Patent ID: 7681915

Claim:
A gas generator for an airbag comprising: an elongated cylindrical tube comprising metal, the tube including a first closed end and second end; a partitioning plate which partitions an inside of the tube, in an axial direction, into a combustion chamber packed with gas generant which is burnable to generate high pressure gas, and a hollow cylindrical filter chamber fitted with a filter material; an igniter, fitted at the second end of the tube, that ignites and burns the gas generant in the combustion chamber; and a holder which closes the second end of the tube and holds the igniter, wherein the partitioning plate comprises a metal higher in hardness than that of the tube, wherein the tube includes a crimped portion on its peripheral face at locations adjacent to the partitioning plate, wherein plastic deformation of the crimped portion creates, on the inside face of the tube, a depressed portion which reduces a plate thickness of the tube such that the partitioning plate bites 0.1 mm or more into a wall of the tube from a peripheral edge face of the partitioning plate, wherein the partitioning plate has a first thickness portion and a second thickness portion, which is smaller in thickness than the first thickness portion and is a leading end of a portion that bites into the wall of the tube, and wherein the partitioning plate is tapered from the first thickness portion to the second thickness portion, so that the thickness of the partitioning plate decreases toward the second thickness portion.