GB2262720A

GB2262720A - Combined air bag and seat belt safety device

Info

Publication number: GB2262720A
Application number: GB9226971A
Authority: GB
Inventors: Ah Yew Soh
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-12-24
Filing date: 1992-12-24
Publication date: 1993-06-30
Anticipated expiration: 2012-12-24
Also published as: GB2262720B; GB9226971D0; GB9127362D0

Abstract

A safety device 13 for a vehicle 3 comprises an inflatable cushion 25 releasably attached to a seat belt 7 by a zip fastener. The safety device also comprises a trigger device which includes a container 26 filled with compressed gas and a detonator 26a. The detonator 26a is activated in response to movement of the seat belt 7. The container 26 could also be filled with a volatile propellant or even a small explosive device. <IMAGE>

Description

SAFETY DEVICE The present invention relates to a device for protecting drivers or passengers of vehicles from injury in the event of an accident.

The most common means for protection against injuries in motor vehicles is the seat belt. However, during a crash, the body can still undergo violent movement as it is restrained by the belt. Injuries can still result from the belt itself and from sharp acceleration and deceleration experienced by the human frame. Moreover, the driver is not protected if, as a result of a frontal collision, the steering column is pushed into the cabin with the weight of the engine behind it.

A number of elaborate systems have been proposed for cushioning drivers or passengers against the forces and objects which cause injuries as a result of collisions.

However, these are complicated, expensive to manufacture, at in at least one case, preferably should be built into the car when it is manufactured.

In particular, there have been proposals for inflatable bags arranged to be activated by abnormal tensioning or other behaviour of a vehicle seatbelt as a result of an accident. These are described in GB-A-1 332 051 and US-A-4 258 931. An analogous system wherein the seat belt itself is caused to inflate is described in US-A-3 877 719.

All these known seat belt triggered arrangements are complicated. They have to be pre-fitted to the seat belt during manufacture, and in some cases, require the seat belt to be fabricated with special features for enabling the safety device to operate correctly.

A novel device has now been devised which can afford useful protection during accidents, is relatively inexpensive to manufacture and can easily be installed in all kinds of motor vehicle, even if the vehicle was not manufactured with such a device already fitted.

Thus, the present invention provides a safety device for a vehicle, the safety device comprising an inflatable cushioning means, a trigger device for causing the cushioning means to inflate, means for operating the trigger device in response to the movement of a seat belt of the vehicle in the event of an accident and fitment means for enabling a user to fit the safety device to the seat belt.

The fitment means may be any for enabling the user to fit the safety device to his or her own car for example fastening means such as Velcro (Trade Mark) or a zip-fastener or a clamp.

Most preferably, the fitment means is a releasable fitment means enabling the user to remove the safety device when required. Thus, for example, the fitment means may comprise two parts. A first such part may be provided for permanent or semi-permanent attachment to the seat belt. A second part may be provided for releasably attaching the remainder of the safety device to the seat belt. Preferably, the first and second parts allow repeated attachment and disengagement of the safety device.

For example, the first part may be adapted to be stitched, secured by adhesive, riveted, clamped or attached by any suitable means to the seat belt. The second means may comprise any suitable releasable fastening such as a zip-fastener, velcro, a releasable clamp or the like.

The possibility of removing the safety device means that it can rapidly be detatched, for example if accidentally triggered, so that the driver can continue to drive. Of course, when required it can also be attached very quickly. The safety device is well suited to use in the back seats of automobiles.

For the avoidance of doubt, reference herein to attachment of the safety device by the fitment means, should be taken to include attachment to any part of the seatbelt such as an anchor point, roller mechanism, buckle or the belt itself.

The fitment means may connect the safety device by any part thereof, including the cushioning means (or a container for same), the trigger device or the trigger device operating means. One or more other parts of the safety device may also be attached to a different part of the seat belt or even to another part of the vehicle.

Conveniently the device is mounted direct on the seat belt, preferably in such a position that it will be directly above the lap of the wearer when in use, ie.

approximately at a position one third along the length of the seat belt from the bottom thereof.

Preferably, the trigger device comprises a container, eg. a capsule or cannister, of a compressed gas such as carbon dioxide. However, it could also comprise a container filled with a volatile propellant or even a small explosive device, since a large volume of gas is normally released as the result of a chemical explosion.

The means for operating the trigger device may for example comprise a cord. If the device is fitted direct to the seat belt, then conveniently, the cord extends between the trigger device and the buckle of the seat belt. The cord could equally extend between the trigger device and a fixed part of the vehicle interior, eg. the body or the seat itself.

Yet again, the device could be attached to such a fixed part of the vehicle interior and the cord would then extend between the trigger device and part of the seat belt, for example, the buckle.

