Crimp-formed joint housings for air bag inflators

• US 5,458,371 A
• Filed: 10/27/1994
• Issued: 10/17/1995
• Est. Priority Date: 10/27/1994
• Status: Expired due to Term

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Morton International Incorporated (Autoliv Incorporated)
• Inventors: Smith, Bradley W., Parker, Todd S., Hock, Christopher, Fulmer, Brian H.
• Primary Examiner(s): FERRITER, KARIN L
• Application Number:
  US08/330,344
• Time in Patent Office: 355 Days
• Field of Search: 280/736, 280/741, 280/742, 280/740, 422/164, 422/165, 422/166, 102/530, 102/531
• US Class Current: 280/741
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

An air bag inflator for generating gas to rapidly inflate an air bag includes a housing having spaced-apart opposite end walls with aligned outer peripheral edges, an outer side wall extending between the end walls around the peripheral edges defining an outer chamber for containing gas-generating material and a filter element. The housing also includes an inner side wall extending between the end walls in concentric, centered relation for containing an ignition squib and ignition-enhancing material and provided with ignition ports in communication with the other combustion chamber. The outer side wall is provided with a plurality of ports directing hot products of combustion outwardly to inflate an associated air bag. At least one pair of concentric crimp-formed joints are provided to interconnect the side walls and at least one of the end walls, top or bottom.

Claims

1. An inflator for generating gas to rapidly inflate an air bag, comprising:

a quantity of gas generating material;

housing means having spaced apart opposite end walls with aligned outer peripheral edges;

an outer side wall extending between said upper and lower end walls around said peripheral edges thereof defining an enclosure for holding an annular filter element adjacent said outer side wall and providing an annular chamber inside said filter element for holding the quantity of gas generating material;

an annular filter in said housing means adjacent an inner surface of said outer side wall for entrapping combustion residue from said gas generated in said housing means before discharge of said gas;

an inner side wall extending between said end walls in concentric centered relationship with said outer side wall defining a central ignition chamber for containing an igniter, wherein the gas generating material is held between the inner side wall and the filter element;

said inner side wall formed with a plurality of ignition ports spaced apart around the periphery thereof for directing hot ignition gases into said annular chamber for igniting the gas generating material;

said outer side wall formed with a plurality of diffusion ports spaced apart around the periphery thereof for directing gases from the gas generating material outwardly to rapidly inflate said air bag;

a pair of resilient annular sealing rings for sealing between facing interior surfaces of said opposite end walls and respective adjacent annular opposite end portions of said annular filter for preventing gas generated in said housing means from bypassing said filter to reach said diffusion ports; and

at least one crimp-formed annular flange on said outer side wall engaging at least one of said end walls for closing said housing means and compressing said sealing rings to seal said opposite end portions of said filter to seal against blow-by.

2. The inflator of claim 1, wherein:

at least one of said end walls is integrally formed with at least said outer side wall.

3. The inflator of claim 1, including:

a plurality of said crimp-formed flanges formed adjacent opposite ends of said outer side wall for respectively sealingly engaging both of said end walls.

4. The inflator of claim 1, wherein:

at least one of said end walls is joined to an adjacent end of said inner side wall in a crimp-formed joint.

5. The inflator of claim 4, including:

a plurality of said crimp-formed joints formed adjacent opposite ends of said inner side wall for respectively sealingly engaging both of said end walls.

6. The inflator of claim 4, wherein:

one end of said inner side wall is integrally formed with an adjacent end wall and an opposite end of said inner side wall is joined with an opposite end wall in a crimp-formed joint.

7. The inflator of claim 4, wherein:

one end of said inner side wall is welded to an adjacent end wall and an opposite end of said inner side wall is joined with an opposite end wall in a crimp-formed joint.

8. The inflator of claim 4, wherein:

one of said end walls is interconnected with both said inner and outer side wall with crimp-formed joints.

9. The inflator of claim 1, wherein

said inner side wall includes an integral closed end forming a central wall portion closing an opening in one of said end walls.

10. The inflator of claim 4, wherein:

one of said crimp-formed joints includes a crimped mounting ring engaging said outer side wall and said outer peripheral edge of one of said end walls.

11. A housing for an air bag inflator, comprising:

a quantity of gas generating material;

cylindrical inner and outer side walls and a pair of opposite end walls joined therewith to form a sealed enclosure;

said inner side wall forming a central ignition chamber for containing ignition means and having a plurality of gas ports in communication with a gas generation chamber holding the gas generation material around said ignition chamber;

said outer side wall having a plurality of gas exit ports for discharging gas generated in said gas generation chamber for inflating an air bag;

an annular filter in said gas generation chamber adjacent an inner surface of said outer side wall for entrapping combustion residue from said gas generated in said housing before discharge of said gas through said exit ports;

a pair of resilient annular sealing rings for sealing between facing interior surfaces of said opposite end walls and respective, adjacent, annular opposite end portions of said annular filter for preventing gas generated in said housing from bypassing said filter to reach said gas exit ports;

said outer side wall having a crimp-formed end flange engaging at least one of said end walls to close said housing and compress said resilient sealing rings to seal said opposite end portion of said filter to seal against blow-by; and

at least said inner side wall having at least one end crimped over against one of said end walls for closing said housing means to form said sealed enclosure.

