Airbag assembly

• US 5,346,248 A
• Filed: 06/02/1992
• Issued: 09/13/1994
• Est. Priority Date: 06/02/1992
• Status: Expired due to Term

• Current Assignee: TRW Vehicle Safety Systems Incorporated (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Vehicle Safety Systems Incorporated (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Farquhar, Dennis F., Redmond, Lynn M., Rhein, John F.
• Primary Examiner(s): Focarino, Margaret A.
• Assistant Examiner(s): DICKSON, PAUL N
• Application Number:
  US07/892,200
• Time in Patent Office: 833 Days
• Field of Search: 280/728 A, 280/741 R, 280/743 R, 280/731, 280/732, 280/736, 280/728 B
• US Class Current: 280/728.1
• CPC Class Codes: B60R 21/2171 specially adapted for elongated cylindrical or bottle-like inflators with a symmetry axis perpendicular to the main direction of bag deployment, e.g. extruded reaction canisters B60R21/2176 takes precedence
• CPC Class Codes: B60R 21/276 with means to vent the inflation fluid source, e.g. in case of overpressure B60R21/30 takes precedence; venting means on inflatable member walls B60R21/239

Abstract

An airbag assembly 20 includes an inflator 100, a coupling device 300, an airbag 400, a cover 500 and a reaction device 600. The inflator 100 is positioned to supply inflation fluid to the airbag 400. The coupling device 300, the airbag 400, and the cover 500 are coupled to the reaction device 600 with a minimum number of fastening elements 28. The airbag assembly 20 further comprises a heat shield 200 which cradles a rear portion of the inflator 100 and which is coupled to the reaction device 600. The heat shield 200 is coupled to the reaction device by the fastening elements 28.

Claims

1. An airbag assembly comprising an inflator/shield subassembly, a coupling device, an airbag, a cover and a reaction device;

said inflator/shield subassembly being positioned to supply inflation fluid to said airbag;

said coupling device, said airbag, said inflator/shield subassembly and said cover being coupled to said reaction device with a set of fastening elements each of which extends through portions of said airbag, said cover, said reaction device and said inflator/shield subassembly.

2. An airbag assembly as set forth in claim 1, wherein said inflator/shield subassembly further comprises a heat shield which cradles a portion of an inflator and which is coupled to said reaction device by said fastening elements.

3. An airbag assembly as set forth in either claim 1 or claim 2 wherein said fastening elements each comprise a shaft portion and a locking portion which mates with said shaft portion to lock said fastening element in a desired position and wherein said locking portions are situated exterior of said reaction device.

4. An air bag assembly as set forth in claim 3 wherein said shaft portions of said fastening elements are integrally joined to said coupling device.

5. An airbag assembly comprising an inflator/shield subassembly, a coupling device, an airbag, a cover, and a reaction device;

said inflator/shield subassembly being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating portion which receives a front portion of said inflator/shield subassembly;

said coupling device, said airbag, said inflator/shield subassembly and said cover being coupled to said reaction device with a set of fastening elements; and

each of said fastening elements extending through portions of said airbag, said cover, said inflator/shield subassembly and said rear wall of said reaction device.

6. An airbag assembly as set forth in claim 5 wherein:

said coupling device includes a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device includes a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements are joined to said coupling surface of said coupling device;

said fastening elements extend through said coupling surface of said reaction device; and

said coupling surface of said coupling device and said coupling surface of said reaction device are disposed in planes parallel to each other.

7. An airbag assembly as set forth in claim 6 wherein said inflator-accommodating portion of said coupling device defines a rectangular opening shaped and sized to receive said front portion of said inflator housing.

8. An airbag assembly as set forth in claim 6 wherein:

said airbag comprises a bag which is formed from a flexible fabric and which has a mouth portion defining a fluid inlet opening;

said mouth portion includes coupling openings sized and arranged to receive portions of said fastening elements;

said cover comprises a coupling flange including coupling openings which receive said portions of said fastening elements; and

said mouth portion and said cover coupling flange are sandwiched between said rear wall of said coupling device and said rear wall of said reaction device.

9. An airbag assembly as set forth in claim 8 wherein said airbag additionally includes a retaining member which is joined to said mouth portion, said retaining member being positioned between said fluid inlet opening and said coupling openings of said airbag.

10. An airbag assembly as set forth in claim 5 wherein said inflator-accommodating portion of said reaction device comprises a curved impression which conforms to the outer contour of said front portion of said inflator/shield subassembly.

11. An airbag assembly as set forth in claim 5 wherein said inflator-accommodating portion of said reaction device defines a rectangular opening sized and shaped to receive said front portion of said inflator/shield subassembly.

