Gas generator for air bags and air bag device

摘要

The present invention provides a gas generator for an air bag in which safety and reliability are improved. Even when a gas generating agent 9a inside a first combustion chamber 5a is burnt, a gas generating agent 9b is prevented from being burnt by function of a metal thin plate 11 closing a communication hole 10 with a second combustion chamber 5b. A cup 1190 having a hole 1191 is covered on an igniter 1112, and the flame thereof advances into a transfer charge 1116 straightly in a narrow width. Accordingly, since the transfer charge 1116 is burnt completely, sufficient flame for burning a gas generating agent 1109 can be generated securely. An igniter and a transfer charge are stored in an ignition means accommodating chamber 2008, and the charge density of a transfer charge 2016a inside a transfer charge accommodating chamber 2015a is in the range of 0.1 to 5 g/cm<3>. A communication hole 3010 between a first combustion chamber 3005a and a second combustion chamber 3005b is closed by double- layered seal tape 3011 laminated through an adhesive layer. After activation, the seal tapes 3011 are not ruptured due to increase in the internal pressure of the first combustion chamber 3005a, but they are peeled off easily due to increase in the internal pressure of the second combustion chamber 3005b.