Gas generator

• US 6,886,338 B2
• Filed: 06/09/2004
• Issued: 05/03/2005
• Est. Priority Date: 06/27/2003
• Status: Expired due to Fees

• Current Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Gabler, Michael, Fischer, Joachim, Hofmann, Achim
• Primary Examiner(s): NGUYEN, HOANG M
• Application Number:
  US10/864,213
• Publication Number:
  US 20040261409A1
• Time in Patent Office: 328 Days
• Field of Search: 606/32, 606/37, 606/38, 280/736, 280/737, 280/741, 280/742
• US Class Current: 60/632
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 21/26 characterised by the inflation fluid source or means to control inflation fluid flow arrangement or mounting thereof to the vehicle B60R21/20; blasting cartridges for producing gas under pressure in general F42B3/04; initiators or igniters therefor F42B3/10
• CPC Class Codes: B60R 21/261 with means other than bag structure to diffuse or guide inflation fluid
• CPC Class Codes: B60R 21/264 using instantaneous generation of gas, e.g. pyrotechnic B60R21/268 takes precedence
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators
• CPC Class Codes: F16K 7/02 with tubular diaphragm

Abstract

A gas generator comprises an outflow chamber and a freeing element. The outflow chamber contains at least briefly gas under pressure, when the gas generator is activated and at least one outflow opening is arranged in a side wall of the outflow chamber. The freeing element is arranged non-displaceably in the outflow chamber and has a peripheral wall and a base wall. The peripheral wall extends along the side wall and closes at least one outflow opening before an activation of the gas generator. The base wall is connected with the peripheral wall. The freeing element is constructed so that on exceeding a predetermined gas pressure in the outflow chamber, the base wall turns inwards under partial plastic deformation of the peripheral wall and at least one hitherto concealed outflow opening is freed by the plastic deformation of the peripheral wall.

Claims

1. A gas generator comprising:

an outflow chamber (14) and

a freeing element (24),

said outflow chamber (14) containing at least briefly gas under pressure, when said gas generator (10) is activated and

at least one outflow opening (20) being arranged in a side wall (18) of said outflow chamber (14),

said freeing element (24) being arranged non-displaceably in said outflow chamber (14),

said freeing element (24) having a peripheral wall (26) and a base wall (28),

said peripheral wall (26) extending along said side wall (18), closing at least one outflow opening (20) before an activation of said gas generator (10), and circumscribing an interior of said feeing element (24),

said base wall (28) being connected with said peripheral wall (26) and

said freeing element (24) being constructed so that on exceeding a predetermined gas pressure (p) in said outflow chamber (14), said base wall (28) turns inwards and is moved within or into said interior of said freeing element (24) under partial plastic deformation of said peripheral wall (26) and at least one hitherto concealed outflow opening (20) is freed by said plastic deformation of said peripheral wall (26).

2. The gas generator according to claim 1, wherein, with said plastic deformation of said freeing element (24), a length of said peripheral wall (26) along said side wall (18) is shortened.

3. The gas generator according to claim 1, wherein said base wall (28) is constructed in one piece with said peripheral wall (26).

4. The gas generator according to claim 1, wherein said freeing element (24) is formed in a single piece.

5. The gas generator according to claim 1, wherein, already before an activation of said gas generator (10), said base wall (28) is partially turned inwards into said peripheral wall (26) forming an indentation (30) and said indentation (30) deepens on exceeding said predetermined gas pressure (p).

6. The gas generator according to claim 1, wherein before activation of said gas generator (10), said base wall (28) continues at an angle of 180 degrees into said peripheral wall (26).

7. The gas generator according to claim 1, wherein said peripheral wall (26) is tubular.

8. The gas generator according to claim 1, wherein said peripheral wall (26) is ring-shaped.

9. The gas generator according to claim 1, wherein said peripheral wall (26) lies under tension against an inner side of said side wall (18) of said outflow chamber (14).

10. The gas generator according to claim 1, wherein several outflow openings (20) are provided, arranged one behind the other in axial direction (A) of said outflow chamber (14), said outflow openings (20) being freed successively through said plastic deformation of said freeing element (24).

11. The gas generator according to claim 1, wherein before said activation of said gas generator (10) at least one outflow opening (20) of said outflow chamber (14) is not closed by said peripheral wall (26).

12. The gas generator according to claim 1, wherein said gas generator (10) contains compressed gas.