12. An airbag assembly as set forth in claim 5 further comprising mounting brackets attached to said reaction device and adapted to mount said reaction device to a vehicle instrument panel.

13. An airbag assembly as set forth in claim 5 wherein said reaction device consists essentially of a monolithic structure.

14. An airbag assembly as set forth in claim 5 wherein portions of said cover are sandwiched between said reaction device and said coupling device.

15. An airbag assembly comprising an inflator, a coupling device, an airbag, a cover, and a reaction device;

said inflator being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating portion which receives a front portion of said inflator;

said cover being formed in one piece;

said coupling device, said airbag, and said cover being coupled to said reaction device with a set of fastening elements;

each of said fastening elements extending through said airbag, said cover and said rear wall of said reaction device;

said coupling device including a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device including a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements being joined to said coupling surface of said coupling device;

said fastening elements extending through said coupling surface of said reaction device;

said coupling surface of said coupling device and said coupling surface of said reaction device being disposed in planes parallel to each other; and

said inflator-accommodating portion of said coupling device comprising a curved impression which conforms to the outer contour of a central section of said front portion of said inflator and which includes a series of openings aligned with said primary discharge orifices.

16. An airbag assembly comprising an inflator, a coupling device, an airbag, a cover, and a reaction device;

said inflator being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating portion which receives a front portion of said inflator;

said cover being formed in one piece;

said coupling device, said airbag, and said cover being coupled to said reaction device with a set of fastening elements;

each of said fastening elements extending through said airbag, said cover and said rear wall of said reaction device;

said coupling device including a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device including a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements being joined to said coupling surface of said coupling device;

said fastening elements extending through said coupling surface of said reaction device;

said coupling surface of said coupling device and said coupling surface of said reaction device being disposed in planes parallel to each other;

said airbag comprising a bag which is formed from a flexible fabric and which has a mouth portion defining a fluid inlet opening;

said mouth portion including coupling openings sized and arranged to receive portions of said fastening elements;

said cover comprising a coupling flange including coupling openings which receive said portions of said fastening elements;

said mouth portion and said cover coupling flange being sandwiched between said rear wall of said coupling device and said rear wall of said reaction device; and

said coupling device being enclosed with a hem formed in said mouth portion of said bag and said hem including said coupling openings of said airbag.

17. An airbag assembly comprising an inflator, a coupling device, an airbag, a cover, and a reaction device;

said inflator being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating portion which receives a front portion of said inflator;

said cover being formed in one piece;

said coupling device, said airbag, and said cover being coupled to said reaction device with a set of fastening elements; and

each of said fastening elements extending through said airbag, said cover and said rear wall of said reaction device

said coupling device including a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device including a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements being joined to said coupling surface of said coupling device;

said fastening elements extending through said coupling surface of said reaction device; and

said coupling surface of said coupling device and said coupling surface of said reaction device being disposed in planes parallel to each other;

said airbag comprising a bag which is formed from a flexible fabric and which has a mouth portion defining a fluid inlet opening;

said mouth portion including coupling openings sized and arranged to receive portions of said fastening elements;

said cover comprising a coupling flange including coupling openings which receive said portions of said fastening elements;

said mouth portion and said cover coupling flange being sandwiched between said rear wall of said coupling device and said rear wall of said reaction device;

said airbag assembly further comprising a heat shield which cradles a rear portion of said inflator;

said heat shield being integrally joined to said reaction device; and

said airbag assembly further comprising a deflecting device which deflects inflation fluid away from said airbag mouth portion and said cover coupling flange and which directs the inflation fluid toward said airbag fluid inlet during deployment of said airbag assembly.

18. An airbag assembly as set forth in claim 17 wherein said deflecting device is positioned between said coupling surface of said reaction device and said coupling surface of said coupling device.

19. An airbag assembly comprising an inflator, a coupling device, an airbag, a cover, and a reaction device;

said inflator being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating, portion which receives a front portion of said inflator;

said coupling device, said airbag, and said cover being coupled to said reaction device with a set of fastening elements;

each of said fastening elements extending through said airbag, said cover and said rear wall of said reaction device;

said coupling device including a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device including a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements being joined to said coupling surface of said coupling device;

said fastening elements extending through said coupling surface of said reaction device;

said coupling surface of said coupling device and said coupling surface of said reaction device are disposed in planes parallel to each other; and

said inflator-accommodating portion of said coupling device comprising a curved impression which conforms to the outer contour of a central section of said front portion of said inflator and which includes a series of openings aligned with said primary discharge orifices.