12. The housing of claim 11, including:

outer port sealing means secured adjacent an inside surface of said outer side wall for sealing between said exit ports and said gas generation chamber in said enclosure.

13. The housing of claim 11, wherein:

at least one of said end walls has a central opening therein; and

including

a closure wall integral with said inner side wall engaging said one end wall to close said opening.

14. The housing of claim 11, wherein:

at least one of said end walls has a central opening therein; and

said inner side wall extends through said opening and is crimped over against an outer surface of said one end wall around said opening to seal between said inner side wall and said one end wall.

15. The housing of claim 14, wherein:

both of said end walls have a central opening; and

said inner side wall extends through said openings and is crimped over against outside surfaces of said end walls around said openings to seal between said inner side wall and both said end walls.

16. The housing of claim 11, wherein:

said inner side wall and a central portion of an end wall form a cup for containing said ignition means.

17. The housing of claim 11, including radial flange means secured to said outer side wall for mounting said housing.

50. The housing of claim 17, wherein:

said radial flange means includes an inner ring portion welded to said outer side wall.

18. A housing for an air bag inflator, comprising:

a base and a spaced apart coaxial aligned top wall having matching aligned peripheral edges and aligned central openings;

a tubular outer side wall extending between said aligned peripheral edges of said base and said top wall and having a plurality of gas exit ports;

an annular filter in said housing adjacent an inner surface of said outer side wall for entrapping combustion residue from said gas generated in said housing before discharge of said gas from said housing;

a pair of resilient annular sealing rings for sealing between facing interior surfaces of said base and top walls and, respective, adjacent, annular opposite end portions of said annular filter for preventing gas generated in said housing from bypassing said filter to reach said outer side wall;

said tubular outer side wall having at least one crimp-formed annular end flange engaging an outer surface of said bottom wall for closing said housing and compressing said sealing rings against said opposite end portions of said filters to seal against blow-by;

a tubular inner side wall extending between said aligned central openings and crimped over against opposite outer faces of said base and said top wall; and

said inner side wall having a plurality of ignition ports therein and defining an ignition chamber for containing ignition materials ignitable to direct hot ignition gas outwardly through said ports for initiating combustion of gas generating materials contained in a combustion chamber defined outside of said ignition chamber between said inner and outer side walls, said outer side having a plurality of diffuser ports for directing generated gas outwardly to inflate an associated air bag.

19. The housing of claim 18, wherein:

said inner side wall extends through said openings and is crimped over for sealing against an outer surface of said base and top wall around an edge of said opening therein.

20. The housing of claim 19, wherein:

said top and bottom walls have central openings of equal size; and

said inner side wall extends through said openings and is crimped over against outside surfaces of said top and bottom walls around said openings for sealing between said inner side wall and both said end walls.

21. The housing of claim 18, wherein:

said inner side wall includes an integral wall adjacent an end portion forming a cup for containing said ignition means.

22. The housing of claim 21, wherein:

said ignition means is held in said cup by sealing means adjacent an opposite end portion of said inner side wall.

23. The inflator of claim 18, including:

a plurality of said crimp-formed annular end flanges formed adjacent opposite ends of said outer side wall for respectively sealingly engaging said base and said top wall.

24. The inflator of claim 18, wherein:

said inner side wall includes an integral closed end forming a central wall portion closing an opening in said top wall.

25. The housing of claim 18, wherein:

said inner side wall has an integral closure wall adjacent one end forming a central segment of said top wall.

26. The housing of claim 18, wherein:

said ignition materials are secured to an inside surface of said inner side wall and said closure; and

sealing means spaced apart from said one end of said inner side wall for sealing said ignition material in said ignition chamber.

27. The housing of claim 26, wherein:

said ignition materials are hermetically sealed in said ignition chamber.

28. A housing for an air bag inflator for containing ignition material, gas generating material and a filter, comprising:

a base having a central opening and an outer peripheral edge in coaxial alignment therewith, and a cover having a top wall spaced opposite said base and having a depending, peripheral outer side wall having a plurality of gas exit ports;

an annular filter in said housing adjacent an inner surface of said outer side wall for entrapping combustion residue from said gas generated in said housing before discharge of said gas from said housing;

a pair of resilient annular sealing rings for sealing between facing interior surfaces of said base and top walls and respective, adjacent, annular opposite end portions of said annular filter for preventing gas generated in said housing from bypassing said filter to reach said outer side wall;

said outer side wall having an annular end flange at a lower end portion crimped over against a lower surface of said base to close said housing and compress said sealing rings to seal said opposite annular end portions of said filter to seal against blow-by;

an inner side wall in coaxial alignment with said outer side wall having an upper end in contact with said top wall and a lower end portion crimped over against said lower surface of said base defining a central ignition chamber for said ignition material; and

said inner and outer side wall defining an annular outer chamber for containing said gas generating material and said filter.

