Patent ID: 7665764

Claim:
A gas generator comprising: a housing having a gas discharge port; an inner cylinder provided inside the housing, the inner cylinder including a partition wall dividing the inner cylinder into an upper cylinder section and a lower cylinder section; the upper cylinder section including a partition plate dividing the upper cylinder section into an upper space at the top of the upper cylinder section above the partition plate and a lower space below the partition plate and above the partition wall; ignition means for starting an operation of the gas generator included in the lower cylinder section; a first gas generating agent being directly ignited by the ignition means, the first gas generating agent having a first combustion temperature and having a gas generating capacity such that when ignited the first gas generating agent will generate an amount of gas that is not less than 1.2 mol/100 g; a second gas generating agent being ignited only by combustion of the first gas generating agent, the second gas generating agent having a second combustion temperature lower than the first combustion temperature and having a gas generating capacity such that when ignited the second gas generating agent will generate an amount of gas that substantially contributes to inflation of the air bag; a first combustion chamber defined in the housing, the first combustion chamber accommodating, therein, only the first gas generating agent; and a second combustion chamber defined in the housing, the second combustion chamber accommodating, therein, only the second gas generating agent, and an amount of the second gas generating agent is greater than an amount of the first gas generating agent.