along the extending direction of the occupant facing surface. When the vertical width of the connecting portion with the airbag is increased, the airbag can more uniformly receive the occupant.

In the above embodiment, the internal panel may be provided integrally with each panel constituting the airbag, or may be provided as a separate component. For example,
In the above-described airbag 10, the inner panel 16 is formed as a substantially rectangular shape separate from the front panel 11 and the rear panel 12, and both ends of the inner panel 16 are formed on the peripheral edge of the rear panel 12 as shown in FIG. Are attached to the airbag 10 by being coupled to a pair of ears 17 extending from the opposite portion of the airbag. FIG. 17 is an exploded perspective view showing the configuration of the airbag 10. As shown in FIG.

When the airbag 10 is manufactured, first, the front panel 11 and the rear panel 12 are overlapped so that one surface of each panel located outside the airbag 10 faces each other, The peripheral edges are joined together by joining means such as stitching. Next, the inner panel 16 is overlapped along the other surface of the front panel 11, and each ear 17 of the rear panel 12 is wrapped around the other surface of the front panel 11 to be joined to both ends of the inner panel 16. Thereafter, the airbag 10 is obtained by inverting the front panel 11 and the rear panel 12 through the inflator opening 14.

The airbag 10A shown in FIG. 9 has a configuration in which the above-mentioned rear panel ears are omitted.
FIG. 9 is an exploded perspective view showing the configuration of the airbag 10A.

The airbag 10A has a front panel 11A and a rear panel 12 like the airbag 10 described above.
A, the inner panel 16A is overlapped, and both ends of the inner panel 16A are wrapped around the rear panel 12A, and the peripheral portions of the front panel 11A and the rear panel 12A and the curved portions 18 provided at both ends of the inner panel 16A are formed. This is obtained by connecting the front panel 11A and the rear panel 12A through the inflator opening 14A after joining along the periphery of the rear panel 12A.

The curved portions 18 provided at both ends of the inner panel 16A have a shape in which the end of the inner panel 16A is recessed toward the center of the inner panel along the periphery of the rear panel 12A. Has become.

An airbag 10B shown in FIG. 10 has a structure in which a rear panel 12B and an internal panel constituting the airbag 10B are integrally formed. FIG. 10 is an exploded perspective view showing the configuration of the airbag 10B.

In the airbag 10B, a front panel 11B and a rear panel 12B are overlapped and their peripheral edges are connected to each other as in the case of the airbags 10 and 10A. A pair of strip-shaped connecting pieces 19 having a predetermined width and length are both extended from opposing peripheral portions of the peripheral portion of the rear panel 12B.

In the airbag 10B, as described above, the front panel 11B and the rear panel 12B are overlapped and their peripheral edges are joined together, and each connecting piece 19 is connected to the side of the front panel 11B that overlaps the rear panel 12B. It is obtained by turning the front panel 11B and the rear panel 12B through the opening 14B for the inflator after connecting the tips of the connecting pieces 19 by drawing around to the opposite side.

After the front panel 11B and the rear panel 12B have been turned over in this manner, the first panel 11B and the rear panel 12B are connected to each other.
The pair of connecting pieces 19 are arranged substantially parallel to the occupant-facing surface inside the airbag, and function as an internal panel connecting left and right sides of the airbag 10B.

The above-described substantially circular airbags 10, 10A,
10B, the left and right sides of the airbag are connected by an inner panel, but the invention is not limited to this. For example, the sides in the vertical direction may be connected.

In the above embodiment, each airbag is configured so that expansion in the direction substantially parallel to the occupant-facing surface when inflated is restrained by the internal panel. Other parts of the airbag, for example, a restraining means such as a strap that connects the occupant-facing surface and the rear end of the airbag to each other to restrain the airbag from expanding in the front-rear direction may be combined.

Further, as in an airbag 1B shown in FIG. 11, a pleated portion 20 is formed on the inner panel 7B by folding and joining the middle part thereof, and both ends of the inner panel 7B are pulled with a predetermined tension. Thus, the connection may be released to increase the length of the inner panel 7B. In the airbag 1B configured as described above, when the occupant enters the airbag 1B and the internal pressure of the airbag excessively increases, the connection of the pleat portion 20 is released to reduce the length of the inner panel 7B. By increasing the distance between the left and right side panels 2, 2, the volume of the airbag 1 is increased and the internal pressure of the airbag can be reduced, and the airbag 1 </ b> B extends to the side of the occupant. Since the occupant is expanded to support the occupant, the occupant can be more stably received near the center of the airbag.