29. The inflator of claim 28, wherein:

one end of said inner side wall is integrally formed with an adjacent end wall and an opposite end of said inner side wall is joined with a top wall and base in a crimp-formed joint.

30. The inflator of claim 28, wherein:

one end of said inner side wall is welded to an adjacent end wall and an opposite end of said inner side wall is joined with a top wall and base in a crimp-formed joint.

31. The housing of claim 28, wherein:

said filter has a cylindrical outer surface adjacent an inside surface of said outer side wall and a pair of said annular opposite end portions facing parallel of said base and said top wall;

said pair of annular resilient sealing rings being disposed on said annular opposite end faces against said base and top wall; and

said annular end flange at said, lower-end portion of said outer side wall biasing said base toward said top wall to compress said annular sealing rings against said opposite end portions of said filter for preventing blow-by of generated gas around said filter while moving from said generant material toward said exit ports in said outer side wall.

32. The housing of claim 28, including:

an adapter plug closing a lower end of said inner side wall; and

wherein said ignition material is mounted in said adapter plug.

33. The housing of claim 32, wherein:

said adapter plug includes flange means overlying said crimped-over lower end portion of said inner side wall.

34. The housing of claim 32, wherein:

said adapter plug includes an upper end portion adapted to be bent over to secure said ignition material in said plug.

35. The housing of claim 33, wherein:

said adapter plug includes an outer annular washer-like element sealed against an outside surface of said base.

36. The housing of claim 28, including:

ignition-enhancing means mounted in said ignition chamber adjacent said ignition material and said top wall.

37. The housing of claim 36, including:

spring washer means engaging said inner side wall for securing said ignition enhancer in said ignition chamber.

48. The housing of claim 33, wherein:

said flange means of said adapter plug is welded to said base outwardly of said central opening.

38. A housing for an air bag inflator, comprising:

a base having a central opening and an outer peripheral edge;

a cover including a top wall spaced opposite said base having a central opening aligned with said central opening in said base and including a depending outer side wall having a plurality of gas exit ports and having a lower end joined to said base adjacent said outer peripheral edge;

an annular filter in said housing adjacent an inner surface of said outer side wall for entrapping combustion residue from said gas generated in said housing before discharge of said gas through said exit ports;

a pair of resilient annular sealing rings for sealing between facing interior surfaces of said base and top walls and respective, adjacent annular, opposite end portions of said annular filter for preventing gas generated in said housing from bypassing said filter to reach said gas exit ports;

said outer side wall having an annular end flange at a lower end crimp-formed over against said base to close said housing while compressing said sealing rings to seal between said opposite end portions of said base and top wall to prevent filter blow-by; and

a ported inner side wall extending between said aligned central openings of said base and top wall having a lower end portion crimped over against an outer surface of said base around said central opening and having a flanged end wall at the upper end engaging an outer surface of said top wall forming a central ignition chamber and a combustion chamber outwardly thereof.

39. The housing of claim 38, wherein:

said inner side wall is formed by a forged member and said flanged end wall is an integral portion thereof.

40. The housing of claim 38, including:

ignition-enhancing means mounted in said combustion chamber adjacent said flanged end wall.

41. The housing of claim 40, wherein:

said ignition-enhancing means is secured in said ignition chamber by an upset portion formed on an inside surface of said inner side wall.

42. The housing of claim 38, including:

an adapter plug for closing a lower end of said ignition chamber; and

said inner side wall includes an inwardly directed end portion crimped-over against a surface on said adapter plug to secure the plug in place.

43. The housing of claim 42, including:

an ignition squib mounted in said adapter plug and adapted to be electrically activated to ignite for deployment of an associated air bag.

44. The housing of claim 43, including:

sealing means between said adapter plug and an inside surface of said inner side wall.

45. The housing of claim 42, wherein:

said ignition squib includes electrical terminals protruding out from said adapter plug for connection to a source generating an electrical ignition signal.

46. The housing of claim 38, wherein:

said outer side wall and said base are formed with abutting radially outwardly projecting peripheral flanges, and including;

a crimp-formed ring engaging said peripheral flanges securing the same together to seal said housing.

47. The housing of claim 46, including:

an externally applied seal ring between said peripheral flanges.

49. The housing of claim 46, including:

mounting flange means extending radially outwardly of said outer side wall for mounting said housing integrally joined with said crimp-formed ring.

51. The housing of claim 40, wherein:

said ignition enhancing means is secured to an inside surface of a lower end portion of said inner side wall by welding establishing a hermetic seal.