GB2341358A

GB2341358A - A seat belt having an expandable shoulder portion

Info

Publication number: GB2341358A
Application number: GB9920506A
Authority: GB
Inventors: Robert Anthony Corrigall; Richard James Ashmore
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1998-09-10
Filing date: 1999-09-01
Publication date: 2000-03-15
Anticipated expiration: 2019-09-01
Also published as: GB9819630D0; GB2341358B; GB9920506D0

Abstract

A seat belt has a shoulder portion (5, 15, 25) which may be expanded into a bulged configuration such that the seat belt is tensioned and the bulged configuration provides support to an occupant's head and neck during vehicle impacts. The seat belt is principally used with regard to side facing seats used within utility motor vehicles. The shoulder portion (5, 15, 25) may be bulged or inflated through air bag mechanisms or, alternatively, manually, upon detection of a vehicle impact.

Description

2341358 - 1 A SEAT BELT The present invention relates to a seat belt and

more particularly to a seat belt used with regard to side facing seating in a so-called off road or utility vehicle.

Provision of seat belts within a modern motor vehicle has become relatively commonplace. Such seat belts protect occupants of that vehicle during collisions. Traditionally, seat belts have comprised of simple webbing arranged to resiliently engage an occupant to restrain that occupant during a violent deceleration associated with a vehicle collision.

It is also known to provide seat belts which incorporate air bag sections which inflate during collisions. Such air bag sections broaden the belt engagement with an occupant and so diminish any prospect of injury as a result of a belt restraining the occupant over a narrower engagement area.

Unfortunately, the traditional cross-lapped and harness type seat belt arrangements are principally designed to restrain an occupant during forward collisions. Thus, with regard to occupants sitting in side facing seats typical of utility or off road vehicles or during side impacts, such conventional seat belt designs can be less effective than desired.

It will be understood, during side assaults upon a vehicle occupant that the occupant's head in particular will be subject to a violent sidewards whip motion towards one of their shoulders. Such whiplash can cause severe injury. Furthermore, continuous travel across rough ground when sitting in a sideward facing seat can continuously jar an occupant with the result that that occupant may feel at least uncomfortable.

It is an object of the present invention to provide a seat belt for a motor vehicle occupant which substantially relieves the above-mentioned problems.

In accordance with a present invention, there is provided a seat belt for a motor vehicle occupant, the seat belt arranged to engage a shoulder of that occupant through a shoulder portion and that shoulder portion including expansive means to render the shoulder portion bulged when required such that said bulged shoulder portion will provide an effective 15 energy absorption cushion between that occupant's shoulder and head.

The expansive means may be an air bag located within the shoulder portion or a manually inflatable bladder located within the shoulder portion inflated through a mouth tube.

Dependent upon the occupant's location within the vehicle, the seat belt may include a single diagonal belt incorporating the shoulder portion or two crossed diagonal belts with respective shoulder portions arranged to cross about the occupant's chest. The point of crossing of two diagonal belts can be in association with a cross adjuster arranged to vary the height of diagonal belt cross over and therefore presentation of the shoulder portions to the occupant.

The shoulder portions may comprise a plurality of individually inflatable segments. These individual inflatable segments may be selectively inflated or sequentially inflated or respectively variably inflated in order to provide the most effective energy absorption cushion between the occupant's shoulder and head.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawing, in which two embodiments of the present invention are illustrated in pictorial front elevation, a first embodiment comprises a single diagonal belt whilst a second embodiment comprises two crossed diagonal belts.

As indicated above, the present invention has particular applicability with regard to the side facing seats typical within a utility vehicle. It win be understood that within utility vehicles such side facing seats generally occupy less space than forward facing seats and so are more acceptable for occasional use. Unfortunately, such side facing seats present unconventional forces to an occupant sitting in such a seat during a collision. In particular, that occupants head is whipped towards their 5 shoulder and this may precipitate injury.

In accordance with the present invention, a seat belt includes a shoulder portion which expands into a bulged configuration in order to provide an effective energy absorption cushion between that occupant's head and shoulder. Thus, as depicted in the drawing, two embodiments of the invention are illustrated in pictorial front elevation. These embodiments are depicted as A and B. In embodiment A, an occupant 1 is located in a side facing seat 2 with a seat belt arrangement comprising a lap belt 3 and a diagonal seat belt 4. This diagonal seat belt 4 includes a shoulder portion 5 arranged to engage a shoulder of the occupant 1.

The shoulder portion 5 has a bulged cross-section as a result of expansion by appropriate means. Thus, the bulged configuration shoulder portion 5 may be inflated as an air bag during detection of a severe front or rear impact such that that occupant 1 is thrown sideways, ie. in the direction of vehicle motion shown by arrow heads Z.

Alternatively, the bulged shoulder portion 5 could be inflated manually or comprise a combination of air bag and manually inflated mechanisms. It will be understood that a ftirther particular feature of the shoulder portion 5 is that as it is inflated during an air bag deployment, then the belt 4 is 5 tensioned into closer engagement with the occupant 1.