Although not shown, the inner panel is provided with a fragile portion formed of a perforated slit or the like instead of the pleated portion 20 so that the inner panel becomes fragile when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure. The airbag may be configured so as to break from the portion and expand the airbag to the side, thereby reducing the airbag internal pressure.

The airbag 1C shown in FIG. 12 has a band-shaped inner panel 7C which connects the left and right side panels 2 and 2 and has a sufficient length. The pleated part 20A is joined by the tear seam 21 which is torn by tension.
And its length is reduced. The pleated portion 20A pulls both ends in the longitudinal direction of the inner panel 7C with a tension of a predetermined value or more, whereby the tear seam 21 is torn over an appropriate area according to the tension, and the tear of the inner panel 7C is reduced by the area. The joined portions are released from each other and separated from each other to increase the length of the inner panel 7C. Of course, internal panel 7
When the tension pulling both ends of C is not more than a predetermined value, the tear seam 21 of the pleated portion 20A does not tear and the length of the inner panel 7 does not increase illegally.
C is configured to connect the left and right side panels 2 and 2 to prevent expansion of the airbag 1C in a direction substantially parallel to the occupant-facing surface 4. A region where the tear seam 21 can be broken and separated from each other when the inner panel 7C is pulled by a predetermined tension, that is, the pleated portion 20A is joined by the tear seam 21 as described above.
Has a sufficient size.

FIG. 14 shows such a pleated portion 20A.
It is explanatory drawing which shows typically the change of the mode at the time of absorbing the kinetic energy of an occupant about the airbag 1C which has the inner panel 7C in which it formed. In FIG.
FIG. 3A shows the state of the airbag 1C immediately after the occupant has plunged into the inflated airbag 1C, FIG. 3B shows the state of the airbag 1C on the way of absorbing the kinetic energy of the occupant, and FIG. Shows an aspect of the airbag 1C immediately before the absorption of the kinetic energy of the occupant is completed.

In the event of an emergency in the event of a vehicle collision, when the inflator performs a gas ejection operation, the airbag 1C is first developed into a shape shown by a two-dot chain line in FIG. 14 (a) to receive the occupant. Become.

Immediately after the occupant squeezes into the inflated airbag, the airbag 1C is rapidly prevented from being expanded in a direction substantially parallel to the occupant facing surface 4 by the inner panel 7C. The airbag internal pressure increases.

Thereafter, when the internal pressure of the airbag becomes equal to or higher than a predetermined pressure, the left and right sides of the airbag 1C connected by the internal panel 7C are separated from each other at both ends of the internal panel 7C by a tension higher than a predetermined value. To the pleats 2 as described above.
0 of the tear seam 21 in an appropriate area of the inner panel 7C which has been joined to each other at the pleated portion 20.
Are separated from each other, and the length of the inner panel 7C increases. Since the pleated portion 20 has a sufficient size, the tearing of the tear seam 21 and the accompanying increase in the length of the inner panel 7C may be caused by the occupant's airbag 1C.
The passenger facing surface 4 is retracted, and the airbag internal pressure can be continuously maintained as long as the internal pressure of the airbag rises above a predetermined pressure. Then, due to the increase in the length of the inner panel 7C, the airbag 1C greatly expands to the side of the occupant to prevent the airbag internal pressure from excessively increasing and to support the occupant sufficiently. The occupant can be reliably received near the center of the airbag to protect the occupant. Further, due to the continuation of tearing of the tear seam 21 by the airbag 1C accompanying the increase in the length of the inner panel 7C, the tear seam 21 is always maintained.
As a result, a part of the kinetic energy of the occupant is consumed as a load for tearing the occupant, and the airbag 1C can more smoothly absorb more kinetic energy.

