Gas generator

A gas generator comprising:

• a housing having an elongated cylindrical shape extending in an axial direction and including, inside of the housing,
• an activation gas generation chamber in which an activation gas is generated by combustion of a gas generating agent, and
• a filter chamber in which a filter through which the activation gas generated in the activation gas generation chamber passes is accommodated;
• a gas generating agent ignition unit that encloses an ignition charge, is disposed at one end in the axial direction of the housing, and allows the gas generating agent to be ignited and combusted in the activation gas generation chamber;
• and
• a holder fixed to the one end in the axial direction of the housing and including
• a first holder portion having a substantially tubular shape and defining a keeper that keeps the gas generating agent ignition unit on an inner side of the housing, and
• a second holder portion having a substantially tubular shape, integrally provided with the first forming portion on a side of the first holder portion opposite to the activation gas generation chamber, and defining a connector fitting portion configured to be fitted with a connector for energizing the gas generating agent ignition unit on an opposite side of a keeping position of the gas generating agent ignition unit;
• and
• a side surface cover that is a bottomed tubular member defining a tubular cover portion,
• wherein the side surface cover is configured to cover at least a part of the gas generating agent ignition unit facing the activation gas generation chamber and at least a part of a side surface of the first holder portion,
• in a radial direction perpendicular to the axial direction of the housing, the tubular cover portion is sandwiched between an inner wall of the housing and the side surface of the first holder portion to form radially overlapping portions of the housing, the tubular cover portion, and the side surface of the first holder portion which overlap each other in the radial direction, and
• the radially overlapping portions of the housing, the tubular cover portion, and the side surface of the first holder portion are fixed together by an annular welding fixation extending annularly along a circumferential direction of the housing.