20. An airbag assembly comprising an inflator, a coupling device, an airbag, a cover, and a reaction device;

said inflator being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating portion which receives a front portion of said inflator;

said coupling device, said airbag, and said cover being coupled to said reaction device with a set of fastening elements;

each of said fastening elements extending through said airbag, said cover and said rear wall of said reaction device

said coupling device including a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device including a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements being joined to said coupling surface of said coupling device;

said fastening elements extending through said coupling surface of said reaction device;

said coupling surface of said coupling device and said coupling surface of said reaction device being disposed in planes parallel to each other;

said airbag comprising a bag which is formed from a flexible fabric and which has a mouth portion defining a fluid inlet opening;

said mouth portion including coupling openings sized and arranged to receive portions of said fastening elements;

said cover comprising a coupling flange including coupling openings which receive said portions of said fastening elements;

said mouth portion and said cover coupling flange being sandwiched between said rear wall of said coupling device and said rear wall of said reaction device;

said reaction device further comprising top and bottom walls and side walls;

said top and bottom walls of said reaction device extending perpendicularly to and frontward from top and bottom edges of said rear wall of said reaction device;

said side walls of said reaction device extending perpendicularly to and frontward from side edges of said rear wall and joining, at top and bottom edges, with said top and bottom walls of said reaction device;

said coupling device further comprising a top wall, a bottom wall, and side walls;

said top and bottom walls of said coupling device extending perpendicularly to and frontward from top and bottom edges of said rear wall of said coupling device;

said side walls of said coupling device extending perpendicularly to and frontward from side edges of said rear wall of said coupling device and joining, at top and bottom edges with said top and bottom walls of said coupling device;

said cover comprising a front wall, side walls, and top and bottom walls;

said top and bottom walls of said cover extending rearwardly from top and bottom edges of said front wall and said side walls of said cover extending rearwardly from side edges of said front wall;

said coupling device being positioned within a cavity formed by said walls of said reaction device; and

portions of said airbag and said cover being sandwiched between said top and bottom walls of said coupling device and said top and bottom walls of said reaction device.

21. An airbag assembly as set forth in claim 20 wherein said top and bottom edges of said side walls of said cover are joined with said top and bottom walls of said cover, and wherein front edges of said side walls of said cover are unjoined with said front wall of said cover.

22. An airbag assembly as set forth in claim 21 wherein:

said top and bottom walls of said cover each include a proximate portion, a distal portion, and a coupling flange portion;

said proximate portions taper inwardly from the top and bottom edges of said front wall;

said distal portions extend from said proximate portions and are generally parallel to each other;

said coupling flange of said cover extending perpendicularly inwardly from free ends of said distal portions;

said proximate portion of said bottom wall includes a designed weakness so that, during deployment of said airbag assembly, said front wall will pivot upwardly;

said distal portions are sandwiched between said top and bottom walls of said coupling device and said top and bottom walls of said reaction device; and

said coupling flange portions collectively form said coupling flange of said cover and each include some of said coupling openings of said cover.

23. An airbag assembly as set forth in claim 22 wherein said coupling openings of one of said coupling flange portions comprise closed circular openings through which said shaft portions are inserted and said coupling openings of the other of said coupling flange portions comprise unclosed openings about which said shaft portions are snapped.

24. An airbag assembly as set forth in claim 20 wherein:

said top and bottom walls of said coupling device include ribs;

said top and bottom walls of said reaction device include ribs shaped and arranged similarly to said ribs of said coupling device;

said top and bottom walls of said cover include depressions shaped and arranged similarly to said ribs of said coupling device and said reaction device;

said depressions of said cover are sandwiched between said ribs of said coupling device and said ribs of said reaction device; and

said ribs of said coupling device and said ribs of said reaction device cooperate to protect against fish-mouthing of said reaction device during deployment of said airbag assembly.

25. An airbag assembly as set forth in claim 24 wherein said ribs of said coupling device, said ribs of said reaction device, and said depressions of said cover are finger-shaped.

26. An air bag assembly as set forth in claim 20 wherein said coupling device consists essentially of a monolithic structure.

27. An airbag assembly as set forth in claim 20 wherein:

said airbag assembly further comprises a heat shield which cradles a rear portion of said inflator;

said heat shield includes a planar coupling surface which is disposed in a plane parallel to said coupling surfaces of said coupling device and said reaction device; and

said fastening elements extend through said coupling surface of said heat shield thereby coupling said heat shield to said reaction device.

28. An airbag assembly comprising an inflator, a heat shield, a coupling device, an airbag, a cover and a reaction device;

said inflator being coupled to said heat shield and positioned to supply inflation fluid to said airbag;

said heat shield, said coupling device, said airbag, and said cover being coupled to said reaction device with a set of fasteners;

each of said fasteners extending through said heat shield, said airbag, said cover, and said reaction device.

