Patent ID: 8720944
Filing Date: 2014-05-13
Classification: B60R

Abstract:
1. A gas generator for a restraining device of a vehicle comprising: a housing forming an outer shell container of the gas generator, and having a circumferential wall portion which is provided with a gas discharge port, a first end, and a second end, opposite to the first end, the first end and the second end being both closed; a cup-shaped inner tube member disposed in the housing so that an opening end portion thereof is located in a side of a bottom plate of the second end, an inside of the cup-shaped inner tube member being an ignition chamber accommodating an ignition device, an outer space of the cup-shaped inner tube member being a combustion chamber charged with a gas generating agent, the inner tube member defining an inner circumferential surface of the combustion chamber; an annular porous member defining an upper surface of the combustion chamber and being provided such that a space is formed between the annular porous member and the bottom plate of the first end of the housing, the annular porous member having a plurality of holes that allows communication between the combustion chamber and the space, a gas passage extending in a radial direction of the housing and defined by a concave surface and a convex surface disposed in the space such that an inner circumferential of the concave surface and the convex surface is placed with a distance from the cup-shaped member; a step portion defining a gas discharge path connecting the space and gas discharge port; a communicating portion communicating the space and the gas discharge path and being open prior to activation of the gas generator; and a total cross-sectional area of the gas discharge port being smaller than a total opening area of the plurality of holes of the annular porous member; a cross-sectional area of the communicating portion; and a cross-sectional area of the space.