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.
According to the invention there is provided head and neck restraint apparatus for an occupant of a vehicle, the apparatus comprising:
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.
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
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
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
Referring now specifically to
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
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
As best indicated in
Number | Date | Country | Kind |
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2007/02327 | Mar 2007 | ZA | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IB2008/051037 | 3/19/2008 | WO | 00 | 5/27/2010 |