Method for locking and load limiting of a seat belt

摘要

A pretensioner usable with a seat belt to protect an occupant from injury comprising: a cable (40), movable in a belt tightening direction and in a belt loosening direction connected to the seat belt so that motion of the cable causes movement of the seat belt; a piston (112) for moving the cable and the belt a determinable amount in the tightening direction; a wedge housing (22) and wedges (30a, b) responsive to the motion of the cable in both the belt tightening direction for releasing the cable and responsive to motion of the cable in the loosening direction for locking upon the cable to prevent same from moving in the presence of a predetermined force applied to the belt.