PRELIMINARY FASTENER FOR TIGHTENING SEAT BELT

摘要

PURPOSE: A preliminary fastener for a seat belt is provided to have a piston drive for tightening a car safety belt. CONSTITUTION: The preliminary fastener is composed of:a piston typed driving member(3) arranged inside a guide tube(2); a driving device(7) generating driving gas that drives the driving member by the expansion inside a pressure and expansion chamber that are stipulated by the driving member; motion delivering systems(4,11) combining the driving member and the seat belt to be tightened; and a releasing or a bursting element(26,40) opening a discharging orifice(37) inside the driving member while returning the driving member advanced by the driving gas.