GB2341356A

GB2341356A - A seat restraint arrangement

Info

Publication number: GB2341356A
Application number: GB9920472A
Authority: GB
Inventors: Robert Anthony Corrigall; Richard James Ashmore
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1998-09-11
Filing date: 1999-09-01
Publication date: 2000-03-15
Anticipated expiration: 2019-09-01
Also published as: GB9819720D0; GB2341356B; GB9920472D0

Abstract

A seat restraint arrangement incorporated into a seat assembly of a motor vehicle comprises a barrier (7) including an inflatable tube (8) deployable between a stowed position where the tube (8) is located within the confines of the seat assembly (1) in its seat base (9) and seat back (10) to a deployed configuration where the tube (8) extends between the seat back (10) and the seat base (9). The inflatable tube (8) is of an air bag type and has tethers or net or sheet material extending from the tube to the seat assembly (1). The seat restraint arrangement when deployed provides resistance to lateral movement of seat occupants (2, 3), positioned either side of the barrier (7), during severe impacts.

Description

2341356 - 1 A SEAT RESTRAINT ARRANGEMENT The present invention relates to

a seat restraint arrangement and more particularly to a seat restraint arrangement used between a side facing seat within a motor vehicle.

Safety within a motor vehicle is of paramount concern. Thus, within motor vehicles it is common to incorporate a range of occupant restraint seat belts along with air bags and other features in order to protect the occupants from injury during severe impacts.

With regard to side facing seats, common within utility type vehicles due to their requirement for less space compared to forward facing seats, it is difficult using seat belts alone to protect occupants from the relatively violent lateral movements associated particularly with front and rear impacts. It will be understood that normal lap and crossed lapped seat belt arrangements are in principle designed to restrain forward movement of the occupant rather than lateral twist or displacement movement of the occupant within the seat. Furthermore, lateral twist movement with regard to a side facing occupant may lead to such occupants colliding with each other, etc.

One previous solution used particularly in aircraft is to provide individual netting between occupant seat cells in order to restrain such lateral movement. However, it will be appreciated with in a normal motor vehicle such netting can be inconvenient and cumbersome to install in view of the only potential necessity for such restraint during severe front or rear impacts upon the vehicle. Such netting may also need to be kept in tension 5 to be effective.

It is an object of the present invention to provide a seat restraint arrangement for a motor vehicle which substantially relieves the abovementioned problems.

In accordance with the present invention there is provided a seat restraint arrangement for side facing seating in a motor vehicle, the arrangement comprising deployable barrier means including an inflatable tube which is arranged to extend between a seat base and a seat back when deployed whilst remaining within the confines of those seat surfaces prior to deployment, said seat base and said seat back being part of a seat assembly arranged to accommodate occupants either side of the deployable barrier means whereby when deployed, these occupants engage the deployable barrier means to restrain lateral motion of those occupants across the seat assembly.

Preferably, the inflatable tube is of an air bag type deployed using a pyrotechnically generated gas or other suitable source.

Normally between the inflatable tube and the seat base and/or the seat back there is arranged a plurahty of tethers or a net or a fabric in order to ensure an effective restraint barrier is provided between occupants upon the seat assembly. These tethers or net or fabric may be reinforced using incorporated inflatable fastenings which may be coupled to an inflatable tube by inflation during deployment of the barrier means.

Typically, the inflatable tube will be coupled between the front edge of the seat base and a top edge of the seat back.

The seat assembly may be a bench seat or two seats associated together 10 with the deployable barrier means therebetween.

The seat restraint arrangement may include mounting plinths or members about the seat assembly in order to ensure an acceptable presentation for the inflatable tube and therefore the deployable barrier is provided across the seat base and the seat back.

The inflatable tube may be structured to facilitate greater resistance in particular lateral resistance through configuration, ie. undulating or through inclusion of specific structural reinforcement means such as ribs, etc.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawing, in which:

Figure 1 is a pictorial front elevation of a seat restraint arrangement deployed between two occupants of a vehicle; and Figure 2 is a pictorial front perspective of a seat belt arrangement associated with a seat assembly in a deployed configuration.

The' present invention in particular concerns a side facing seat assembly within a motor vehicle. Such side facing seat assemblies are convenient particularly with regard to so-called utility vehicles as they require less packaging space within the vehicle in comparison with front facing seats. However, as indicated above a problem with such side facing seats is that during relatively violent frontal or rear impacts any occupants seated in such a manner are thrown laterally within the seat towards each other and structural surfaces within the vehicle.

