Inflator assembly

• US 5,584,504 A
• Filed: 12/19/1995
• Issued: 12/17/1996
• Est. Priority Date: 03/24/1995
• Status: Expired due to Fees

• Current Assignee: TRW Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: O'Loughlin, John P., Fischer, Craig M., Cuevas, Jess A., Skouson, John D.
• Primary Examiner(s): Culbreth, Eric D.
• Application Number:
  US08/574,548
• Time in Patent Office: 364 Days
• Field of Search: 280/737, 280/740, 280/741, 280/736, 280/742, 222/3, 222/5, 102/530, 102/531
• US Class Current: 280/737
• CPC Class Codes: B60R 21/26 characterised by the inflation fluid source or means to control inflation fluid flow arrangement or mounting thereof to the vehicle B60R21/20; blasting cartridges for producing gas under pressure in general F42B3/04; initiators or igniters therefor F42B3/10
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators
• CPC Class Codes: B60R 21/274 characterised by means to rupture or open the fluid source
• CPC Class Codes: F42B 3/04 for producing gas under pressure generators of inflation fluid especially adapted for vehicle air bags B60R21/26

Abstract

An apparatus (10) for inflating an air bag includes a container (12) for holding a stored supply of gas under pressure. A body (20) of gas generating material is disposed in a housing (22). A cup shaped closure member (24) blocks a flow of gas through an annular array of passages (28) formed in an end wall (58) of the container (12). The cup shaped closure member (24) has a frangible section (176). Upon ignition of the body (20) of gas generating material, the gas applies pressure against an end wall (166) of the closure member (24) to break the frangible section (176) of the closure member. The pressure applied by the gas against the end wall (166) of the cup shaped closure member (24) moves the closure member toward an opposite end of the container (12). Gas flows from the container (12) through the openings (28) in the end wall of the container into a diffuser (36). The diffuser (36), closure member (24) and housing (22) which holds the body (20) of gas generating material are all connected to the end wall (58) of the container (12).

Claims

1. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a supply of gas;

surface means for defining a gas discharge opening for directing gas from said container;

a quantity of pressure producing material, said quantity of pressure producing material being ignitable to produce pressure;

said container having a closure member blocking said gas discharge opening and at least partially enclosing said quantity of pressure producing material, said closure member including a breakable portion adjacent to said discharge opening, a side wall portion extending from said breakable portion and at least partially enclosing said quantity of pressure producing material, and an end wall portion connected with said side wall portion of said closure member; and

igniter means for igniting said quantity of pressure producing material to create pressure against said end wall portion of said closure member to break said breakable end portion of said closure member and to move at least said side wall portion and said end wall portion of said closure member away from said discharge opening to enable gas to flow through said discharge opening toward the vehicle occupant restraint.

2. An apparatus as set forth in claim 1 wherein said breakable portion of said closure member includes an area of reduced thickness which is broken upon application of pressure against said end wall portion of said closure member.

4. An apparatus as set forth in claim 1 wherein said quantity of pressure producing material comprises a body of ignitable material and further including seal means disposed between said igniter means and said body of ignitable material for blocking the conduction of moisture from the environment to said body of ignitable material.

5. An apparatus as set forth in claim 1 wherein said quantity of pressure producing material comprises a body of ignitable material and further including a housing at least partially disposed within said closure member, said body of ignitable material being disposed in said housing.

6. An apparatus as set forth in claim 5 wherein said side wall portion of said closure member includes surface means for slidably engaging said housing during at least a portion of the movement of said side wall portion and end wall portion of said closure member away from said discharge openings.

7. An apparatus as set forth in claim 5 wherein said housing has a cylindrical outer side surface, said side wall portion of said closure member having a cylindrical inner side surface which is disposed in engagement with said cylindrical outer side surface of said housing.

