Gas generator

Patent metadata

Field	Value
Publication number	US-9487183-B2
Application number	US-200913129442-A
Country	US
Kind code	B2
Filing date	Nov 26, 2009
Priority date	Dec 3, 2008
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

A gas generator ( 10 ) comprises an outer housing, which has at least two housing parts ( 12 ), which are connected to each other, in the form of a diffuser bowl ( 14 ) with outflow openings ( 16 ) towards the outside and a cover ( 20 ) directly connected to the diffuser bowl ( 14 ). Inside the gas generator ( 10 ), at least one first and one second combustion chamber ( 30, 36 ) are provided, wherein the first combustion chamber ( 30 ) is delimited by an inner wall ( 32 ) and the second combustion chamber ( 36 ) is located within the space delimited by the diffuser bowl ( 14 ) and the cover ( 20 ). The diffuser bowl ( 14 ) and/or the cover ( 20 ) comprise a section ( 24 ) that is shaped, in particular deep-drawn, into an indentation, forming at least partially a circumferential section of the inner wall ( 32 ).

First claim

The invention claimed is:

1. An inflator ( 10 ) comprising an outer housing which has at least two housing parts ( 12 ; 12 ′) connected to each other in the form of a diffuser bowl ( 14 ; 14 ′) with outflow openings ( 16 ; 16 ′) towards the outside and a cover ( 20 ; 20 ′) directly connected to the diffuser bowl ( 14 ; 14 ′), wherein inside the inflator ( 10 ) at least a first and a second combustion chamber ( 30 , 36 ; 36 ′) are provided and wherein the first combustion chamber ( 30 ) is confined by an inner wall ( 32 ; 32 ′) and the second combustion chamber ( 36 ; 36 ′) is located within the space confined by the diffuser bowl ( 14 ; 14 ′) and the cover ( 20 ; 20 ′), wherein the diffuser bowl ( 14 ; 14 ′) and/or the cover ( 20 ; 20 ′) comprise a section ( 24 ; 24 ′) that is shaped into an indentation forming at least partially a circumferential section of the inner wall ( 32 ; 32 ′) that defines the first combustion chamber ( 30 ), the section ( 24 ; 24 ′) being closed by a closing member ( 26 ; 26 ′) that further defines the first combustion chamber ( 30 ) and comprises one or more outflow openings ( 50 ).

2. The inflator according to claim 1 , wherein the first combustion chamber ( 30 ) is surrounded by the second combustion chamber ( 36 ; 36 ′) at least in sections at least in the area of the circumferential wall of the first combustion chamber ( 30 ).

3. The inflator according to claim 1 , wherein the housing parts ( 12 ; 12 ′) are shaped so that they are connected to each other along an outer closed curve ( 22 ; 22 ′) and along an inner closed curve ( 34 ; 34 ′), wherein the second combustion chamber ( 36 ; 36 ′) is formed between the outer and inner closed curves ( 22 , 34 ; 22 ′, 34 ′).

4. The inflator according to claim 3 , wherein at least one of the curves ( 22 , 34 ; 22 ′, 34 ′) have a circular shape.

5. The inflator according to claim 3 , wherein the inner wall ( 32 ; 32 ′) is mounted directly to a bottom of the opposite housing part at the inner curve ( 34 ; 34 ′).

6. The inflator according to claim 3 , wherein the housing parts ( 12 ; 12 ′) are interconnected by welding, the welds being located on the curves ( 22 , 34 ; 22 ′, 34 ′).

7. The inflator according to claim 3 , wherein the diffuser bowl ( 14 ; 14 ′) has outflow openings ( 16 ; 16 ′) for at least the second combustion chamber ( 36 ; 36 ′).

8. The inflator according to claim 1 , wherein the inner wall ( 32 ; 32 ′) is mounted directly to the bottom of an opposite housing part ( 12 ; 12 ′).

9. The inflator according to claim 1 , wherein the inner wall ( 32 ) is constituted by the shaped diffuser bowl ( 14 ).

10. The inflator according to claim 1 , wherein the closing member ( 26 ; 26 ′) forms a third housing part ( 12 ; 12 ′).

11. The inflator according to claim 1 , wherein the one or more outflow openings ( 50 ) are directed towards the outer area and/or the inner area of the inflator ( 10 ).

12. The inflator according to claim 11 , wherein the housing part ( 12 , 12 ′) provided with the indentation includes a bottom outside the indentation and the closing member ( 26 , 26 ′) is adjacent to the bottom and/or the outflow opening ( 50 ) is located in the closing member ( 26 ) substantially level with the bottom.

13. The inflator according to claim 1 , wherein respective separate outflow openings ( 50 , 16 ) are associated with the first and second combustion chambers ( 30 , 36 ).

