Abstract: A gas generator includes a housing and an igniter assembly defining, together with the housing, an accommodating space in which a gas source is stored. The igniter assembly includes an igniter, a collar member, a resin member integrally joining the igniter and the collar member, and a cover member made of metal, surrounding an ignition portion and the resin member in a manner that the igniter and the resin member are sealed with respect to the accommodating space, and configured to be ruptured when the igniter is actuated. The cover member is welded to the collar member over an entire circumference while straddling a boundary line between the resin member and the collar member.

Abstract: An electric circuit breaker device includes a housing enclosing an accommodating space, an igniter, and a conductor piece. The housing includes a housing body that holds the conductor piece and a top housing portion provided with the igniter. The top housing portion forms, by the top housing portion being attached to a first surface of the housing body, an internal space communicating with the accommodating space and forming an end of the accommodating space, and includes a peripheral wall that defines an outer periphery of the accommodating space and is provided along the extending direction of the accommodating space, a top-side flange portion extended from a contact portion of the peripheral wall with the first surface toward an outer side of the top housing portion along the first surface, and a rib portion extended along the extending direction from an outer side edge of the top-side flange portion.