29. An airbag assembly as set forth in claim 28 wherein:

said inflator includes a cylindrical housing having a radial dimension and an axial dimension substantially greater than said radial dimension;

said inflator further includes coupling members which are attached to said housing;

said housing encloses a fluid source and includes a front portion and a rear portion;

said front portion of said housing includes primary discharge orifices which release inflation fluid to said airbag during deployment of said airbag assembly.

30. An airbag assembly as set forth in claim 29 wherein:

said cover includes alignment projections;

said reaction device includes alignment openings which receive said projections; and

said heat shield includes dimples which receive said alignment projections.

31. An airbag assembly as set forth in claim 30 wherein:

said reaction device comprises a rear wall having an inflator-accommodating portion which receives said front portion of said inflator housing and a planar coupling surface which surrounds said inflator-accommodating portion;

said planar coupling surface includes said alignment openings;

said cover comprises a front wall, a top wall and a bottom wall, said top and bottom walls extending inwardly from said front wall;

said top and bottom walls include coupling flanges which are sandwiched between said rear wall of said reaction device and said coupling device;

said alignment projections extend rearwardly from said coupling flanges of said cover; and

said heat shield includes a main wall which cradles said rear portion of said inflator housing and which includes said dimples.

32. An airbag assembly as set forth in claim 29 wherein:

said heat shield includes a main wall, a side wall, and a coupling flange;

said main wall cradles said rear portion of said inflator housing; and

said side wall cooperates with said coupling members of said inflator to couple said inflator and said heat shield together.

33. An airbag assembly as set forth in claim 32 wherein:

said rear portion of said inflator housing defines secondary discharge orifices which vent inflation fluid from said housing during deployment of said airbag assembly; and

said main wall additionally includes a row of openings which are located on a rear region of said wall and which align with said secondary discharge orifices of said inflator.

34. An airbag assembly as set forth in claim 32 wherein said heat shield further includes a coupling flange which includes a coupling surface for said heat shield and which includes coupling openings to receive said primary fastening elements.

35. An airbag assembly as set forth in claim 34 wherein said heat shield consists essentially of a monolithic structure.

36. An airbag assembly as set forth in claim 34 wherein front edges of said main wall integrally join with said coupling surface of said reaction device.

37. An airbag assembly as set forth in claim 34 wherein:

said main wall is generally parabolic in cross-sectional shape and is sized to generously surround said rear portion of said inflator housing;

said main wall includes indentations which cause a deviation from said parabolic shape and which clasp regions of said rear portion of said inflator housing, said regions being located away from said secondary discharge orifices;

said side wall closes one side end of said main wall and thus is parabolic in shape;

said coupling flange extends from front edges of said main wall and a front edge of said side wall to form a three-sided frame;

said coupling flange includes coupling portions which extend substantially perpendicularly from said indentations;

said coupling portions are positioned in substantially the same plane and collectively form said coupling surface of said heat shield; and

each coupling portion includes an opening which receives a primary fastening element.

38. A method of assembling an airbag assembly comprising the steps of:

providing an inflator, a heat shield, a coupling device, an airbag, a cover, and a reaction device;

coupling the inflator to the heat shield to form an inflator/shield subassembly;

coupling the coupling device, the airbag, and the cover together to form an airbag/cover subassembly;

coupling the airbag/cover subassembly to the reaction device to form a reaction/airbag/cover subassembly; and

coupling the inflator/shield subassembly to the reaction/airbag/cover subassembly to complete the airbag assembly.

39. A method as set forth in claim 38 further comprising the step of providing a set of primary fastening elements and wherein said coupling steps include the steps of using the primary fastening elements to:

couple the coupling device, the airbag, and the cover together to form the airbag/cover subassembly;

couple the reaction device to the airbag/cover subassembly to form the reaction/airbag/cover subassembly; and

couple the inflator/shield subassembly to the reaction/airbag/cover subassembly to complete the airbag assembly.

40. A method as set forth in claim 39 wherein:

said step of providing a set of primary fastening elements comprises the step of providing fastening elements which each include a shaft portion and a locking portion which mates with the shaft portion to lock said fastening element in a desired position; and

said coupling steps include the step of mating a locking portion to a section of a shaft portion exterior to the airbag assembly whereby the locking portions are visible from the exterior of said airbag assembly.