14. The inflator according to claim 13 , wherein the outer housing has an axial central axis ( 66 ) and the outflow openings ( 50 ) of the first combustion chamber ( 30 ) are located more closely to the central axis ( 66 ) by at least the factor 2 than the second combustion chamber ( 36 ).

15. The inflator according to claim 1 , wherein the outer housing has an axial central axis ( 66 ) and the first combustion chamber ( 30 ) is arranged symmetrically with respect to the central axis ( 66 ).

16. The inflator according to claim 1 , wherein the cover ( 20 ; 20 ′) is bowl-shaped.

17. The inflator according to claim 1 , wherein the housing part ( 12 ; 12 ′) provided with the indentation is bowl-shaped and the indentation extends into the interior of the bowl.

18. The inflator according to claim 1 , wherein an igniting device ( 42 ′) associated with the second combustion chamber ( 36 ′) is arranged in a separated area ( 76 ) of the first combustion chamber.

19. The inflator according to claim 1 , wherein the first combustion chamber ( 30 ) is divided into two areas ( 76 ) independent of each other, wherein separate outflow openings ( 48 ′; 82 ) are associated with each area ( 76 ).

20. The inflator, according to claim 1 , wherein all outflow openings ( 50 ) of the first combustion chamber ( 30 ) are arranged in the outer housing such that they are located on one side of a first plane ( 72 ) including an axial central axis ( 66 ) of the outer housing.

21. The inflator according to claim 20 , wherein the outflow openings ( 50 ) arranged in the outer housing of the first combustion chamber ( 30 ) are located in a sector which is formed by the first plane ( 72 ) and a further second plane ( 74 ) including the axial central axis ( 66 ), the sector having an angle of less than or equal to 90°.

22. The inflator according to claim 20 , wherein outflow openings ( 16 ) of the second combustion chamber ( 36 ) are arranged on a third plane ( 68 ) located substantially perpendicularly to the axial central axis ( 66 ).

23. The inflator according to claim 22 , wherein the outflow openings ( 50 ) of the first combustion chamber ( 30 ) are arranged on a fourth plane ( 64 ) which is disposed substantially in parallel to the third plane ( 68 ) comprising the outflow openings ( 16 ) of the second combustion chamber ( 36 ).

24. The inflator according to claim 23 , wherein the distance between the third plane and the fourth plane ( 68 , 64 ) is between 11 and 21 mm.

25. A module comprising an inflator, an airbag inflatable by the inflator ( 10 ) and a mounting means for attaching the module, especially in the interior of a vehicle, wherein the inflator ( 10 ) is formed in accordance with claim 1 .

26. The inflator according to claim 1 , further comprising an igniting device ( 38 ; 38 ′) located at an end of the combustion chamber ( 30 ; 30 ′) opposite the closing member ( 26 ; 26 ′).

27. An inflator ( 10 ) comprising an outer housing which has at least two housing parts ( 12 ; 12 ′) connected to each other in the form of a diffuser bowl ( 14 ; 14 ′) with outflow openings ( 16 ; 16 ′) towards the outside and a cover ( 20 ; 20 ′) directly connected to the diffuser bowl ( 14 ; 14 ′), wherein inside the inflator ( 10 ) at least a first and a second combustion chamber ( 30 , 36 ; 36 ′) are provided and wherein the first combustion chamber ( 30 ) is confined by an inner wall ( 32 ; 32 ′) and the second combustion chamber ( 36 ; 36 ′) is located within the space confined by the diffuser bowl ( 14 ; 14 ′) and the cover ( 20 ; 20 ′), wherein the diffuser bowl ( 14 ; 14 ′) and/or the cover ( 20 ; 20 ′) comprise a section ( 24 ; 24 ′) that is shaped into an indentation forming at least partially a circumferential section of the inner wall ( 32 ; 32 ′), wherein the outer housing has an axial central axis ( 66 ) and the first combustion chamber ( 30 ) is arranged eccentrically with respect to the central axis ( 66 ).

Assignees

• Bierwirth Sebastian
• Cristoforetti Fabien
• Spitzenberger Dieter
• Trw Airbag Sys Gmbh

Inventors

• Bierwirth Sebastian
• Cristoforetti Fabien
• Spitzenberger Dieter

Classifications

• B60R2021/2648

  comprising a plurality of combustion chambers or sub-chambers · CPC title

• B60R21/263

  using a variable source, e.g. plural stage or controlled output (hybrid inflators B60R21/272) · CPC title

• B60R21/2644 Primary

  using only solid reacting substances, e.g. pellets, powder · CPC title

• B60R2021/2172

  the cover being connected to the surrounding part and to the module, e.g. floating mounts · CPC title

• B60R21/264

  using instantaneous generation of gas, e.g. pyrotechnic (B60R21/268 takes precedence) · CPC title