The purpose of a bulged configuration for the shoulder portion 5 is to provide an energy absorption cushion between the occupant's shoulder and head. Thus, during a violent front or rear impact, the occupant's head is engaged by the shoulder portion 5 and gradually decelerated against the whipping force precipitated by such impact.

In embodiment A a single diagonal belt 4 is provided so that only one shoulder of the occupant 1 is engaged by the belt 4. In such circumstances, any adjacent handle, panel or post 6 of the motor vehicle on the opposite side to the belt 4 must be appropriately padded or otherwise associated with energy absorption materials in order that the occupant 1 head, if whipped by the impact forces towards that handle, panel or post 6 is appropriately engaged thereby for energy absorption and so less injury. Only then is a single diagonal belt 4 generally acceptable. However, as illustrated in embodiment B, when an occupant 11 is not near such a panel or post or these are not paddled then it is more appropriate to provide a four point or cross-belted arrangement to engage the occupant's 11 head either side and with either shoulder.

Clearly, a so-called three-point seat belt arrangement as depicted in embodiment A is less complicated in terms of mounting within a motor vehicle and for the occupant 1 to appropriately secure themselves within the seating 2 than embodiment B and therefore may be more convenient where appropriate or acceptable.

In embodiment B, as indicated above, two diagonal belts 40, 24 are arranged in a diagonal configuration across the chest of an occupant 10 with a lap belt 13 secured appropriately across that occupant's 10 lap. The diagonal belts 14, 24 present respective shoulder portions 15, 25 to the occupant 10. Thus, as with regard to embodiment A, these shoulder portions 15, 25 have a bulged configuration such that the occupant 10 when these portions 15, 25 are in their bulged configuration has an energy absorption cushion either side of their head. The shoulder portions 15, 25 may be deployed in a similar manner with regard to shoulder portions 5 of embodiment A.

With shoulder portions 15, 25 either side of the occupants 10 head, it will be appreciated that whip deflection of that head as a result of impact is limited. Furthermore, as the bulge configuration of respective shoulder portions 15, 25 is deployed, the seat belt arrangement is tensioned to more resiliently retain the occupant 10 in the seat 2.

It will be appreciated with regard to cross diagonal belts 14, 25 that conveniently a cross adjuster 17 can be located at the position where the belts 15, 25 cross but this may add to buckle connection assembly difficulties for the occupant. Thus, through appropriate adjustment of this cross adjuster 17, the orientation and angle of presentation of each shoulder portion 15, 25 to the occupant 10 may be varied. In such circumstances, the seat belt arrangement comprising the lap belt 13 and diagonal belts 14, 24 10 may be adjusted to suit an appropriate occupant 10, ie. adult or child, etc. Furthermore, it will be understood that this cross adjuster 17 may comprise a buckle secured to one portion of the seat belt arrangement such that each diagonal belt 14, 24 is divided into two with respective halves coupled to that adjuster 17.

The present invention provides a bulged configuration for the shoulder portion 5; 15, 25 but the degree of bulging provided may be adjustable to accommodate various occupant sizes and requirements along with expected vehicle activity and severity of impact. Thus, as indicated above these shoulder portions 5, 15,25 may be bulged through a combination of initial 20 padding and/or manual inflation through a mouth tube or similar means (not shown) and finally through pyrotechnically generated inflation gas presentation dependent upon detection of a vehicle impact. However, the principal objective of the present invention is to provide the occupant 1, 10 protection during violent impact and so normally the diagonal belts 4; 14, 24 will be of a normal dimension with the bulged configuration in the shoulder 5 portions 5, 15, 25 only deployed when a violent vehicle impact is detected.

Provision of manual inflation and padding may be incorporated within the diagonal belts 4; 14, 24 in order to ameliorate occupant 1, 10 discomfort and jostling within the vehicle as a result of travel over uneven road surfaces. In such circumstances, appropriate padding will be secured in a 10suitable manner to the shoulder portions of the diagonal belts 5, 15, 25 through quilting or other technique.

For manual inflation, a separate bladder will be provided within the shoulder portions 5; 15, 25 from any air bag inflation mechanism. This separate bladder may be inflated through a mouth tube or appropriate pumping mechanism which may be manual or electrically operated.

Clearly, occupant 1; 10 comfort and protection is of paramount importance with regard to a seat belt. Thus, it will be appreciated that the shoulder sections 5; 15, 25 may incorporate separately inflatable segments to potentially irregularly inflate these shoulder portions 5; 15; 25. In such 20circumstances it will be appreciated that the shoulder portions 5; 15, 25 may be transiently and/or irregularly inflated in accordance with occupant 1; 10 differences in terms of size and preference along with different vehicle impact scenarios. Thus, these independently inflatable segments of the shoulder portions 5; 15, 25 may be inflated selectively and/or consecutively and/or variably in order to embrace the occupant 1; 10 both in terms of reciprocal shaping to that occupant 1; 10 along with sympathetic inflation or mechanical tensioning dependent upon the present occupant 1; 10. Furthermore, it will be appreciated that the effective operational length, depth and width of the inflatable shoulder portions 5; 15, 25 may be varied in order to provide optimum restraint both initially and through the vehicle impact episode.

