Multi-stage ignition type gas generator

• US 20040244632A1
• Filed: 06/02/2004
• Published: 12/09/2004
• 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
• Granted Patent: US 7,150,227 B2
• Time in Patent Office: Days
• US Class Current: 102/530
• 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. 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, in a housing having a gas discharge port, 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 at least one of the first combustion chamber and the second combustion chamber passes before reaching the gas discharge port, wherein the first combustion chamber and the third combustion chamber, and the second combustion chamber and the third combustion chamber are defined by a partition wall respectively, and, in both partition walls, 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, in all of the combustion chambers, a gas generating agent burnt to generate a gas is disposed respectively, and the gas generating agent disposed in the first combustion chamber and the gas generating agent disposed in the second combustion chamber 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, and further, a first ignition means directly igniting and burning the gas generating agent is disposed in the first combustion chamber and a second ignition means directly igniting and burning the gas generating agent is disposed in the second combustion chamber.

2. The multi-stage ignition type gas generator as claimed in claim 1, wherein a communicating port is formed in at least one of the partition wall defining the first combustion chamber and the third combustion chamber and the partition wall defining the second combustion chamber and the third combustion chamber, and a restriction means is arranged from the third combustion chamber side on all the communicating ports.

3. The multi-stage ignition type gas generator as claimed in claim 2, wherein at least one of the restriction means arranged on the communicating port is a member which conducts one or more of deformation, destruction by fire, detachment, displacement, rupture and break only by the combustion of the gas generating agent in the combustion chamber defined in a partition wall provided with the communicating port , and opens the communicating port.

4. The multi-stage ignition type gas generator as claimed in claim 3, wherein at least one of the restriction means arranged on the communicating port is selected independently from a metal tape, a cover and a check valve closing the communicating port.

5. The multi-stage ignition type gas generator as claimed in claim 2, wherein at least one of the restriction means arranged on the communicating ports is a member having a portion facing the communicating port and diverting the gas released from the combustion chamber defined inside a partition wall provided with the communicating ports.

6. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein a bent portion projecting to the third combustion chamber side is formed in at least one of the partition wall defining the first combustion chamber and the third combustion chamber and the partition wall defining the second combustion chamber and the third combustion chamber, and at least one of the restriction means formed in both partition walls is a fragile portion formed in this bent portion, and wherein the fragile portion opens only by the combustion of the gas generating agent in the combustion chamber defined inside the partition wall provided with the fragile portion, and produces the communicating port.

7. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein in at least one of the partition wall defining the first combustion chamber and third combustion chamber and the partition wall defining the second combustion chamber and third combustion chamber, a shielding means, which prevents direct contact between a restriction means arranged in the partition wall and a gas generating agent, is arranged.

8. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein the third combustion chamber is formed by a housing, the first combustion chamber and the second combustion chamber are inside the third combustion chamber, they are distributed in one side of the housing axial direction, and the first ignition means and the second ignition means are installed on the end portion of the side in which the first combustion chamber and the second combustion chamber are distributed in one side in the housing.

9. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein the third combustion chamber is formed by a housing, the first combustion chamber is inside the third combustion chamber with being defined on one end side of the housing axial direction, the second combustion chamber is inside the third combustion chamber with being defined on other end side of the housing axial direction, and the first ignition means and the second ignition means are installed on either end portion of the housing axial direction.

10. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein the first combustion chamber, third combustion chamber and the second combustion chamber are next to each other in the axial direction in a housing by this order, a first ignition means is arranged on the end portion of the side in which the first combustion chamber exists in the housing axial direction, and a second ignition means is arranged on the end portion of the side in which the second combustion chamber exists in the housing axial direction.

11. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein the first ignition means and the second ignition means comprises an igniter for initiating operation of the gas generator, and the igniter included in the first ignition means and the igniter included in the second ignition means are build into a single common igniter collar to be installed to the housing.

12. The multi-stage ignition type gas generator as claimed in claim 1 or 2, wherein a coolant, through which all the gases advancing to a gas discharge port pass, is disposed in the third combustion chamber.