ADAPTIVE HEAD AND NECK RESTRAINT SYSTEM FOR A VEHICLE OCCUPANT

Abstract

Head and neck restraint apparatus for an occupant of a vehicle comprises a stiff yoke shaped to engage the upper torso and shoulders of the occupant. The yoke is generally U-shaped, with a base and upwardly extending limbs, and has a frontal portion shaped to extend over the chest of the occupant which corresponds to the base of the U. An intermediate portion of the yoke is shaped to fit over the shoulders of the occupant, and an upper portion of the yoke, corresponding to the upper ends of the limbs, extends beyond the intermediate portion to constrain movement of a helmet worn by the occupant. A set of first guides on the yoke are arranged to engage harness members of a safety harness worn by the occupant. Each guide is shaped to engage a respective harness strap or buckle and responds to longitudinal movement of the harness strap or buckle. Tensioning members connected between the respective guides and the helmet apply a tensioning force to the helmet when movement of the occupant causes displacement of the harness relative to the yoke. A set of second guides that respond to lateral movement of the harness is also provided.

Description

BACKGROUND OF THE INVENTION

THIS invention relates to a head and neck restraint system for an occupant of a vehicle.

The occupant of a vehicle such as a high performance motor racing vehicle, a high speed power boat or the like is subjected to significant accelerations, particularly in the event of a crash. Occupants of such vehicles generally wear a crash helmet and a four- or six-point harness securing them in position in a seat.

Various systems have been proposed for enhancing the protection offered to the occupant of such a vehicle by tethering the occupant's helmet to a support structure of some kind. For example, it has been proposed to provide a yoke which rests on the upper torso of the occupant, to which the helmet is tethered. The purpose of such devices is to limit the movement of the helmet and hence the head and neck of the occupant relative to the occupant's torso when substantial accelerations are experienced, particularly in a crash.

It is an object of the invention to provide alternative head and neck restraint apparatus.

SUMMARY OF THE INVENTION

According to the invention there is provided head and neck restraint apparatus for an occupant of a vehicle, the apparatus comprising:

• • a stiff yoke shaped to engage the upper torso and shoulders of the occupant, the yoke having a frontal portion shaped to extend over the chest of the occupant, an intermediate portion shaped to fit over the shoulders of the occupant, and an upper, helmet engaging portion extending beyond the intermediate portion and shaped to constrain movement of a helmet worn by the occupant;
  • a plurality of first guide means associated with the yoke and arranged to engage harness members of a safety harness worn by the occupant, each guide means being shaped to engage a respective harness member and being responsive to longitudinal movement of said harness member relative to said guide means; and
  • a plurality of tensioning members connectable between the respective guide means and the helmet,
    so that movement of the occupant causing displacement of the harness relative to the yoke results in a tensioning force being applied to the helmet by at least one tensioning member.

The yoke is preferably generally U-shaped, with a base and upwardly extending limbs, the base of the U corresponding to the frontal portion of the yoke and the upper ends of the limbs corresponding to the helmet engaging portion thereof.

A pair of first guide means are preferably mounted on the frontal portion of the yoke, each guide means being arranged to receive a respective strap of a safety harness worn by the occupant.

Preferably, each first guide means is shaped to engage a buckle or other formation on the strap so that longitudinal movement of the strap relative to the first guide means, at least in one direction, is prevented.

Preferably each first guide means is mounted slidably relative to the yoke so that an acceleration causing movement of the occupant and the yoke relative to the harness causes sliding displacement of the first guide means relative to the yoke.

The tensioning members are preferably flexible cords fixed to the first guide means at one end thereof and connectable to respective fixing points on the helmet in use.

Preferably, the yoke defines a guide for each tensioning member to ensure correct orientation thereof in use.

For example, the yoke may define conduits extending between a lower edge of the frontal portion of the yoke, adjacent to the first guide means, and respective inner surfaces of the helmet engaging portion of the yoke.

