GB2511395A - Restraint system for a Vehicle - Google Patents

Abstract

A vehicle restraint system 10 comprises an airbag 12 with inflatable tethers 16, 18, 20. The inflatable tethers 16, 18, 20 are inflated by a multi-stage inflating device (26, fig 3) configured so the tethers are inflated in at least two consecutive stages. The tethers 16, 18, 20 may be hollow tubes and can be arranged either inside the airbag or outside the airbag 12. The tethers can have vents 28 internal to the main airbag 12. Where there are multiple tethers they can be inflated independently from each other and in consecutive stages. The tethers influence the shape of the airbag 12 and control of the timing of their inflation can be used to adjust the shape and position of the airbag 12 in dependency on the type of vehicle crash.

Description

Restraint System for a Vehicle The invention relates to a restraint system according to the preamble of patent claim 1 as well as a restraint system according to the preamble of patent claim 6.

Such a restraint system for a vehicle is known from US 5 372 381. The restraint system serves for restraining at least one passenger of the vehicle in the event of an accident.

The restraint system comprises at least one airbag movable from a stowage position into at least one restraint position. In the restraint position at least one gas storage chamber is bounded by the airbag. Moreover, the gas storage chamber is filled with a gas in the form of air in the restraint position so that a passenger can be cushioned by means of the airbag in the event of an accident.

The restraint system further comprises at least one inflatable volume element in the form of an inflatable rib. The restraint system in US 5 372 381 comprises a plurality of inflatable volume elements in the form of inflatable ribs. The respective volume element is movable from a stowage position into at least one use position in which a shape, in particular an external shape of the airbag is effected by means of the volume element in the restraint position of the airbag. In other words, the airbag is forced into a predeterminable shape in the restraint position by means of the inflatable ribs being in their use position.

Moreover, the restraint system comprises at least one inflating device in the form of a gas generator. The inflating device serves for inflating the inflatable ribs thereby moving the inflatable ribs from the stowage position into the use position.

It is an object of the present invention to further develop a restraint system of the previously mentioned kind in such a way that at least one passenger of a vehicle can be restrained particularly advantageously.

This object is solved by a restraint system having the features of patent claim 1 and a restraint system having the features of patent claim 6. Advantageous embodiments with expedient and non-trivial developments of the invention are indicated in the other patent claims.

A first aspect of the invention relates to a restraint system of the kind indicated in the preamble of patent claim 1. According to the present invention the inflating device is configured as a multi-stage inflating device capable of inflating the volume element in at least two consecutive stages. This means the volume element can be inflated by conveying a gas into the volume element by means of the inflating device during a first period of time in a first stage. Moreover, the volume element can be inflated by conveying a gas, particularly air, into the volume element by means of the inflating device during a second period of time in a second stage, the second period of time following the first period of time. For example, a third period of time can exist between the first period of time and the second period of time, wherein during the third period of time gas is not conveyed into the volume element by means of the inflating device. For example, during the first period of time (first stage) gas is conveyed into the volume element. During the consecutive third period of time the inflating device does not convey gas into the volume element. During the consecutive second period of time (second stage) gas is conveyed into the volume element by means of the inflating means again.

Thereby, the shape, in particular the external shape and, thus, the position of the airbag in the restraint position can be adjusted in a need-based manner and, for example, in dependency on at least one signal characterizing a crash of the vehicle. For example, the signal is provided by a crash sensor. Thus, the shape and the position of the airbag can be adjusted in dependency on the detected crash. Hence, the shape and the position of the airbag in relation to a passenger to be restrained by the airbag can be adjusted particularly advantageously so that the passenger can be cushioned and restrained by the airbag very effectively and efficiently. For example, the inflating device comprises at least two independent inflators. In other words, the inflating device can comprise multiple independent inflators by means of which the volume element can be inflated in the at least two consecutive stages.

In an advantageous embodiment of the invention the volume element is designed as a hollow tube.

