Gas generator

• US 20040124618A1
• Filed: 12/15/2003
• Published: 07/01/2004
• Est. Priority Date: 12/23/2002
• Status: Active Grant

• Current Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Schonhuber, Georg, Inman, Reed
• Granted Patent: US 7,338,074 B2
• Time in Patent Office: Days
• US Class Current: 280/736
• 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 gas generator includes a housing having an inner wall delimiting an igniter chamber peripherally, and at least one igniter opening into the igniter chamber. The gas generator further includes a cap arranged for displacement along the inner wall and delimiting the igniter chambe, said cap having a cylindrical peripheral wall and a radially extending cover wall. The peripheral wall has a first section extending from the cover wall in displacement direction (R) and a second section extending in a direction opposite thereto. The first and second sections lie against the inner wall and guide the cap during a displacement thereof. The cover wall is turned axially into the interior of the cap.

Claims

1. A gas generator, comprising

a housing having an inner wall (14) delimiting an igniter chamber (12) peripherally,

at least one igniter (16) opening into said igniter chamber (12), and

a cap (22) arranged for displacement along said inner wall (14) and delimiting said igniter chamber (12), said cap having a cylindrical peripheral wall (24) and a radially extending cover wall (30),

characterized in that said peripheral wall (24) has a first section (26) extending from said cover wall (30) in a displacement direction (R) and a second section (28) extending in a direction opposite thereto,

said first and second sections (26, 28) lying against said inner wall (14) and guiding said cap (22) during a displacement thereof.

2. The gas generator according to claim 1, characterized in that said igniter chamber (12) contains a propellant charge (32).

3. The gas generator according to claim 1, characterized in that said first and second sections (26, 28) are cylindrical and have the same external diameter.

4. The gas generator according to claim 1, characterized in that an axial length of said first section (26) corresponds approximately to an axial length of said second section (28).

5. The gas generator according to claim 1, characterized in that at least said first section (26) lies against said inner wall (14) under prestress.

6. The gas generator according to claim 1, characterized in that said first section (26) strikes against a housing part of said gas generator (10) at an end of said displacement.

7. The gas generator according to claim 6, characterized in that said first section (26) is constructed so as to have such a rigidity that it is not plastically deformed at said end of said displacement.

8. The gas generator according to claim 1, characterized in that said first and second sections (26, 28) continue into each other in one piece.

9. The gas generator according to claim 1, characterized in that said peripheral wall (24) and said cover wall (30) are connected with each other in one piece.

10. The gas generator according to claim 1, characterized in that said cap (22) is a one-piece sheet metal shaped part, said peripheral wall (24) and said cover wall (30) being formed by deformation of said sheet metal shaped part.

11. The gas generator according to claim 1, characterized in that at least one of said first and second sections (26, 28) at least partially is realized so as to be double-walled.

12. The gas generator according to claim 1, characterized in that said peripheral wall (24) is partially turned into an interior of said cap (22) by plastic axial drawing of said cover wall (30), and is constructed so as to be double-walled in said turned-in region.

13. The gas generator according to claim 12, characterized in that in said double-walled region of said peripheral wall (24) an inner wall section lies against an outer wall section.

18. The gas generator according to claim 1, characterized in that said inner wall (14) includes at least one outflow opening (18) of said igniter chamber (12) and said cap (22) is constructed such that, before activation of said gas generator (10), it covers said outflow opening (18) and, during said activation of said gas generator (10) and said displacement of said cap (22), it opens said outflow opening (18).

14. A gas generator comprising a housing having an inner wall (14) delimiting an igniter chamber (12) peripherally, at least one igniter (16) opening into said igniter chamber (12), and a cap (22) arranged for displacement along said inner wall (14) and delimiting said igniter chamber (12), said cap having a cylindrical peripheral wall (24) and a radially extending cover wall (30), characterized in that said cover wall (30) is turned axially into an interior of said cap (22).

15. The gas generator according to claim 14, characterized in that an axial edge (211) of said peripheral wall (24), facing away from said igniter (16), strikes against a housing part of said gas generator (10) at an end of a displacement of said cap (22).

16. The gas generator according to claim 14, characterized in that said cap (22) is a one-piece sheet metal shaped part, said peripheral wall (24) and said cover wall (30) being formed by deformation of said sheet metal shaped part.

17. The gas generator according to claim 14, characterized in that said inner wall (14) includes at least one outflow opening (18) of said igniter chamber (12) and said cap (22) is constructed such that, before activation of said gas generator (10), it covers said outflow opening (18) and, during said activation of said gas generator (10) and a displacement of said cap (22), it opens said outflow opening (18).