Patent ID: 8684413
Filing Date: 2014-04-01
Classification: B60R

Abstract:
1. A pretensioning device for a motor vehicle safety belt system comprising a gas generator, a piston guided in a tube, which closes a pressure area in the tube that is pressurized by gas from the gas generator with a pressure wherein the piston is able to move in a pretensioning movement within the tube for tensioning the safety belt system by means of movement of an inertia body resting on a front face of the piston, the piston forming a pass-through opening releasable for flow of the gas therethrough upon exceeding of a predetermined pressure in the pressure area while blocking the flow when the pressure is below the predetermined pressure in the pressure area, and the piston further forming at least one recess in the front face, forming a flow connection from the pass-through opening to an area located axially between the piston and the inertia body while the inertia body contacts the front face.