JPH0585295A - Air bag - Google Patents

Abstract

PURPOSE:To provide an air bag which can protect occupants at out of position from an impact due to inflating force of the air bag and secure protective ability for the occupants at normal position. CONSTITUTION:An outlet hole 2b is formed at an air bag 2, and a strap 4 is wound around this outlet hole 2b. One end of this strap 4 is secured 2d around the outlet hole 2b, while the other end is secured at the position close to the inflating direction of the air bag 2 rather than the outlet hole 2b so that the outlet hole 2b is throttled by tension of the strap 4 when the air bag 2 is inflated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device for protecting an occupant in a vehicle collision.

[0002]

2. Description of the Related Art Conventionally, as such an airbag device, for example, an airbag device described in Japanese Utility Model Laid-Open No. 2-38360 is known. In this conventional airbag device, a slit is formed in the airbag substantially parallel to the direction of deployment.

Therefore, in this conventional airbag device,
After deploying with high pressure gas, the slit is opened due to the deformation of the airbag due to the contact with the occupant, and the high pressure gas inside leaks, which temporarily reduces the internal pressure of the airbag and reduces the pressing force against the occupant. The slits are closed to prevent leakage of high-pressure gas when the occupant is not in contact with the airbag, which prevents the inflation rate of the airbag from decreasing and further reduces Even after the operation, the internal pressure of the airbag can be kept at a predetermined value.

[0004]

By the way, generally, the time until the vehicle collides and the occupant collides with the instrument panel or the like is very short. Therefore, in the airbag device, the airbag is inflated in a short time. There is a need.
Furthermore, in order to obtain the desired protection performance of the airbag, the deployment time is set so that the occupant collides after the internal pressure of the airbag is sufficiently increased.

However, this deployment time is set on the condition that the occupant is in a predetermined posture such as a driving posture, and the occupant is in a position different from usual (hereinafter, this position is out of position). Seated in), the following problems arise. That is, when the occupant is seated in the out-of-position position closer to the instrument panel than the predetermined position, the occupant collides with the airbag earlier. However, at this time, since the internal pressure of the airbag is being increased and the airbag is rapidly deployed, the impact in the airbag deployment direction is applied to the occupant (2 in FIG. 4).
See the dotted line). By the way, such an out-of-position is likely to occur particularly in the front passenger seat whose posture is not regulated, but also in the driver's seat, for example, when the driver likes the posture in which the driver approaches the steering wheel.

Further, if the rise of the internal pressure is suppressed in consideration of such a problem, the pressure at the time of a collision of an occupant at a normal time becomes insufficient, and it is necessary to set so as to obtain a development satisfying both of them. Very difficult.

The present invention has been made by paying attention to the conventional problems as described above, and protects an occupant located out of position from an impact due to the deploying force of an airbag, and also protects an occupant in an ordinary position. It is an object of the present invention to provide an airbag device capable of ensuring passenger protection performance.

[0008]

In the present invention, the above-mentioned object is achieved by making the area of the exhaust hole provided in the air bag variable so as to be narrowed in accordance with the expansion degree of the air bag.

That is, the air bag device of the present invention is an air bag device in which a folded air bag accommodated in a front position of an occupant is expanded by high-pressure gas when a vehicle collides with the air bag. An exhaust hole having an area is formed, and the exhaust hole is provided with throttle means capable of narrowing the hole area. The throttle means is operated in a direction of narrowing the hole area in accordance with the expansion degree of the airbag. A means for providing interlocking means is provided.

[0010]

When the vehicle collides, high-pressure gas is supplied into the airbag, and the airbag folded up to that point is expanded by the high-pressure gas. At the initial stage of deployment, part of the high-pressure gas is discharged from the exhaust hole to the outside of the airbag, so the rate of increase in internal pressure is low.

Then, as the degree of deployment of the airbag advances,
The interlocking means causes the throttle means to throttle the exhaust hole according to the degree of expansion of the airbag. Therefore, the rate of increase in internal pressure increases in accordance with the degree of throttling, and reaches a predetermined internal pressure at the end of deployment.

Therefore, when the occupant is out of position and collides with the airbag at an early stage during the deployment of the airbag, the opening of the exhaust hole of the airbag is large at this time. Since the internal pressure is low and the deployment force of the airbag is small, the occupant can be protected from the impact of the deployment force of the airbag.

On the other hand, when the occupant is positioned at the predetermined position, the occupant collides with the airbag while the internal pressure of the airbag is sufficiently increased.
With the airbag, the occupant can be reliably received and the occupant can be protected from a collision with the instrument panel, etc., and the pressure in the airbag due to the occupant's collision allows the gas in the airbag to be appropriately released to the outside. The internal pressure of the airbag is reduced, and the impact exerted on the occupant by the reaction force of the airbag is reduced.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. In this embodiment, an airbag device for protecting the passenger on the passenger side will be described as an example.

First, the airbag device of the first embodiment will be described.

