Patent ID: 6260782
Filing Date: 2001-07-17
Classification: B60R

Abstract:
A seat belt retractor comprising a spool mounted on a spool shaft for rotation in the retractor,a length of seat belt webbing wound on the spool for retraction or pay-out depending on the rotation direction of the spool;means for locking the spool shaft against rotation when a crash condition is sensed;force limiting means for allowing further pay-out of the seat belt webbing after the spool shaft has locked, under the influence of an occupant's forward momentum in the crash condition,wherein the force limiting means is provided by a plurality of fins provided on the outer surface of the spool, each fin having a section which extends in a generally radial direction and a section which extends circumferentially, the circumferentially extending section of one fin overlapping the circumferentially extending section of an adjacent fin and are supported by the radial extending section of that adjacent fin, so that a force tending to tighten the webbing on the spool, acts in a direction to crush the radial sections of the fins and to slide the circumferential sections over each other, thus reducing the effective outer circumference of the spool.