The device should be positioned such that in use, in the event of an accident, the cushion will inflate and extend in such a direction as to protect the wearer from injury.

The present invention will now be explained in more detail by the following description of a preferred embodiment and with reference to the accompanying drawings, in which Figure 1 shows a safety device according to the present invention, before use; Figure 2 shows the safety device shown in Figure 1, after activation; Figure 3 shows how the safety device shown in Figure 1 is attached to a car seat belt; and Figure 4 shows further details of the safety device shown in Figure 1.

As shown in Figure 1, a passenger 1 in a motor vehicle 3 is seated in the normal driving position in a seat 5.

The driver is protected by a seat belt 7 which extends between a lower fixed part (anchor point) 9 and an upper fixed part (anchor point) 11 both attached to the inside of the vehicle. A safety device 13 according to the present invention is attached to the lower part 15 of the seat belt.

As seen more clearly in Figure 2, the device 13 is attached to the belt by a detachable fastening in the form of a zip fastener (not shown). One half of the fastner is semi-permanently or permanently attached to the belt by stitching 17. In Figure 2, the lower point of attachment 9 is shown to one side of the seat for purposes of clarity. The belt is provided with a buckle having a slot 21 through which the belt passes so that the buckle is freely slidable along the length of the belt. In use, the buckle is inserted into a snap-fit clasp 23. The latter is shown in phantom since it is on the far side of the seat.

The safety device comprises a deflated inflatable cushion 25 in a bag and a cylinder 26 of carbon dioxide with an associated detonator 26a. The triggering mechanism is attached to one end 27 of a cord 29, the lower portion 30 of which is inside the bag. The cylinder, detonator and lower part 30 of the cord are shown in phantom because they are hidden inside the cushion bag. The other end 31 of the cord 29 is loosely attached to the buckle.

In use, the belt is arranged around the body of the driver or passenger in the normal way and fastened by insertion of the buckle into the clasp. When it is in place, the cord 29 is lightly tensioned between the safety device and the buckle.

In the event of an impact, the wearer will be thrown forward beyond the limit of the cord. Since the buckle is freely slidable along the belt, the resulting relative movement will pull on the cord which its turn activates the trigger mechanism. As a result, carbon dioxide gas will rapidly fill the cushion.

The cushion 25 is so arranged that upon inflation, it rises in front of the wearer as shown in Figure 3. The cushion is dimensioned so that it does not obscure the vision of the driver when in this inflated state so that if possible, the driver can continue to drive safely.

In this way, the wearer is protected from injury by the steering column 33 or other part of the vehicle interior.

Referring now to Figure 4, additional details of the safety device are shown. The cushion 25 is shown in its deflated but unfurled slate. It measures 31 cm in width (parallel to the cord) and 51. 5 cm in length (perpendicular to the cord). Releasable attachment to the seatbelt is permitted by virtue of the zip-fastener 35.

The free ends 37, 39 of the cord 29, 30 are provided with respective releasable attachment means 41, 43 in the form of a clip or hook for attachment to the anchor points 9, 11.

In the light of this disclosure, persons skilled in the art will now be able to envisage modifications of the described embodiment as well as other embodiments, all within the scope of the present invention as hereinbefore defined.

Claims

1. A safety device for a vehicle, the safety device comprising an inflatable cushioning means, a trigger device for causing the cushioning means to inflate, means for operating the trigger device in response to the movement of a seat belt of the vehicle in the event of an accident and fitment means for enabling a user to fit the safety device to the seat belt.

2. A safety device according to claim 1, wherein the fitment means is adapted to permit releasable attachment of the safety device to the seat belt.

3. A safety device according to claim 1 or claim 2, wherein the fitment means comprises two parts.

4. A safety device according to any of claims 1-3, wherein the fitment means comprises a zip fastener.

5. A safety device according to any preceding claim, wherein the trigger device comprises a container of a compressed gas.

6. A safety device according to any of claims 1 to 4, wherein the trigger device comprises a container filled with a volatile propellant.

7. A safety device according to any of claims 1 to 4, wherein the trigger device comprises an explosive device.

8. A safety device according to any preceding claim, when fitted to a seat belt.

9. A safety device according to any preceding claim, wherein the means for operating the trigger device comprises a cord.

10. A safety device according to claim 9 when dependent on claim 8, wherein the cord extends between the trigger device and a buckle of the seat belt.

11. A safety device according to claim 9, when dependent on claim 8, wherein the cord extends between the trigger device and a fixed part of the vehicle interior.

12. A safety device according to claim 9, attached to a fixed part of the vehicle interior, and extending between the trigger device and part of the seat belt.

13. A safety device for a vehicle, the safety device being substantially as hereinbefore described with reference to the accompanying drawings.