Gas generator for air bag

• US 20050200107A1
• Filed: 01/13/2005
• Published: 09/15/2005
• Est. Priority Date: 01/15/2004
• Status: Active Grant

• Current Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Original Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Inventors: Matsuda, Naoki, Hirooka, Masato
• Granted Patent: US 7,665,764 B2
• Time in Patent Office: Days
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

The gas generator includes, a housing having a gas discharge port, a first combustion chamber defined by the housing, a first gas generating agent adapted to generate gas to inflate an air bag, the first gas generating agent having a first combustion temperature and disposed in the first combustion chamber, a second gas generating agent adapted to generate gas to inflate the air bag, the second gas generating agent having a second combustion temperature lower than the first combustion temperature and disposed in the first combustion chamber, and a first ignition unit for directly igniting at least one of the first gas generating agent and the second gas generating agent.

Claims

1. A gas generator comprising a housing having a gas discharge port, ignition means for starting an operation of the gas generator and a gas generating agent that generates gas by being ignited and burned in order to inflate an air bag and at least one combustion chamber defined in the housing, the gas generating agent being placed in at least one combustion chamber, at least two types of gas generating agents having different combustion temperatures from each other being placed in at least one of the at least one combustion chamber.

12. The gas generator for an air bag as claimed in claim 1, including one, two or three combustion chambers.

2. A gas generator, comprising:

a housing having a gas discharge port;

a first combustion chamber defined by the housing;

a first gas generating agent adapted to generate gas to inflate an air bag, the first gas generating agent having a first combustion temperature and disposed in the first combustion chamber;

a second gas generating agent adapted to generate gas to inflate the air bag, the second gas generating agent having a second combustion temperature lower than the first combustion temperature and disposed in the first combustion chamber; and

first ignition means for directly igniting at least one of the first gas generating agent and the second gas generating agent.

3. The gas generator for an air bag as claimed in claim 2, wherein the first gas generating agent is charged in an amount that enables the second gas generating agent to be ignited and burned by combustion of the first gas generating agent.

4. The gas generator for an air bag as claimed in claim 2, further comprising:

a partition member, having a communication hole, provided inside the first combustion chamber for separating the first gas generating agent and the second gas generating agent inside the first combustion chamber.

5. The gas generator for an air bag as claimed in claim 4, wherein the partitioning member partitions the interior of the first combustion chamber in relation to the amount of first gas generating agent and the second gas generating agent charged in the first combustion chamber.

6. The gas generator for an air bag as claimed in claim 3, further comprising:

a second combustion chamber defined within the housing;

a third combustion chamber defined within the housing;

a third gas generating agent adapted to generate gas to inflate the air bag, the third gas generating agent having a third combustion temperature and disposed in the second combustion chamber;

a fourth gas generating agent adapted to generate gas to inflate the air bag, the fourth gas generating agent having a fourth combustion temperature lower than the third combustion temperature and disposed in the second combustion chamber; and

second ignition means for directly igniting at least one of the third gas generating agent and the fourth gas generating agent.

7. The gas generator for an air bag as claimed in claim 2 or 3, wherein the first ignition means includes only an electric igniter ignited by applying an operating current, and the first gas generating agent is ignited directly by an activation of the electric igniter.

8. The gas generator for an air bag as claimed in claim 2 or 3, wherein the first combustion temperature is between 1700 and 3000°

C., and the second combustion temperature is between 1000 and 1700°

C.

9. The gas generator for an air bag as claimed in claim 6, wherein the third combustion temperature is between 1700 and 3000°

C., and the fourth combustion temperature is between 1000 and 1700°

C.

10. The gas generator for an air bag as claimed in claim 4, further comprising:

an inner cylinder provided inside the housing and extending between a diffuser shell and a closure shell of the housing,

wherein the partition member is a part of the inner cylinder.

11. The gas generator for an air bag as claimed in claim 2, wherein

the first gas generating agent has a non-perforated shape and the second gas generating agent has a single-perforated cylindrical shape.