Patent ID: 8070085
Filing Date: 2011-12-06
Classification: B21C,B21J,B21K,B60R

Abstract:
1. A pretensioner, comprising: a gas generation unit that is activated to generate gas; a cylinder that is formed into a cylindrical shape open at both ends, has the gas generation unit mounted thereto from one of the open ends, and is supplied with gas generated by the gas generation unit to the inside of the cylinder so that an internal pressure of the cylinder is increased, the cylinder having a high-strength portion that extends from an inner circumferential portion of the cylinder toward the center of the cylinder at a predetermined position between the one of the open ends and the other of the open ends such that a wall thickness of the cylinder is enlarged at the predetermined position; and a tension adding unit that is moved within the cylinder by gas pressure provided by the gas generation unit so as to increase a tension of a webbing belt configuring a seatbelt device, wherein the high-strength portion is formed near a gas blowing section of the gas generation unit through which gas is blown into the cylinder, the outer circumferential shape of the cylinder has the same shape from one of the open ends to the other of the open ends, and the cylinder is molded by the forging of molding material.