In a further advantageous embodiment of the invention the volume element is arranged outside the airbag with respect to the restraint position of the airbag and the use position of the volume element.

In a further advantageous embodiment of the invention the restraint system comprises at least one further inflatable volume element movable from a stowage position into at least one use position in which the shape of the airbag is effected by means of the further volume element, the inflating device being configured to inflate the volume elements independently from each other and/or the further volume element in at least two consecutive stages. In this embodiment the restraint system is configured as a multiple chamber restraint system since a first chamber for storing gas is bounded by the first volume clement and a second chamber for storing gas is bounded by the second volume element. Thus, the position and the shape of the airbag can be adjusted in a need-based manner.

Preferably, the chambers can be filled with gas, in particular air, by means of the inflating device independently from each other so that the shape and the position of the airbag can be adapted to, for example, the type of the crash of the vehicle. In order to realize the multiple-stage inflation of the at least one volume element and/or the independent inflations of the volume elements, in a further advantageous embodiment of the invention the inflating device comprises at least two inflators capable of being activated independently from each other.

A second aspect of the invention relates to a restraint system of the kind indicated in the preamble of patent claim 6. According to the invention the inflating device is configured to inflate the volume elements independently from each other and/or in at least two consecutive stages respectively. Advantageous embodiments of the first aspect of the invention are to be regarded as advantageous embodiments of the second aspect of the invention and vice versa.

The restraint system according to the second aspect of the invention is configured as a multiple chamber restraint system since a first chamber for storing gas, in particular air, is bounded by a first one of the volume elements and a second chamber for storing gas, in particular air, is bounded by the second volume clement. Thereby, the position and the shape of the airbag can be adjusted in a need-based manner so that at least one passenger of the vehicle can be restrained particularly advantageously.

The restraint system according to the present invention can be used for, for example, the driver of the vehicle. For example, the restraint system can be arranged in a steering wheel, a roof, an instrument panel, a centre console, a door, or an A-pillar of the body of the vehicle. Moreover, the restraint system according to the present invention can be used for a front passenger. For example, the restraint system can be arranged in the roof, the instrument panel, the centre console! a door, or an A-pillar of the body. This means the restraint system 10 can be used as a driver airbag, as a passenger airbag and as a side airbag.

Moreover the restraint system according to the present invention can be used for second row seats or seats arranged thereafter. For example, the restraint system can be arranged in the roof, at the back of a front scat, at the floor, at a tunnel, on a B-pillar of the body, in a door, in a C-pillar or a D-pillar of the body.

Further advantages, features and details of the invention derive from the following description of a preferred embodiment as well as from the drawing. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respective indicated combination but also in any other combination or taken alone without leaving the scope of the invention.

The drawing shows in: Fig. 1 a schematic top view of a restraint system for a vehicle, the restraint system comprising an inflating device by means of which at least one volume element can be inflated in at least two consecutive stages and/or at least two volume elements of the restraint system can be inflated independently from each other; Fig. 2 a schematic sectional view of the restraint system; Fig. 3 part of a schematic sectional view of the restraint system; Fig. 4 a schematic front view of the restraint system; and Fig. 5 a schematic side view of the restraint system.

Figs. 1 to 3 show a restraint system 10 for a vehicle, in particular a passenger vehicle.

The restraint system 10 comprises at least one airbag 12 which is movable from a stowage position not shown in the figures into at least one restraint position shown in Figs. ito 5. For example, the airbag 12 is flexible and made of a material or film. As can be seen from Fig. 2, a gas storage chamber 14 is bounded by the airbag 12 in the restraint position. In the restraint position the gas storage chamber 14 is filled with a gas which can be, for example, air. The airbag 12 serves for cushioning, and, thus restraining at least one passenger of the vehicle, the passenger being also referred to as "occupant".

