GB2267065A

GB2267065A - A side-impact airbag system

Info

Publication number: GB2267065A
Application number: GB9310153A
Authority: GB
Inventors: Wolfgang Henseler; Luigi Brambilla; Manfred Muller; Guido Wetzel
Original assignee: Daimler Benz AG; Mercedes Benz AG
Current assignee: Daimler Benz AG
Priority date: 1992-05-23
Filing date: 1993-05-17
Publication date: 1993-11-24
Anticipated expiration: 2013-05-17
Also published as: JPH0664492A; JP3012892B2; GB9310153D0; DE4217176C2; DE4217176A1; GB2267065B

Abstract

The airbag 4 is arranged in the already unfolded state and approximately in the desired set position for an accident, with the result that it exercises its protective action with particular rapidity when gas is introduced. <IMAGE>

Description

2 2 6 7,065 A side-impact airbag system The invention relates to a

side-impact airbag system for vehicles, having an airbag (gas cushion) which is arranged to the side of a vehicle seat on a side wall or door of the vehicle and is inflated automatically in a sideways collision of the vehicle in order to protect the person on the abovementioned vehicle seat.

The basic principles of airbag systems are known and they are already built into vehicles as standard fittings. In the case of these standard airbags, the systems concerned are frontal-impact systems, which are intended to protect the driver or passenger of a passenger vehicle or the like from striking the windscreen or the dashboard or the like. With airbags of this kind, a gas generator is combined with a folded gas cushion, generally arranged under a protective cover which is opened or blown open when the gas cushion is inflated and directs the unfolding gas cushion in a desired direction.

In connection with frontal-impact airbag systems for protecting the frontseat passenger, it is known from German Offenlegungsschrift 2,063,478 to incorporate the folded gas cushion into the padding of a front wall or a dashboard in such a way that the surfaces of these parts lie in a common plane. It is possible in this way to achieve an airbag which is especially large when inflated and, in an emergency, is capable of filling a large part of the space between the front-seat passenger and the front wall of the vehicle or dashboard.

In airbag systems which are intended to protect the driver in a frontal impact, a smaller size is generally sufficient because here the airbag unfolds between the steering wheel and the driver and hence in a relatively small free space.

It is, in principle, known from GB-A 22 20 620 to arrange airbag systems on vehicle side walls or doors as 2 well in order to improve protection for the vehicle occupants in a sideways collision of the vehicle. According to GB-A 22 20 620, the airbag has a relatively large volume after inflation and unfolding, extending over virtually the entire height of the side wall or door and also covering a window opening.

According to German Offenlegungsschrift. 4,119,788, which is not a prior publication but is based on an earlier application, an airbag which serves to provide protection in sideways collisions can be arranged in a lower area of a side wall or door behind a lining component which, when the air bag is inf lpted, is pushed in the direction of the vehicle interior, swivelling in the process, and exposes an upwardly oriented opening on the side wall or door, from which a normally folded part of the airbag can then emerge to form a cushion.

A similar arrangement is known from US Patent 4,966,388. Here too, the airbag is arranged under a lining component which is pushed out towards the interior of the vehicle by the airbag at the beginning of the process of inflation of the airbag. A previously folded part of the airbag is then inflated to form a cushion.

It is known from US Patent 3,791,667 to arrange a multiplicity of smaller airbags in the interior of the vehicle, including on the vehicle side walls or doors. Here, the airbags are formed by membranes capable of great expansion which normally form a smooth side wall of a hollow body to which air can be introduced.

From JP-A 2-249 740 it is known to arrange in vehicle side walls or doors an air tank which is compressed in a sideways collision of the vehicle, whereupon an airbag communicating with the air tank is inflated.

The previous designs of side-impact airbag systems still do not have a satisfactory effect. This is due above all to the fact that the period of time required to bring the airbag into a state in which it provides protection is very large in comparison with the available time. Allowance 3 must here be made f or the f act that vehicles have only minimal crumple zones in the sideways direction to mitigate the ef f ect of the collision on the occupants. The conditions which apply to side-impact airbag systems are fundamentally dif f erent from those which apply to frontal- impact airbag systems.