Although not shown, in place of the pleated portion 20A joined by the tear seam 21, the length of the inner panel is increased when a predetermined tension or more is applied to the inner panel. A tearable portion having a sufficient length to be torn may be formed. In an airbag having an inner panel having such a tearable portion, an airbag 1C having an inner panel 20C whose middle part is joined by the tear seam 21 described above.
The same effect is obtained. Further, the inner panel itself may be configured to be stretched when both ends are pulled with a predetermined tension. In the airbag having the inner panel which can be stretched with the predetermined tension as described above, the above-described airbag is used. The same effect as that of the bag 1C can be obtained. In addition, it is preferable that when the airbag is inflated to the maximum from the state before the inflation of the airbag, the length of the inner panel is extended by about 50 to 300%.

[0066]

As described in detail above, according to the airbag of the present invention, the airbag is in a direction substantially parallel to the occupant-facing surface when the airbag is inflated or when the occupant enters the airbag due to the inner panel. For example, during the inflation of the airbag, the gas from the inflator for inflating the airbag is not wasted by the inflation of the side of the airbag. Even when the airbag internal pressure is insufficient when the occupant enters the airbag, the gas inside the airbag is quickly and sufficiently compressed immediately after the occupant enters the airbag. As a result, the internal pressure of the airbag rises, and the occupant can be reliably received and its kinetic energy can be absorbed.

Further, the length of the inner panel is configured to increase when a predetermined tension is applied, and the length of the inner panel is increased when the internal pressure of the airbag becomes equal to or higher than the predetermined pressure. By expanding the airbag, it is possible to more stably support the occupant who has entered the airbag and to more reliably protect the occupant.

[Brief description of the drawings]

FIG. 1 is a perspective view of an airbag 1 according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional perspective view of the airbag of FIG.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4A is a graph showing a change over time of an airbag reaction force, and FIG. 4B is a graph showing an airbag reaction force with respect to a retreat amount of an occupant facing surface.

FIG. 5 is an airbag 10 according to another embodiment of the present invention.
It is a perspective view of.

FIG. 6 is a partial sectional perspective view of the airbag of FIG. 5;

FIG. 7 is a partial cross-sectional perspective view of an airbag 1A according to the embodiment.

FIG. 8 is an exploded perspective view of the airbag 10 according to the embodiment.

FIG. 9 is an exploded perspective view of an airbag 10A according to the embodiment.

FIG. 10 is an exploded perspective view of an airbag 10B according to the embodiment.

FIG. 11 is a partial sectional perspective view of an airbag 1B according to the embodiment.

FIG. 12 is a partial sectional perspective view of an airbag 1C according to the embodiment.

FIG. 13 is an explanatory diagram schematically showing a change in a mode at the time of absorbing kinetic energy of the occupant of the airbag according to the first embodiment of the present invention.

FIG. 14 is an explanatory diagram schematically showing a change in a mode at the time of absorbing kinetic energy of an occupant of an airbag according to another embodiment of the present invention.

FIG. 15 is an explanatory diagram schematically showing a change in a mode at the time of absorbing kinetic energy of an occupant of an airbag according to a conventional example.

[Explanation of symbols]

1, 1A, 1B, 1C, 10, 10A, 10B Airbag 4, 13 Occupant facing surface 7, 7A, 7B, 7C, 16, 16A Internal panel 19 Connecting piece

Claims (8)

[Claims] 1. An airbag having an occupant-facing surface facing an occupant's chest, wherein the inside connects the left and right side surfaces of the inflated airbag to prevent expansion of the airbag in a direction substantially parallel to the occupant-facing surface. An airbag comprising a panel. 2. An airbag having an occupant-facing surface facing an occupant's chest, wherein an interior connecting upper and lower side surfaces of an inflated airbag for preventing expansion of the airbag in a direction substantially parallel to the occupant-facing surface. An airbag comprising a panel. 3. The airbag according to claim 1, wherein the inner panel is arranged to be substantially parallel to the occupant-facing surface when the airbag is inflated. 4. The internal panel according to claim 1, wherein a part of the inner panel is folded back, overlaps with each other, and is connected to the inner panel by a connecting means. An airbag, wherein the connection is released when tension is applied. 5. The airbag according to claim 4, wherein the connecting means is a suture. 6. The airbag according to claim 1, wherein the inner panel extends when a predetermined tension or more is applied. 7. The airbag according to claim 1, wherein the inner panel is torn when a predetermined tension or more is applied. 8. The airbag according to claim 1, wherein the inner panel is torn when a predetermined tension or more is applied.