8. An apparatus as set forth in claim 5 wherein said housing includes a base portion, a side wall portion extending from said base portion and adjacent said side wall portion of said closure member, and an inner end portion opposite from said base portion, said breakable portion of said closure member extending around and being spaced from said base portion of said housing, said side wall portion of said closure member extending around and being disposed in engagement with said side wall portion of said housing, said end wall portion of said closure member extending across said inner end portion of said housing, said inner end portion of said housing including an opening through which combustion products flow from said body of ignitable material toward said end wall portion of said closure member upon ignition of said body of ignitable material.

9. An apparatus as set forth in claim 1 wherein said end wall portion of said closure member includes a plurality of projections which increase the rigidity of said end wall portion of said closure member.

10. An apparatus as set forth in claim 1 further including a housing associated with said container and said closure member and having a main portion and an outer end portion, said quantity of pressure producing material being disposed in said main portion of said housing;

diffuser means for directing a flow of gas from said discharge openings, said diffuser means including an end wall which extends axially outward of the outer end portion of said housing to shield the outer end portion of said housing against unintended engagement with objects, said diffuser means defining a diffuser chamber which extends around said outer end portion of said housing and receives gas from said discharge openings, and said diffuser means including a plurality of passages through which gas flows from said diffuser chamber toward said vehicle occupant restraint.

11. An apparatus as set forth in claim 10 wherein said end wall of said diffuser means is connected to said outer end portion of said housing.

12. An apparatus as set forth in claim 1 wherein said side wall portion of said closure member has a portion of reduced thickness adjacent to said breakable portion of said closure member, said portion of reduced thickness being inwardly deflectable toward a central axis of said closure member under the influence of an increase in the pressure of the gas in said container.

13. An apparatus as set forth in claim 1 wherein said quantity of pressure producing material comprises a body of ignitable material and further including a housing, said body of ignitable material being disposed within said housing, said housing including a side wall and an end wall connected with said side wall, said end wall having a plurality of projections which engage said body of ignitable material to locate said body of ignitable material and said end wall relative to each other.

3. An apparatus as set forth in claim wherein said container includes a longitudinally extending side wall, an end wall connected with said side wall, said surface means for defining a discharge opening defining an annular array of discharge openings in said end wall, said breakable portion of said closure member being connected with said end wall.

14. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a stored supply of gas, said container including a longitudinally extending side wall, and an end wall connected with one end of said side wall;

a housing having a base section and a main section which extend from said end wall;

a quantity of pressure producing material disposed in said main section of said housing, said quantity of pressure producing material being ignitable to produce pressure;

said end wall having surface means for defining discharge openings for directing gas from said container;

a closure member which extends between said main section of said housing and said end wall to block a flow of gas from said container through said discharge openings, said closure member being connected with said end wall at a location which is spaced from said base section, said closure member having a frangible section which extends around said base section and is breakable to enable gas to flow from said container through said discharge openings; and

igniter means for igniting said quantity of pressure producing material to create pressure and effect a breaking of said frangible section of said closure member to enable gas to flow from said container through said discharge openings.

15. An apparatus as set forth in claim 14 wherein said closure member, said base section of said housing and said end wall of said container at least partially define a manifold space which extends around said base section and is connected in fluid communication with said discharge openings, said closure member being effective to block flow of the stored gas into the manifold space prior to breaking of the frangible section of said closure member, said closure member being ineffective to block flow of the stored gas into the manifold space after breaking of the frangible section of said closure member.

16. An apparatus as set forth in claim 15 wherein said closure member includes a portion of reduced thickness which is deflectable into the manifold space by gas pressure after breaking of the frangible section of said closure member.

17. An apparatus as set forth in claim 15 wherein said discharge openings are formed in said end wall of said container and are disposed in a circular array adjacent to said base section of said housing, said closure member being connected with said end wall of said container at a location which is disposed radially outward of said circular array of discharge openings.

