Multi-stage ignition type gas generator

• US 7,150,227 B2
• Filed: 06/02/2004
• Issued: 12/19/2006
• Est. Priority Date: 06/03/2003
• Status: Active Grant

• Current Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Original Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Inventors: Matsuda, Naoki
• Primary Examiner(s): JOHNSON, STEPHEN
• Application Number:
  US10/858,051
• Publication Number:
  US 20040244632A1
• Time in Patent Office: 930 Days
• Field of Search: 102/202, 280/741
• US Class Current: 102/202
• CPC Class Codes: B60R 2021/26058 using a combination of inflators
• 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

A multi-stage ignition type gas generator has a first combustion chamber and a second combustion chamber defined independently from each other, and a third combustion chamber through which a gas generated in the first combustion chamber and the second combustion chamber passes before reaching a gas discharge port. In a partition wall defining the first combustion chamber and the third combustion chamber and a partition wall defining the second combustion chamber and the third combustion chamber, a restriction means, which opens a communicating port communicating a combustion chamber and the third combustion chamber only by gas pressure generated in the combustion chamber defined inside the partition wall, is arranged, and a gas generating agent disposed in the first combustion chamber and a gas generating agent disposed in the second combustion chamber are different in at least one of all gas output and gas output per unit time.

Claims

1. A multi-stage ignition type gas generator, comprising:

a housing having a gas discharge port;

a first combustion chamber provided inside the housing;

a second combustion chamber provided inside the housing separately from the first combustion chamber;

a third combustion chamber provided inside the housing and through which a gas generated in at least one of the first combustion chamber and the second combustion chamber passes before reaching the gas discharge port;

a first partition wall separating the first combustion chamber and the third combustion chamber and defining a first communicating port that communicates the first combustion chamber and the third combustion chamber;

a second partition wall separating the second combustion chamber and the third combustion chamber and defining a second communicating port that communicates the second combustion chamber and the third combustion chamber;

first restriction means that seals the first communicating port, the first restricting means allowing communication between the first combustion chamber and the third combustion chamber only by a gas pressure generated in the first combustion chamber;

second restriction means that seals the second communicating port, the second restriction means allowing communication between the second combustion chamber and the third combustion chamber only by a gas pressure generated in the second combustion chamber;

a first gas generating agent accommodated in the first combustion chamber for generating a first combustion gas for inflating an air bag;

a second gas generating agent accommodated in the second combustion chamber for generating a second combustion gas for inflating the air bag;

a third gas generating agent accommodated in the third combustion chamber for generating a third combustion gas for inflating the air bag;

a first ignition means for directly igniting and burning the first gas generating agent;

a second ignition means for directly igniting and burning the second gas generating agent; and

shielding means, which prevents at least one of the first communication port and the second communication port from being obstructed by at least one of the first gas generating agent, the second gas generating agent, and the third gas generating agent,

wherein, the first gas generating agent and the second gas generating agent are different in at least one of combustion heat, combustion temperature, all gas output, and gas output per unit time in combustion of the gas generating agent.

2. The multi-stage ignition type gas generator as claimed in claim 1, wherein the first restriction means seals the first communicating port from the third combustion chamber side.

3. The multi-stage ignition type gas generator as claimed in claim 2, wherein the first restriction means at least one of deforms, destructed by fire, detaches from the first partition wall, displaces, ruptures, and breaks only by combustion of the first gas generating agent and opens the first communicating port.

4. The multi-stage ignition type gas generator as claimed in claim 3, wherein the first restriction means is selected from the group consisting of a metal tape, a cover, and a check valve that closes the first communicating port.

5. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein the first ignition means includes a first igniter and the second ignition means includes a second igniter for initiating operation of the gas generator, and the first igniter and the second igniter are attached to a single common igniter collar attached to the housing.

6. The multi-stage ignition type gas generator as claimed in claim 1 or 2, further comprising:

a coolant that defines the third combustion chamber therein,

wherein, the first combustion gas, the second combustion gas, and the third combustion gas pass through the coolant before being discharged from the discharge port.

7. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein the shielding means is made of one of a wire mesh and a multi-perforated plate.

8. The multi-stage ignition type gas generator as claimed in claim 1, wherein the second restriction means seals the second communicating port % from the third combustion chamber side.

9. The multi-stage ignition type gas generator as claimed in claim 1, wherein the shielding means is made of one of a wire mesh and a multi-perforated plate.