The restraint system 10 further comprises a plurality of volume elements in the form of hollow tubular tethers 16, 18 and 20. The tethers 16, 18, 20 are movable from a respective stowage position into at least one use position shown in Fig. 2. In the use position the respective hollow tethers 16, 18, 20 bound gas storage chambers 21, 22 and 24. In the use position which coincides with the restraint position of the airbag 12 the gas chambers 21, 22 and 24 are filled with a gas. The tubular tethers 16, 18, 20 are flexible and inflatable. By inflating the tubular tethers 16, 18, 20 the tethers 16, 18, 20 are moved from the stowage position into the use position.

As can be seen from Fig. 2 a predeterminable external shape of the airbag 12 is effected by means of the tethers 16, 18, 20. For this purpose the tethers 16, 18, 20 have different lengths so that the airbag 12 is forced into a shape which is different from an external circular shape in the restraint position.

The restraint system 10 further comprises an inflating device 26 for inflating the tethers 16, 18, 20 thereby moving the tethers 16, 18, 20 from the stowage position into the use position. Additionally, the inflating device 26 can serve for filling the airbag 12 with a gas.

Alternatively or additionally, the airbag 12 or the gas storage chamber 14 can be filled with a gas in the form of air from the interior of the vehicle by at least one external vane with at least one through opening through which air from the interior of the vehicle can flow into the gas storage chamber 14 when the airbag 12 is moved from the stowage position into the restraint position. For example, the airbag 12 is movable from the stowage position into the restraint position by moving the tethers 16, 18, 20 from the stowage position into the use position. When the airbag 12 is moved from the stowage position into the restraint position by the tethers 16, 18, 20 a low pressure is effected in the airbag 12. Due to the low pressure in the gas storage chamber 14 air from the interior is sucked into the gas storage chamber 14 through the external vent so that the gas storage chamber 14 is filled with air.

As can be seen from Fig. 2, the tethers 16, 18, 20 have internal vents 28 through which gas from the gas storage chamber 14 can flow into the gas storage chambers 21, 22 and 24 or vice versa.

The vehicle comprises at least one sensor not shown in the figures, the sensor being configured to detect a crash of the vehicle. For example, the sensor is configured to detect a frontal impact crash and/or a side impact of the vehicle. The sensor provides at least one signal characterizing the detected crash. The restraint system 10 comprises at least one control unit not shown in the figures, the control unit configured to receive the signal provided by the sensor. If the control unit receives said signal the control unit provides an activating signal which is received by the inflating device 26. As a consequence of receiving the activating signal the inflating device 26 is activated so that at least one of the tethers 20, 22, 24 is inflated. The inflating device 26 is configured as a gas generator designed to eject a gas for inflating the tethers 20, 22 and 24.

Moreover, the inflating device 26 is configured as a multi-stage inflating device capable of inflating the tethers 20, 22 and 24 in at least two consecutive stages respectively.

Moreover, the inflating device 26 is configured to inflate the tethers 20, 22 and 24 independently from each other in dependency on the signal provided by the sensor, the signal characterizing the crash. Preferably, the signal characterizes the type of the crash.

Thereby, the tethers 16, 18, 20 or at least some of the tethers 16, 18,20 can be inflated in dependency on the type of the crash. For example, in the event of a first type of crash, the tethers 16 and 18 are inflated by means of the inflating device 26 while the tether 20 is not inflated. Moreover, in the event of a second type of crash which is different from the first type of crash all tethers 16, 18, 20 are inflated. Thus, the shape and the position of the airbag 12 can be adjusted in dependency on the type of the crash since the shape and the position of the airbag 12 in the restraint position is effected by the tethers 16, 18, 20.

The restraint system 10 can be used for any type of crash such as but not limited to frontal impact crashes, side impacts, rear crashes, roll over and oblique crashes.

