Gas generator for air bag and air bag apparatus

A gas generator for an air bag, comprising:

• a housing forming an outer shell container and having a gas discharge port;
• a first combustion chamber provided within said housing for accommodating first gas generating means adapted to generate a first combustion gas that exits said housing through the gas discharge port;
• a second combustion chamber isolated from said first combustion chamber and provided within said housing for accommodating second gas generating means adapted to generate a second combustion gas that exits said housing through the gas discharge port;
• first ignition means ignited, upon an impact, to burn the first gas generating means to inflate the air bag;
• second ignition means selectively ignited, upon the impact, to burn the second gas generating means to inflate the air bag;
• a coolant member provided inside said housing and adapted to pass the first combustion gas and the second combustion gas therethrough;
• and
• a flow passage forming member that forms, within said housing, a passage that passes only the second combustion gas until the second combustion gas enters said coolant member.

A gas generator for an air bag, comprising:

• a housing forming an outer shell container;
• a first combustion chamber provided within said housing for accommodating first gas generating means;
• a second combustion chamber for accommodating second gas generating means that starts burning later than the first gas generating means, said second combustion chamber being provided within said housing and partitioned from said first combustion chamber;
• first ignition means ignited, upon an impact, to burn the first gas generating means to inflate the air bag;
• second ignition means selectively ignited, upon the impact, to burn the second gas generating means to inflate the air bag;
• sealing means attached to a gas discharge port for maintaining an internal pressure of the housing to a given pressure;
• and
• a passage forming member provided within said housing and forming a first passage that passes a first combustion gas generated in the first combustion chamber and a second passage that passes a second combustion gas generated in the second combustion chamber, the first combustion gas and the second combustion gas exit the housing through the gas discharge port common to the first combustion gas and the second combustion gas,
• wherein the first combustion chamber surrounds the second combustion chamber with respect to a radial direction of said housing, and said passage forming members are provided such that a first side of the passage forming members define said first combustion chamber and a second side of the passage forming members define a passage for the second combustion gas.

A gas generator for an air bag, comprising;

• a housing forming an outer shell container including a top plate and a circumferential outer wall connected to the top plate and provided with first and second gas discharge ports, said housing including therein a first combustion chamber and a second combustion chamber provided with first gas generating means and second gas generating means, respectively;
• first ignition means ignited, upon an impact, to burn the first gas generating means to generate a first combustion gas;
• second ignition means being selectively ignited, upon the impact, to burn the second gas generating means to generate a second combustion gas;
• sealing means for closing the first and second gas discharge ports to maintain an internal pressure of the housing to a given pressure;
• a wall partitioning the first combustion chamber and the second combustion chamber, said wall having a communication hole that communicates said first combustion chamber with said second combustion chamber;
• and
• a cover opposing only the communication hole and vicinity thereof at the side of the first combustion chamber while exposing other portions of said wall such that the first gas generating means make a direct contact with the other portions of said wall and for deflecting the second combustion gas discharged from the second combustion chamber through the communication hole towards the top plate.