Conventional seat belt restraint arrangements are designed to restrain the occupant in a forward direction whilst the seat assembly itself will restrain rearward movement of the occupant. Clearly, it is possible to provide more elaborate multi-point set harnesses along with greater energy absorbing padding or the like about the occupant in order to protect such occupants in side facing seats. Unfortunately, such multi-point seat harnesses and provision of appropriate padding depth within a motor vehicle cabin can be cumbersome, expensive and difficult to achieve.

In accordance with the present invention a seat assembly 1 is located 5 within a motor vehicle such that occupants 2, 3 face inward of that vehicle. In the embodiment depicted in Figure 1, the seat assembly 1 is of a bench type with a mounting plinth 4 located in order to divide the seat into respective cells for each occupant 2, 3. It will be appreciated that rather than have the plinth 4, a simple surface rib or other marking could be used to denote respective cell areas for the occupants 2, 3.

The occupants 2, 3 each have a lap belt 5 which extends across the lap of that occupant 2, 3 between a mounting stem and a buckle. Such lap belts provide the occupants 2, 3 with a reasonable degree of freedom, are easy to operate and will limit movement of the occupants 2, 3 in the direction perpendicular to the drawing. Normally, any surface 6 adjacent to an occupant 2, 3 will include a reasonable degree of padding in order to protect the occupant 2, 3 during a collision. However, such padding will generally be of insufficient depth to protect an occupant 2, 3 from the full effect of a front or rear impact upon the vehicle during which the occupant 2, 3 will be thrown violently in the direction of arrow heads A rather than into or out of the page.

In order to protect the occupants 2, 3 during a severe front or rear impact, in accordance with the present invention, a deployable barrier 7 is located between these occupants 2, 3. This barrier 7 comprises an inflatable tube 8 which extends between a seat base 9 and a seat back 10 incorporating the plinth 4. However, it will also be understood that the inflatable tube 8 could also be directly coupled to this seat back 10. The barrier 7 incorporating the inflatable tube 8 thus provides an absorption depth between the occupants 2, 3 in order to keep those occupants 2, 3 separated during violent lateral motions in the direction of arrow heads A due to vehicle impacts. Typically, the inflatable tube 8 will be of an air bag type such that a pyrotechnically generated gas rapidly inflates the tube 2 in order to present the barrier 7 between the occupants 2, 3.

Clearly, for normal use having the barrier 7 between the occupants 2, 3 could be inconvenient both for movement of the occupants 2, 3 and entry or exit from the vehicle. Thus, the barrier 7 is deployable from a stowed configuration to that depicted in Figure 1 between the occupants 2, 3.

In the stowed configuration the tube 8 is deflated and retained within the cover surfaces of the seat back 10 and seat base 9. These cover surfaces include a rupture line through which the barrier is deployed. Typically, the inflatable tube 8 is secured to the seat base 9 and plinth 4 or seat back 10 through a wire or cable to ensure good retention.

In Figure 2, the seat assembly 1 is shown in pictorial front perspective with the barrier 7 deployed. Thus, the barrier 7 divides the seat assembly 1 into respective occupant cells either side with the inflatable tube 8 providing a cushion or absorption depth to protect occupants in use.

The barrier 5 is deployed through front surfaces of the seat base 9 and seat base 10 via a rupture line 11 appropriately located above the barrier when stored. In use, the barrier 7 is deployed when a sufficiently severe front or rear impact is detected such that a draw wire 12 at either end of the inflatable tube 7 is pulled whilst the tube 8 is inflated in an appropriate manner.

In the embodiment depicted in Figure 2, the plinth 4 is provided in order to ensure an appropriate angle for the inflatable tube 8 is provided to achieve the necessary protection of occupants in use. It will be understood that to ensure adequate cushion protection between occupants, that the inflatable tube 8 should at least provide a high contact point with an occupant. Thus, if the barrier 7 is coupled to the seat back 10, an insufficient contact height with an occupant may be presented.

An unfortunate consequence of such a high contact requirement between an occupants shoulder and the inflatable tube is that below this tube there may be a large free area through which particularly small occupants and children may laterally move. In order to inhibit such lateral movement as illustrated m Figure 2, straps or tethers 13 can be provided which are secured to the seat assembly 1. Rather than tethers, it will be appreciated that a net or straps or a sheet of fabric or plastics material could be located in this gap. Furthermore, these tethers or other means of filling the gap below the inflatable tube 8 could themselves be strengthened through incorporation of inflatable ribs. Such inflation may be derived from the inflatable tube 8 inflation mechanism.

p It will be appreciated that the barrier 7 must be relatively stable. 10 Thus, through the wire or cables 12 the inflatable tube 8 will be held in a taut condition in order to resist lateral movement. Such taut configuration for the barrier 7 may be achieved through mechanical mechanisms secure in the plinth 4 or seat assembly 1 via the wires or cables 12 or alternatively through inflation of the inflatable tube stimulated as it expands with tension, ie. the cables 12 are fixed to appropriate mountings such that as the inflatable tube 8 inflates and therefore radially expands the wires or cables 12 are tensioned.

