Gas generator

A gas generator comprising:

• a gas generating agent that generates gas by burning;
• an igniter including an ignition portion loaded with an ignition agent and a terminal pin connected to the ignition portion;
• a substantially cylindrical cup with bottom where the gas generating agent is accommodated, the cup having one axial end constructed as an open end;
• and
• a substantially columnar holder that closes the open end by coaxial assembly of the cup and holds the igniter such that the ignition portion faces the gas generating agent, wherein
• the holder includes
• a first recessed portion provided in an axial end surface on a side facing the cup, where the igniter is to be received and held,
• a second recessed portion provided in an axial end surface on a side not facing the cup, where the terminal pin is to be arranged and a connector for external connection of the igniter through the terminal pin is to be received and held,
• a partition portion that serves as a partition between the first recessed portion and the second recessed portion by defining a bottom surface of the first recessed portion and a bottom surface of the second recessed portion, and
• an annular groove provided in the axial end surface on the side facing the cup, where an opening edge of the cup inserted along an axial direction is to be received and held,
• as the bottom surface of the first recessed portion has a stepped shape, the bottom surface of the first recessed portion has an annular first bottom surface located on an outer side when viewed along an axial direction of the holder and a second bottom surface located on an inner side of the first bottom surface and located on a side of the second recessed portion relative to the first bottom surface, and
• the gas generator satisfies a condition of A<B<C, where A represents a distance from the second bottom surface to the bottom surface of the second recessed portion, B represents a distance from the first bottom surface to the bottom surface of the second recessed portion, and C represents a distance from the bottom surface of the second recessed portion to the annular groove.