It will also be appreciated that through the appropriate bulge configuration of the shoulder portions 5; 15, 25 during vehicle impact that the potential aggressive engagement between a relatively sharp normal seat belt web edge into an occupant's 1; 10 neck is dirnini h d.

Provision of expansion of the shoulder portions 5; 15, 25 into the bulged configurations necessary in accordance with the present invention can be achieved through provision of a tubed seat belt with an inflatable air bag within that tube. Thus, in normal use, the seat belt tube will be appropriately configured with concertina or folded side walls such that a substantially flat seat belt is provided to the occupant 1; 10 whilst upon deployment, and so expansion in the air bag, the concertina or folds in the seat belt web are unravelled to produce the bulged configuration necessary to support the occupant 1, 10 along with tensioning of the seat belt.

It will be understood that within the seat belt tube, as indicated previously, a manually inflatable bladder could be incorporated to provide a degree of occupant 1, 10 protection from normal vehicle travel jostling. Furthermore, the belt, as also indicated previously, could include passive padding to again provide a degree of normal travel jostle protection.

a As indicated previously, it is convenient with regard to the present 10 invention if the seat belt is adaptable in terms of the degree and range of the bulged configuration. Thus, it will be appreciated that restrainer members could be secured to the seat belt in order to limit the extent of inflation into the bulged configuration. These restrainer members would be appropriately anchored to the diagonal belts 4, 14, 24 at the height the occupant 1; 10 required. In such circumstances, the volume of gas deployed will be more accurately presented to those portions of the shoulder portion 5; 15, 25 necessary to provide the occupant 1; 10 with protection. In such circumstances, the bulged configuration will thereby generally be more rapidly achieved and the localised bulging of the bulged configuration will be greater for a unit period of time.

These restrainer members may have a permanent or a transient effect upon deployment. Clearly, a permanent retainer member will restrain the bulge configuration in terms of seat belt length whilst a transient retainer member will act for an appropriate period of time in order to protect the occupant as quickly as possible by ensuring air bag deployment gases are only or preferentially presented to those parts of the shoulder portion 5, 15, 25 providing most significant protection to the occupant 1, 10. It will be appreciated that the adjuster 17 could constitute a retainer member limiting further bulge deployment of the diagonal seat belts 14, 24.

A final feature with regard to the present seat belt is that it will be appreciated within some utility vehicles occupants are closely seated in inwardly side facing seats. Thus, in addition to injuries as a result of head whiplash, it will be understood that adjacent occupants may clash heads. Thus, the present shoulder portions should achieve sufficient bulge configuration to either prevent or dimini h the violence of such head clashing to an extent that injury is reduced. Furthermore, it will be appreciated that, with regard to shoulder portions between adjacent occupants, that a greater degree of bulging may be provided in comparison with shoulder portions which are not. Furthermore, the degree of bulging between shoulder portions in a crossed diagonal belt configuration, ie. embodiment B may be such that there is asymmetric bulging between respective shoulder portions in the same seat belt arrangement in order to account for such adjacent occupant head clashing.

Claims

-13CLAIMS 1. A seat belt for a side-facing motor vehicle occupant, the seat belt including at least one belt being arranged to engage a shoulder of that occupant through a shoulder portion and that shoulder portion including expansive means to render that shoulder portion specifically bulged compared to the other parts of the seat belt when required, such that said bulged shoulder portion will provide an effective cushion between that occupant's shoulder and head against lateral motion.

1

2. A seat belt as claimed in Claim 1, wherein the expansive means is an air bag arrangement appropriately deployed when a vehicle impact is detected.

3. A seat belt as claimed in Claim 1 or Claim 2, wherein the expansive means includes a manually inflatable bladder which may expand the shoulder portion into a bulged configuration in order to inhibit occupant jostle.

4. A seat belt as claimed in Claim 1 or Claim 2, wherein the seat belt comprises two belts in a diagonal crossed configuration.

5. A seat belt as claimed in Claim 4, wherein the diagonal cross seat belts have a cross adjuster located where these respective belts cross about an occupant.

6. A seat belt as claimed in Claim 4 or Claim 5, wherein respective shoulder portions in each seat belt are rendered through the expansive means to have an asymmetric bulged configuration between respective occupant's shoulders.

7. A seat belt as claimed in any preceding claim, wherein the shoulder portion includes independently inflatable segments respectively rendered bulged by the expansive means.

8. A seat belt as claimed in Claim 7, wherein each independently inflatable segment may be selective bulged by the expansive means.

9. A seat belt as claimed in Claim 7 or 8, wherein the independently inflatable segments may be rendered bulged by the expansive means sequentially.

10. A seat belt as claimed in Claim 7 or 8 or 9, wherein each independently inflatable segment may be rendered bulged by the expansive mean to a variable degree.

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11. A seat belt as claimed in any preceding claim, wherein the seat belt includes retainer members arranged to limit the degree that the shoulder portion is rendered bulged by the expansive means.

12. A seat belt substantially as hereinbefore described with reference to the drawings with regard to embodiment A.

13. A seat belt substantially as hereinbefore described with reference to the accompanying drawings with regard to embodiment B. i

14. A motor vehicle including a seat belt as claimed in any preceding claim.