To explain the structure, FIG. 1 is a developed state view showing an airbag apparatus of the first embodiment, and in the figure, 1 indicates an airbag case. The airbag case 1 is provided in an instrument panel (not shown) in front of the passenger seat, and an airbag 2 is accommodated inside the instrument panel.

In a normal state, the airbag 2 is folded small as shown in FIG. 3, and the air supply port 2a on the base end side is connected to the inflator 3 provided in the front part of the airbag case 1. ing. When the vehicle collides, the high pressure gas from the inflator 3 is supplied to the air supply port 2a.
The air bag 2 is inflated, and the air bag 2 is thereby inflated. The rear surface of the airbag case 1 is closed by a lid 1a which is opened vertically and horizontally by the impact of the airbag 2 when it is deployed.

An exhaust hole 2b is formed in the airbag 2. The exhaust holes 2b are for the purpose of gradually releasing the gas in the airbag 2 to the outside in order to absorb the impact when the occupant collides with the airbag 2, and as described later, the internal pressure when the airbag 2 is deployed. It is provided for the purpose of controlling the rate of increase.

That is, the exhaust hole 2b is slightly opened at a position close to the air supply port 2a of the airbag 2, and as shown in detail in FIG. 2 which is an enlarged view of the portion A of FIG. A string insertion hole 2c is formed in an annular shape at the peripheral position of the exhaust hole 2b on the inner surface of the bag 2. The string insertion hole 2c can be formed by folding the material forming the airbag 2 around the periphery of the exhaust hole 2b, or can be formed by sewing a separate long bag-shaped material. it can.

The string insertion hole 2c has one end 2f.
Is opened toward the deployment direction of the airbag 2, and the drawstring 4 is inserted into the string insertion hole 2c from this one end 2f,
The end portion 2e of the throttle string 4 on the insertion side is fixed to the airbag 2 at the other end 2g of the cord insertion hole 2c, and the other end portion 2d of the throttle string 4 is in the deployment direction from the exhaust hole 2b of the airbag 2. It is fixed to the side position. Then, the drawstring 4 is tense with the airbag 2 deployed to the maximum,
This allows the throttle string 4 to be narrowed so that the diameter of the exhaust hole 2b is reduced.
Has been set. That is, in this throttle string 4, the portion wound around the exhaust hole 2b corresponds to the throttle means in the claims, and the portion wound from the portion wound around the exhaust hole 2b to the end portion. The part up to 2d corresponds to the interlocking device.

A guide member 5 for guiding the sliding of the drawstring 4 is fixed to the airbag 2 near the one end 2f of the string insertion hole 2c.

Next, the operation of the embodiment will be described step by step with reference to FIGS. FIG. 4 is a hole diameter characteristic and bag internal pressure characteristic diagram on the horizontal axis of time, where the solid line is the hole diameter curve, the one-dot chain line is the bag internal pressure curve, and the two-dot chain line is the conventional bag internal pressure curve. .

(B) Normal Time In a normal time when no collision occurs in the vehicle, as shown in FIG. 3, the airbag 2 is folded small in the airbag case 1 and the throttle cord 4 is It is in a slackened state, so that the exhaust hole 2b is maintained in a largely opened state. That is, as shown in FIG.
The diameter of the exhaust hole 2b is maximum and the internal pressure of the airbag 2 is zero.

(B) At the start of airbag deployment High-pressure gas is injected and supplied from the inflator 3 into the airbag 2 due to the collision of the vehicle, whereby the airbag 2 begins to deploy as shown in FIG. The state of the exhaust hole 2b and the state of the internal pressure of the airbag 2 at this time correspond to those of FIG. 4, and as shown in the figure, the squeezed cord 4 which has been loose until that time becomes tense as the airbag 2 is deployed. First, the exhaust hole 2b is slightly throttled, and the internal pressure is slightly increased.

Thereafter, as the airbag 2 is deployed, the tension of the throttle string 4 advances and the exhaust hole 2b is gradually narrowed, so that the internal pressure of the airbag 2 rises while the rate of increase of the internal pressure gradually increases.

The air bag 2 is further expanded and the exhaust hole 2
As b is squeezed, as shown in FIG.
When is completely deployed, the internal pressure becomes maximum as shown in FIG. In addition, the hole of the exhaust hole 2b is, as shown in FIG.
It is narrowed down to the maximum before the maximum deployment of the airbag 2.

By the way, the time when the collision performance is displayed after that in FIG. 4 is the time when the occupant collides with the airbag 2 in the normal posture, so that the occupant collides after the maximum deployment. The time required for maximum deployment is set.

When the occupant collides after the stage where the airbag 2 is completely deployed in this way, the airbag 2
Since the internal pressure of the vehicle is sufficiently increased, it is possible to reliably receive the occupant and protect the occupant from the collision with the instrument panel or the like. Further, when the pressing force due to the collision of the occupant acts on the airbag 2, the gas inside the airbag 2 is appropriately released to the outside from the exhaust hole 2b, so that the internal pressure of the airbag 2 gradually decreases, and as a result, The reaction force of the airbag 2 reduces the impact on the occupant.