Preferably, the apparatus includes a plurality of second guide means mounted on the intermediate portion of the yoke and arranged to engage respective harness members passing over the shoulders of the occupant in use, the second guide means being responsive to lateral movement of the harness members due to movement of the occupant causing displacement of the harness relative to the yoke, with a plurality of tension members each connectable between a second guide means and the helmet.

Each second guide means is preferably mounted slidably relative to the yoke so that an acceleration causing lateral movement of the occupant and the yoke relative to the harness causes sliding displacement of the second guide means relative to the yoke.

The head and neck restraint apparatus is thus operable to constrain movement of the occupant's helmet, and thus the occupant's head and neck, relative to the occupant's torso as a result of movement of the occupant in both fore-and-aft and lateral directions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial view of head and neck restraint apparatus according to the invention;

FIG. 2 is a pictorial view similar to that of FIG. 1, showing the range of movement of first and second guide means of the apparatus;

FIG. 3 is a pictorial view similar to those of FIGS. 1 and 2, showing the straps of a harness engaged with the apparatus;

FIG. 4 is a similar illustration to that of FIG. 3, additionally showing a helmet of a user of the apparatus in position adjacent to the apparatus;

FIGS. 5 & 6 are side views showing the apparatus in use, before and after an impact;

FIG. 7 is a front view of a user of the apparatus, corresponding to FIG. 5;

FIG. 8 is a similar view to that of FIG. 7, showing the effect of a lateral impact on the user; and

FIG. 9 is a top view of the user, corresponding to FIG. 6.

DESCRIPTION OF EMBODIMENTS

FIGS. 1 and 2 show an embodiment of head and neck restraint apparatus according to the present invention. The apparatus is intended for use by occupants of vehicles, boats, aircraft and other craft or vessels that may be subject to rapid accelerations or impact in use. For purposes of this specification, the word “vehicle” is intended to refer to any and all vehicles, crafts, conveyances or the like.

The apparatus comprises a yoke 10 which is generally U-shaped and which has a frontal portion 12 corresponding to the base of the U, an intermediate portion comprising a pair of limbs 14 and 16 which generally correspond to the limbs of the U, and a pair of upper, helmet engaging portions 18 and 20 which correspond to the upper ends of the U.

The yoke 10 is preferably rigid and can be molded from a suitably strong plastics material, glass fibre and resin, or a light weight composite material comprising carbon fibre or Kevlar (trade mark), for example. It will be appreciated that the materials indicated are merely exemplary and that other suitable materials could also be used.

The yoke is shaped to rest of the shoulders of a user of the apparatus, with the frontal portion of the yoke lying over the upper torso or chest area of the user. The limbs 14 and 16 include curved shoulder engaging formations 22 and 24 which extend over and behind the shoulders of the user in use, locating the yoke firmly on the upper torso of the user. When so located, the yoke defines an opening 26 below and around the neck and head of the user. The opening 26 is sized to permit a degree of unimpeded movement of the user's neck relative to the yoke, but the width is less than the width of a conventional crash helmet worn by the user, preventing the yoke from being lifted upwardly off the user while the user is wearing the helmet.

The upstanding helmet engaging members 18 and 20 have curved inner surfaces 28 and 30 shaped complementally to the curvature of a typical crash helmet, allowing them to extend close to the crash helmet in use without impeding its movement unduly as the user moves his or her head. Thus, the user can rotate his or her head from side to side while wearing the yoke 10. The helmet restraining members 18 and 20 limit rearward movement of the helmet relative to the yoke, but permit free forward movement of the helmet.

Mounted on the body of the yoke are two pairs of guides which engage the straps of a four- or six-point harness worn by the user. A first pair of guides 32 and 34 are mounted on the frontal portion of the yoke, on its upper surface and towards opposed side edges thereof. A second pair of guides 36 and 38 are mounted on respective upper surfaces of the shoulder engaging portions 22 and 24 of the yoke.

