APPARATUS FOR PRETENSIONING A VEHICULAR SEAT BELT

摘要

A pretensioning apparatus for a vehicular seat belt includes a housing (128), a tube (134) extending from the housing (128) and defining an inner surface, a piston (148) disposed within the tube (134) in close proximity to the inner surface of the tube (134), a cable (144) connected at a first end to the piston (148) and at a second end to the seat belt, and lock members (160) disposed between the piston (148) and the inner surface of the tube (134). Upon application of force to the piston (148) in a first direction, the lock members (160) permit free movement of the piston (148), and upon application of force to the piston (148) in a second direction, the lock members (160) engage the inner surface of the tube (134) to prevent movement of the piston (148).