Belt pretensioner

A pretensioner for a three point vehicle safety restraint seat belt, comprising a mounting for one end of the seat belt, the mounting comprising a first member fixed to a load bearing part of the vehicle and a second member attached to the end of the seat belt, and means for moving the second member relative to the first member in a pretensioning direction in response to activation of a crash sensor.The mounting may be a slide bar or a flexible cable. A piston-cylinder force reservoir may be used either to pull the slider bar via a carriage mounted on a rail, or to pull the cable directly. Return motion is preferably inhibited.The arrangement provides a space saving venatile pretensioner suitable for two-door vehicles whilst allowing access to the vehicle rear.