The guides 32 and 34 each comprise a generally cruciform bracket having a pair of arms 40 and 42 extending on either side of an elongate central member 44. Outer ends 50 and 52 of the arms 40 and 42 are curved inwardly, enabling them to retain a harness strap between them in use. An elongate slot 46 extends substantially the entire length of the central member 44 and is sized to fit about the shaft of a bolt 48 fixed to the yoke so that the entire guide can slide longitudinally relative to the bolt, between the positions shown in solid and dotted outlines in FIG. 2.

The guides 36 and 38 are simpler in design, each comprising an elongate member 54 having a longitudinally extending slot 56 therein. A bolt 60 retains each guide 36, 38 slidably on the yoke, allowing it to move between the positions shown in solid and dotted outline in FIG. 2. The elongate member 54 has an inwardly curved outer end 58 at an outer end of the member 54, for retaining a harness strap in the guide.

At the lowermost ends of the guides 32 and 34, and at the innermost ends of the guides 36 and 38, attachment points 62 are provided to which are fixed respective flexible cords 64 and 66. The attachment points each define one or more holes or slots through which the cords 64 and 66 are threaded and looped to lock them in a desired position on the guides. For example, in the case of a user with a relatively long neck, the cords will be adjusted to be longer than for a user with a shorter neck.

The cords 64 attached to the guides 32 and 34 pass through respective openings 68 in the front edge of the frontal portion of the yoke 10 and through conduits or passages 70 defined in the body of the yoke, exiting at respective openings 72 in the helmet engaging surfaces 28 and 30. The cords 66 pass through respective conduits 74 and out of the same apertures 72. The exit points for the cords defined by the apertures 72 are generally at least 115 mm below and 125 mm behind the centre of gravity of the head of an average user of the apparatus seated in an upright neutral position.

The cords 64 and 66 serve as tensioning members or tethers which are fixed to attachment points on the rear side surfaces of the user's helmet in use. The cords will normally be attached to an FIA certified helmet mount or existing helmet strap which is located below and generally behind the centre of gravity of the user's head. The cords will typically be a Kevlar or Vectran (trade marks) fibrous cord, or comprise a similar suitable material, which is flexible but non-extendable under tension.

When a user is wearing the yoke and a helmet, as shown in FIG. 4, the cords 64 and 66 are attached to a helmet 76 as shown, with just sufficient play to allow normal movement of the user's head without pulling the cords tight.

Referring now specifically to FIGS. 3 and 4, the interaction between the apparatus of the invention and a safety harness worn by the user of the apparatus is shown.

The user wears a four-, five- or six-point harness including a pair of straps 78 and 80, which pass over the shoulders of the user to respective anchorages 82 in the vehicle at the upper end of the backrest 84 of a seat occupied by the user. Such a harness always has shoulder portions and lap portions and, in five- and six-point harnesses, also has one or two crotch portions. Thus, a four-point harness will comprise left and right shoulder portions and left and right lap portions making up the four points, with five- and six-point harnesses having one or two additional crotch portions, respectively.

Conventionally, such harnesses have adjustable buckles which allow the straps 78 and 80 to be adjusted snugly over the user's shoulders. In the illustrated prototype apparatus of the invention, these buckles 86 are received by the guides 32 and 34, with the straps 78 and 80 being located and retained by the inwardly curved outer ends of the arms of the guides. The upper edge of the buckle abuts the ends of the arms, preventing the buckle from moving longitudinally past the guide. The straps also pass through the guides 36 and 48 as shown in FIG. 4, being retained in position on the guides by the curved outer ends thereof.

Instead of providing guides that engage existing buckles on the harness straps, it is also possible to provide strap engaging means in the form of clamps or gripping members which are fastened to the strap at a desired location. The rollers are arranged to wind the tether cords around a reel or shaft when an impact causes the harness straps to move relative to the yoke and rotate the rollers. In such an embodiment, the harness strap will slide over the roller and the friction between the roller and harness strap will cause the roller to rotate and so wind the cord onto it, tensioning the cord.

In another embodiment, rollers can be mounted on the upper guides 36 and 38 in an integrated system in which the rollers react to longitudinal movement of the harness and lateral sliding of the guides takes place in response to lateral movement of the harness.