41. A method of assembling an airbag assembly comprising the steps of:

providing an inflator, a heat shield, a coupling device, an airbag, a cover, and a reaction device;

coupling the inflator to the heat shield to form an inflator/shield subassembly;

coupling the coupling device, the airbag, and the cover together to form an airbag/cover subassembly;

coupling the airbag/cover subassembly to the reaction device to form a reaction/airbag/cover subassembly; and

coupling the inflator/shield subassembly to the reaction/airbag/cover subassembly to complete the airbag assembly;

wherein said step of coupling the inflator/shield subassembly to the reaction/airbag/cover subassembly is performed at a different location than said step of forming the airbag/cover subassembly.

48. An airbag assembly as set forth in claim 41 wherein:

said coupling device includes a rear wall having an inflator-accommodating portion, which receives said front portion of said inflator/shield subassembly, and a planar coupling surface, which surrounds said inflator-accommodating portion;

said rear wall of said reaction device includes a planar coupling surface which surrounds its inflator-accommodating portion;

said fastening elements are joined to said coupling surface of said coupling device;

said fastening elements extend through said coupling surface of said reaction device; and

said coupling surface of said coupling device and said coupling surface of said reaction device are disposed in planes parallel to each other.

42. A method of assembling an airbag assembly comprising the steps of:

providing an inflator, a heat shield, a coupling device, an airbag, a cover, and a reaction device;

coupling the inflator to the heat shield to form an inflator/shield subassembly;

coupling the coupling device, the airbag, and the cover together to form an airbag/cover subassembly;

coupling the airbag/cover subassembly to the reaction device to form a reaction/airbag/cover subassembly; and

coupling the inflator/shield subassembly to the reaction/airbag/cover subassembly to complete the airbag assembly;

wherein said step of coupling the coupling device, the airbag, and the cover together comprises positioning the airbag mouth portion around the coupling device.

43. A method of assembling an airbag assembly comprising the steps of:

providing an inflator, a heat shield, a coupling device, an airbag, a cover, and a reaction device;

coupling the inflator to the heat shield to form an inflator/shield subassembly;

coupling the coupling device, the airbag, and the cover together to form an airbag/cover subassembly;

coupling the airbag/cover subassembly to the reaction device to form a reaction/airbag/cover subassembly; and

coupling the inflator/shield subassembly to the reaction/airbag/cover subassembly to complete the airbag assembly;

wherein said step of coupling the coupling device, the airbag, and the cover together comprises enclosing said coupling device with a hem formed in the mouth portion of the bag.

44. A method of assembling an airbag assembly comprising the steps of:

providing an inflator, a heat shield, a coupling device, an airbag, a cover, and a reaction device;

coupling the heat shield and the reaction device together to form a combined heat shield/reaction device;

coupling the inflator to the combined heat shield/reaction device to form a reaction/inflator/shield subassembly;

coupling the coupling device, the airbag, and the cover together to form an airbag/cover subassembly; and

coupling the reaction/inflator/shield subassembly and the airbag/cover subassembly together to complete the airbag assembly.

45. A method as set forth in claim 44 further comprising the step of providing a set of primary fastening elements and wherein said coupling steps include the steps of using the primary fastening elements to:

couple the coupling device, the airbag, and the cover together to form the airbag/cover subassembly; and

couple the airbag/cover subassembly, and the reaction/inflator/shield subassembly together to complete the airbag assembly.

46. A method as set forth in claim 45 wherein said step of forming the combined heat shield/reaction device comprises the step of integrally forming the heat shield and the reaction device together.

47. An airbag assembly comprising an inflator/shield subassembly, a coupling device, an airbag, a cover, and a reaction device;

said inflator/shield subassembly being positioned to supply inflation fluid to said airbag;

said reaction device including a rear wall having an inflator-accommodating portion which receives a front portion of an inflator housing;

said coupling device, said airbag, said inflator/shield subassembly and said cover being coupled to said reaction device with a set of fastening elements;

each of said fastening elements extending through said airbag, said cover, said inflator/shield subassembly and said rear wall of said reaction device;

said inflator-accommodating portion of said reaction device comprising a curved impression which conforms to the outer contour of said front portion of said inflator housing.

49. An airbag assembly as set forth in claim 47 wherein:

said airbag comprises a bag which is formed from a flexible fabric and which has a mouth portion defining a fluid inlet opening;

said mouth portion includes coupling openings sized and arranged to receive portions of said fastening elements;

said cover comprises a coupling flange including coupling openings which receive said portions of said fastening elements; and

said mouth portion and said cover coupling flange are sandwiched between said rear wall of said coupling device and said rear wall of said reaction device.

50. An airbag assembly as set forth in claim 47 wherein portions of said cover are sandwiched between said reaction device and said coupling device.