Moreover, the restraint system 10 can be preferably used during small overlap impact crashes. The restraint system 10 has a particularly good adaptability for high and low speed impacts. Moreover, the restraint system 10 can be used for any type of occupant with respect to size, location and kinematics. By inflating the tethers 16, 18, 20 in multiple-stages and independently from each other, the behaviour of the airbag 12 and the tethers 16, 18, 20 with respect to the inflation characteristics, the vents, the shape and the size can be controlled during the crash.

It is possible to control the behaviour of the airbag 12 dynamically during a crash based on occupant kinematics data. Furthermore, it is possible to adapt the deployment, size and shape of the airbag 12 before the crash based on data provided by the sensor. As a consequence, the danger of injuries can be kept particularly low.

The tethers 16, 18, 20 control the gas flow and the shape of the airbag 12. Thus, by controlling the inflation of the tethers 16, 18, 20, the tethers 16, 18, 20 and, thus, the airbag 12 can be deployed in a pre-determinable shape. The inflating device 26 can have multiple inflators providing divided gas flows indicated by directional arrows 30, the gas flows serving for independently inflating the tethers 16, 18, 20. The tubular tethers 16, 18, in combination with said inflators help attain different shapes of the airbag 12 to protect the occupant.

Figs. 4 and 5 show the airbag 12 having a possible shape effected by the tethers 16, 18, 20. As can be seen from Fig. 4, at least one of the tethers 16, 18, 20 can be arranged outside the airbag 12 with respect to the restrained position and the used position. In a further embodiment the tethers 16, 18, 20 are arranged inside the airbag 12 or the gas storage chamber 14 with respect to the restrained position and the used position.

List of reference signs restraint system 12 airbag 14 gas storage chamber 16 tether 18 tether tether 21 gas storage chamber 22 gas storage chamber 24 gas storage chamber 26 inflating device 28 internal vent directional arrow

Claims (6)

1. Claims A restraint system (10) for a vehicle, the restraint system (10) comprising: -at least one airbag (12) movable from a stowage position into at least one restraint position in which at least one gas storage chamber (14) is bounded by the airbag (12); -at least one inflatable volume element (16) movable from a stowage position into at least one use position in which a shape of the airbag (12) is effected by means of the volume element (16) in the restraint position of the airbag (12); and -at least one inflating device (26) for inflating the volume element (16) thereby moving the volume element (16) from the stowage position into the use position; characterized in that the inflating device (26) is configured as a multi-stage inflating device capable of inflating the volume element (16) in at least two consecutive stages.
2. 2. The restraint system (10) according to claim 1, characterized in that the volume element (16) is designed as a hollow tube.
3. 3. The restraint system (10) according to any one of claims 1 or 2, characterized in that the volume element (16) is arranged outside the airbag (12) with respect to the restraint position and the use position.
4. 4. The restraint system (10) according to any one of the preceding claims, characterized in that the restraint system (10) comprises at least one further inflatable volume element (18) movable from a stowage position into at least one use position in which the shape of the airbag (12) is effected by means of the further volume element (18), the inflating device (26) being configured to inflate the volume elements (16, 18) independently from each other and/or the further volume element (18) in at least two consecutive stages.
5. 5. The restraint system (10) according to any one of the preceding claims, characterized in that the inflating device (10) comprises at least two inflators capable of being activated independently from each other.
6. 6. A restraint system (10) for a vehicle, the restraint system (10) comprising: -at least one airbag (12) movable from a stowage position into at least one restraint position in which at least one gas storage chamber (14) is bounded by the airbag (12); -at least two inflatable volume elements (16, 18) movable from a stowage position into at least one use position in which a shape of the airbag (12) is effected by means of the volume elements (16, 18) in the restraint position of the airbag (12); and -at least one inflating device (26) for inflating the volume elements (16, 18) thereby moving the volume elements (16, 18) from the stowage position into the use position; characterized in that the inflating device (26) is configured to inflate the volume elements (16, 18) independently from each other and/or in at least two consecutive stages respectively.