In the event of an impact, the torso of the user moves relative to the harness straps, typically by as much as 100 mm. The movement of the user relative to the harness in the case of a frontal impact is shown in FIGS. 6 and 9. The user's torso is displaced relative to the straps themselves, and consequently relative to the position of the harness buckles or other strap engaging means. The yoke 10 moves forward with the user's torso in this scenario, causing the strap buckles to slide upwardly, together with the respective guides 32 and 34, relative to the yoke. This pulls the cords 64 tight, exerting a pre-tensioning force in the direction of the arrow in FIG. 6. This force maintains the correct orientation of the helmet 76 and prevents the user's head from extending forwards.

As best indicated in FIGS. 7 and 8, when a lateral impact occurs, the user's torso is displaced laterally relative to the initial position of the harness straps, causing an outward displacement of one or the other of the guides 36 or 38 and tensioning the respective cord 66, thus exerting a corrective pre-tensioning force on the user's helmet and maintaining the correct alignment of the user's head and neck.

Claims

1.-11. (canceled)

12. Head and neck restraint apparatus for an occupant of a vehicle, the apparatus comprising:

a stiff yoke shaped to engage the upper torso and shoulders of the occupant, the yoke having a frontal portion shaped to extend over the chest of the occupant, an intermediate portion shaped to fit over the shoulders of the occupant, and an upper, helmet engaging portion extending beyond the intermediate portion and shaped to constrain movement of a helmet worn by the occupant;

a plurality of guide means associated with the yoke and arranged to engage harness members of a safety harness worn by the occupant, each guide means being shaped to engage a respective harness member and being responsive to movement of said harness member relative to said guide means; and

tensioning members connectable between the respective guide means and the helmet, so that movement of the occupant causing displacement of the harness relative to the yoke results in a tensioning force being applied to the helmet by at least one tensioning member.

13. The apparatus of claim 12, wherein the yoke is generally U-shaped, with a base and upwardly extending limbs, the base of the U corresponding to the frontal portion of the yoke and the upper ends of the limbs corresponding to the helmet engaging portion thereof.

14. The apparatus of claim 12, wherein said plurality of guide means comprises:

a pair of guide means mounted on the frontal portion of the yoke, each said pair of guide means being arranged to receive a respective strap of a safety harness worn by the occupant.

15. The apparatus of claim 14, wherein each of said pair of guide means is shaped to engage a formation on the strap so that longitudinal movement of the strap relative to said guide means, at least in one direction, is prevented.

16. The apparatus of claim 12, wherein each of said plurality of guide means is mounted slidably relative to the yoke so that an acceleration causing movement of the occupant and the yoke relative to the harness causes sliding displacement of said guide means relative to the yoke.

17. The apparatus of claim 12, wherein said tensioning members are flexible cords fixed to said guide means at one end thereof and connectable to respective fixing points on the helmet in use.

18. The apparatus of claim 12, wherein the yoke defines a guide for each tensioning member to ensure correct orientation thereof in use.

19. The apparatus of claim 18, wherein the yoke defines a plurality of conduits extending between a lower edge of the frontal portion of the yoke, adjacent to said guide means, and respective inner surfaces of the helmet engaging portion of the yoke.

20. The apparatus of claim 12, wherein said guide means is mounted on the intermediate portion of the yoke and arranged to engage respective harness members passing over the shoulders of the occupant in use, said guide means being responsive to movement of the harness members due to movement of the occupant causing displacement of the harness relative to the yoke, with a plurality of tension members each connectable between said guide means and the helmet.

21. The apparatus of claim 20, wherein said guide means is mounted slidably relative to the yoke so that an acceleration causing lateral movement of the occupant and the yoke relative to the harness causes sliding displacement of said guide means relative to the yoke.

22. The apparatus of claim 20, wherein the yoke defines a plurality of conduits extending between the intermediate portion of the yoke, and respective inner surfaces of the helmet engaging portion of the yoke.