Gas generator

• US 7,338,074 B2
• Filed: 12/15/2003
• Issued: 03/04/2008
• 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: Schönhuber, Georg, Inman, Reed
• Primary Examiner(s): Dickson; Paul N.
• Assistant Examiner(s): Brown; Drew J.
• Application Number:
  US10/736,146
• Publication Number:
  US 20040124618A1
• Time in Patent Office: 1,541 Days
• Field of Search: 280/742, 280/741, 280/736, 102/530, 102/531
• US Class Current: 280/742
• 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 from said cover wall (30) 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, wherein said igniter chamber (12) contains a propellant charge (32).

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

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

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

9. The gas generator according to claim 1, wherein 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, wherein 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, wherein 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).

12. The gas generator according to claim 1 wherein said cap (22) is configured to be free of fracturing during displacement along said inner wall (14).

13. The gas generator according to claim 1 wherein said first section (26) extends in a direction away from said igniter (16) and terminates at a location downstream from said cover wall (30).

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),

wherein 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, wherein at least one of said first and second sections (26, 28) at least partially is realized so as to be double-walled.

15. 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),

wherein 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, wherein 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.

16. The gas generator according to claim 15, wherein in said double-walled region of said peripheral wall (24) an inner wall section lies against an outer wall section.

17. 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 (22) having a cylindrical peripheral wall (24) and a radially extending cover wall (30), wherein said cover wall (30) is turned axially into an interior of said cap (22) so that the cover wall (30) extends for at least half of a height (h) of the cap (22) into the interior of the cap (22), the degree of turning in of the cap (22) defining the volume of the igniter chamber (22).

18. The gas generator according to claim 17, wherein 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).

19. The gas generator according to claim 17, 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.

20. The gas generator according to claim 17, wherein 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).

21. The gas generator according to claim 17 wherein said cap (22) is configured to be free of fracturing during displacement along said inner wall (14).

22. 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 cover wall (30) connected with one end of the peripheral wall, wherein said cover wall (30) is turned axially into an interior of said cap (22) and the cap (22) is inserted into the igniter chamber (12) so that the cover wall (30) is at least partially positioned between a free end of the peripheral wall (24) and the igniter (16).