In order to further enhance the robustness of the inflatable tube, it will be appreciated that this tube may include both through configuration and by addition of various structural elements, means to facilitate strength.

Thus, the inflatable tube 8 may incorporate ribs or have an undulating configuration to resist deformation.

It will be appreciated that in order for the arrangement to be effective, occupants 2, 3 of a motor vehicle should not sit astride the deployable barrier 7. In order to ensure that occupants 2, 3 do not position themselves upon the seat assembly 1 astride the stowed deployable barrier, it win be understood that the seat assembly could be made relatively uncomfortable for an occupant 2, 3 sitting in such a position through incorporation of hard ribs or outward protrusions, etc. However, most normally the location of the deployable barrier 7 will simply be marked upon the surface of the seat assembly 1 in order to ensure occupants do not inappropriately locate themselves within the vehicle upon the assembly 1.

Although it is preferred that the barrier 7 incorporates a substantially regular inflatable tube 8, it will be appreciated that this inflatable tube 8 may be configured to provide greater protection through appropriate choice of configuration. Thus, the inflatable tube 8 may present a panel outwards and inwards of the line of coupling between the seat base 9 and the back 10. Furthermore, the barrier may have a regular or irregular cross-section with an upper function of the inflatable tube, ie. adjacent occupant shoulders or head which is significantly more bulbous in comparison with that part of the inflatable tube 8 nearer the seat base 9. Irrespective of the configuration of 10- the inflatable tube 8, it will be appreciated that the rapidity of deployment for the barrier 7 must be sufficient to protect occupants 2, 3 in a vehicle impact.

As indicated above, the barrier 7 is deployed from a stowed position 5 behind a rupturable line 11 in the cover surfaces of the seat base 9 and the seat back 10. However, it will be understood that at least the following three regimes for deployment are possible in order to effect the necessary rapidity in use. The barrier 7 may be deployed by stowage in the seat base 9 with one cable 12 running in a rail up the seat back 10 rupturing the rupture line 11 as it goes, conversely the barrier 7 may be stowed in the seat back 10 and one cable 12 running in a rail located in the seat base 9 or alternatively the barrier 7 may be deployed through respective cables 12 running in rails in both the seat base 9 and the seat back 10 in order to rupture the rupture line 11 and so deploy the barrier 7.

Typically, the seat assembly 1 may include several seat restraint arrangements in accordance with the present invention to denote respective seat cells for a respective vehicle occupant.

Claims

1. A seat restraint arrangement for side facing seating in a motor vehicle, the arrangement comprising deployable barrier means including an inflatable tube which is arranged to extend between a seat base and a seat back when deployed whilst remaining within the confines of those seat surfaces prior to deployment, said seat base and said seat back being part of a seat assembly arranged to accommodate occupants so that these occupants are seated in use facing sideways to a vehicle direction of travel and either side of the deployable barrier means whereby when deployed these occupants engage the deployable barrier means to restrain lateral motion of those occupants across the seat assembly.

2. An arrangement as claimed in Claim 1, wherein the inflatable tube is an air bag deployed using pyrotechnically generated inflatable gas.

3. An arrangement as claimed in Claim 1 or Claim 2, wherein extending from the deployable barrier means there are tethers or a net or a sheet of fabric or plastics material in order to augment the engagement surface of the deployable barrier means between the inflatable tube and the seat base and the seat back.

4. An arrangement as claimed in Claim 3, wherein the tethers or nets or sheet of fabric or plastics material may be inflated with inflatable passages in order to strengthen the barrier means to restrain lateral motion of the occupants across the seat assembly.

5. An arrangement as claimed in any preceding claim, wherein the inflatable tube extends between a front edge of the seat base and a plinth or top edge of the seat back when deployed.

6. An arrangement as claimed in any preceding claim, wherein the seat assembly comprises a bench seat.

7. An arrangement as claimed in any of Claims 1 to 5, wherein the seat assembly comprises two seats associated together with the deployable barrier means arranged therebetween.

8. An arrangement as claimed in any preceding claim, wherein the seat back includes a mounting plinth arranged about a top edge of that seat back in order to ensure acceptable presentation of the inflatable tube upon deployment between the mounting plinth and the seat base of the seat assembly.

9. An arrangement as claimed in any preceding claim, wherein the inflatable tube incorporates resilient means such as an undulating configuration or structural ribs in order to provide additional resilience to the inflatable tube in use.

10. A restraint arrangement substantially as hereinbefore described with reference to the accompany drawings.

11. A motor vehicle including a seat restraint arrangement as claimed in i any preceding claim.