(C) At the time of out-of-position When the occupant is not in a predetermined posture and is in the out-of-position, and the collision with the airbag 2 occurs early, that is, when the occupant is out of position in FIG. In the case of collision at the time indicated as “of position”, since the exhaust hole 2b is still being narrowed down at this time, the internal pressure of the airbag 2 is not yet sufficiently increased (sufficiently lower than the conventional one), Therefore, even if the occupant collides with the airbag 2 at this stage, the airbag 2 is not strongly impacted by the deploying force of the airbag 2.

As described above, in the airbag device of this embodiment, the occupant positioned at the predetermined predetermined position can be protected from the impact due to the collision of the vehicle, and the occupant can be protected from the impact. It has a feature that it is possible to protect an occupant from an impact caused by a rapid deployment force of the airbag 2 even when the airbag is located at the out position.

Next, the airbag device of the second embodiment of the present invention shown in FIG. 5 will be described. In describing the second embodiment, the same components as those in the first embodiment will be designated by the same reference numerals, and the description thereof will be omitted. Only the differences will be described.

In the second embodiment, the return preventing means 6 for restricting the sliding of the throttle string 4 in the direction in which the exhaust hole 2b expands is provided. That is, in this embodiment, the diaphragm string 4
In the portion wound around the exhaust hole 2b, protrusions 6b are formed at predetermined intervals, and the inner side of the guide member 5 allows passage of the throttle string 4 in the direction of narrowing the exhaust hole 2b, but in the opposite direction. Piece 6a that engages with the projection 6b and blocks passage to
Is provided.

Therefore, in the second embodiment, since the diameter of the exhaust hole 2b narrowed down by the expansion of the airbag 2 can be maintained in the narrowed state, the occupant after the airbag 2 is expanded is inflated by the occupant. When the vehicle collides with the vehicle 2, a sufficient damping force can be generated by the exhaust hole 2b that maintains the narrowing, so that the passenger protection performance can be more reliably maintained.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and even if there are design changes and the like within the scope not departing from the gist of the present invention. Included in the present invention. For example, in the embodiment, the throttle string is provided on the inner surface side of the airbag, but it may be provided on the outer surface side. Further, one end of the drawstring may be fixed to any position of the airbag as long as it is in a tension state when the airbag is deployed, or may be fixed to other than the airbag. Further, in the embodiment, the airbag device which protects the passenger on the passenger side is shown, but it can be applied to the driver side as well, and in this case, it is provided in the central portion of the steering wheel or the like.

Further, in the embodiment, the throttle cord wound around the exhaust hole is shown as the throttle means, but the point is that any means capable of narrowing the exhaust hole can be moved along the exhaust hole, for example. Other means such as a simple shutter or a small bag-like member that swells to narrow the exhaust hole may be used. When a shutter is used as the diaphragm means, the diaphragm string can be moved in the closing direction in conjunction with the deployment of the airbag, as in the embodiment.

Further, in the embodiment, the diaphragm string is used as the interlocking means, but various interlocking means can be applied depending on the diaphragm means. For example, when the diaphragm means is in the form of a shutter and is actuated by an actuator or the like, it may be control means for driving the actuator with a slight delay in the deployment operation of the airbag. Further, when the throttle means is in the form of a bag, it is possible to interlock by introducing high-pressure gas to be supplied to the airbag through the orifice. In this case, the orifice serves as the interlocking means.

[0037]

As described above, in the airbag apparatus of the present invention, the airbag is provided with the exhaust hole and the throttling means, and the interlocking means is used to throttle the exhaust hole in accordance with the expansion degree of the airbag. As a result, it is possible to protect the occupants who are in the predetermined positions from the impact of a vehicle collision, and of course, because the occupants are in the out-of-position, Even if the air bag comes into contact with the airbag at an early stage, sufficient exhaust from the exhaust hole can protect the occupant from the impact of the deployment force of the airbag.

[Brief description of drawings]

FIG. 1 is a sectional view of an airbag device of a first embodiment of the present invention in a developed state.

FIG. 2 is a detailed view showing an enlarged part A of FIG.

FIG. 3 is an operation explanatory view of the first embodiment device.

FIG. 4 is a characteristic diagram showing a hole diameter characteristic of an exhaust hole and an inner pressure characteristic of an airbag when the apparatus of the first embodiment is deployed.

FIG. 5 is an enlarged view showing a main part of the second embodiment of the present invention.

[Explanation of symbols]

 2 Airbag 2b Exhaust hole 2d End 2e End 4 Throttle string 6 Return prevention means

Claims (1)

[Claims] 1. An air bag device in which an air bag accommodated in a front position of an occupant in a folded state is inflated with high-pressure gas when a vehicle collides, wherein an exhaust hole having a predetermined area is formed in the air bag, The exhaust hole is provided with throttling means capable of throttling the hole area, and interlocking means for actuating the throttling means in the direction of throttling the hole area in accordance with the expansion degree of the airbag. An airbag device characterized in that