The arrangement of thick cushioning parts in the interior of the vehicle on the side walls or doors is known from GB-A 14 41 598. These cushioning parts are admittedly continuously effective. However, the protective effect is markedly less than that of airbag systems. Moreover, the continuously present cushioning parts restrict the free space in the interior of the vehicle to a marked extent.

The present invention seeks to make a considerable improvement to the effectiveness of side-impact airbag systems.

According to the present invention, in a side-impact airbag system of the type indicated at the outset by the fact that the airbag is arranged in a (very largely) unfolded state and (to a very large extent) in the desired set position for a sideways collision and hence comes into effect virtually without delay when gas is introduced.

Preferably, the airbag is arranged under a sheetlike side-wall or sidedoor lining which is connected releasably or via an expansion joint to the side wall or door. Alternatively, the airbag may be arranged under a sheet-like side-wall or side-door lining which is expandable or consists of expandable sheet material.

The general concept underlying the invention is to arrange an airbag in the set position, all that is necessary in the event of danger then being the filling of the airbag and this can take place at particularly high speed because the time required in previous airbag systems to unfold the airbag is already available for the generation of the desired internal pressure.

At the same time, use is made of the realisation that comparatively large cavities in which the unfolded 4 airbag can be accommodated to a very large extent in the set position are available in vehicle side walls or doors, so that all that is necessary in the event of danger is for the space occupied by the airbag to be enlarged by the inflation process in order to achieve the desired protective effect.

The invention also takes account of the realisation that the maximum volume of the airbag in the impact-inflated state is of less significance for a good protective effect of a side-impact airbag system than the rapidity with which the impact-inflated state is reached. Another reason why the rapidity is so great in the invention is that the envelope of the airbag is tautened almost immediately when gas is introduced and continues to be held taut as it is expanded, enlarging the airbag volume.

An advantageous embodiment of the invention will now be described by way of example with reference to the drawing.

The drawing shows in the single figure a vehicle side door with a sideimpact airbag system designed in accordance with the invention.

Arranged on the inner side (visible in the drawing) of a vehicle side door, in the cavity between the internal door lining 1 and the outside of the door, in the region of a vehicle seat (not shown) is a side-impact airbag system 2. This comprises a gas generator 3, which is aligned parallel to the bottom edge of the door, and an already unfolded gas cushion 4 arranged approximately in the set position which it is intended to adopt in the event of an accident involving a side impact. The gas cushion 4 is accordingly arranged virtually in the state ready for use; all that it requires is to be supplied with gas in order to stretch the cushion envelope taut and expand it with an accompanying enlargement of the volume of the gas cushion 4.

To ensure that the expansion of the gas cushion 4 cannot be hindered by the internal lining 1, the internal lining 1 can be connected releasably to structural parts of the door. It is possible, instead, to provide an expansion joint 5, allowing the internal lining 1 to be displaced comparatively easily towards the interior of the vehicle by the expanding gas cushion 4.

If required, the internal lining 1 can also consist of a sufficiently flexible material which can accompany the expansion movement of the gas cushion 4.

It is, in principle, also possible, moreover, within the invention to arrange or design the gas cushion 4 as part of the internal lining 1.

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Claims

1. A side-impact airbag system for vehicles with an airbag which is arranged to the side of a vehicle seat on a side wall or door of the vehicle and which is adapted to be inflated automatically in a sideways collision of the vehicle, wherein the airbag is arranged in the at least virtually completely unfolded state and substantially in the desired set position for effectiveness in a sideways collision so as to come into effect virtually without delay when gas is introduced into the airbag as a result of a sideways collision.

2. A system according to claim 1, wherein the airbag is arranged under a sheet-like side-wall or side-door lining which is connected releasably or via an expansion joint to the side wall or door.

3. A system according to Claim 1, wherein the airbag is arranged under a sheet-like sidewall or side-door lining which is expandable or consists of expandable sheet material.

4. A side-impact airbag system for vehicles, substantially as described herein with reference to and as illustrated in the accompanying drawing.