18. An apparatus as set forth in claim 14 wherein said quantity of pressure producing material comprises a body of ignitable material, said closure member has an end wall portion which extends across an end of said main section of said housing, and said body of ignitable material being ignitable by said igniter means to provide combustion products which apply pressure against said end wall portion of said closure member to break said frangible section of said closure member.

19. An apparatus as set forth in claim 14 wherein said closure member includes a side wall portion which at least partially encloses and extends along said main section of said housing, an end wall portion connected with one end of said side wall portion and extending across an end of said main section of said housing opposite from said base section of said housing, and a skirt portion connected with a second end of said side wall portion and extending from said side wall portion along said base section of said housing to said end wall of said container, said skirt portion of said closure member having an end portion which is connected with said end wall of said container, said frangible section of said closure member being disposed in said skirt portion of said closure member.

20. An apparatus as set forth in claim 19 wherein said end wall portion, side wall portion, and skirt portion of said closure member are formed as one piece.

21. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a supply of gas under pressure, said container including a longitudinally extending side wall and an end wall connected with one end of said side wall, said end wall including surface means for defining an array of passages which extend through said end wall;

a housing connected with and extending through said end wall of said container at a generally central location within the array of passages;

a body of ignitable material disposed in said housing, said body of ignitable material being ignitable to produce combustion products;

igniter means disposed in said housing for igniting said body of ignitable material; and

diffuser means for directing a flow of gas from the passages in said first end wall, said diffuser means including an end wall connected to said housing, said diffuser means including a side wall connected to said end wall of said container outwardly of the array of passages, said side wall and end wall of said diffuser means cooperating with said end wall of said container and said housing to form a diffuser chamber which extends around a portion of said housing and receives gas from open ends of passages in said array of passages, said end wall of said diffuser means extending from said housing outwardly across the open ends of the passages to deflect gas flow from the passages toward said side wall of said diffuser means, said side wall of said diffuser means including a plurality of passages through which gas flows from said diffuser chamber.

22. An apparatus as set forth in claim 21 wherein said plurality of passages in said side wall of said diffuser means have an area which is larger than the area of the passages in said end wall of said container.

23. An apparatus as set forth in claim 21 wherein said end wall of said diffuser means extends transverse to axes of the passages through said end wall of said container, said side wall of said diffuser means having a cylindrical inner side surface with a central axis which is parallel to the central axis of the passages in said end wall of said container.

24. An apparatus as set forth in claim 21 wherein said housing has a tubular base portion which extends through said end wall of said container and a tubular main portion spaced from said end wall of said container, said tubular main portion of said housing having a first cross-sectional area in a plane perpendicular to a longitudinal axis of said housing, said tubular base portion of said housing having a second cross-sectional area in a plane perpendicular to the longitudinal axis of said housing, said first cross-sectional area being larger than said second cross-sectional area.

25. An apparatus as set forth in claim 21 wherein said housing includes a side wall which extends along a side portion of said body of ignitable material and an end wall which is connected with said side wall of said housing, said end wall of said housing having a plurality of passages through which gas from said body of ignitable material is conducted upon ignition of said body of ignitable material, said end wall of said housing having a plurality of projections which extend between the side portion of said body of ignitable material and said side wall of said housing and which engage the side portion of said body of ignitable material to locate said body of ignitable material and said end wall of said housing relative to each other.

26. An apparatus as set forth in claim 21 further including seal means disposed in said housing between said igniter means and said body of ignitable material for blocking the conduction of moisture from the environment around said apparatus to said body of ignitable material.

27. An apparatus as set forth in claim 21 further including seal means disposed in engagement with an outer side surface of said end wall of said container for blocking the conduction of moisture from the environment around said apparatus through the passages in said array of passages.

28. An apparatus as set forth in claim 21 further including closure means connected with said container for blocking a flow of gas through the passages in said end wall of said container, said closure means being breakable to enable gas to flow through the passages in said end wall of said container.

29. An apparatus as set forth in claim 28 wherein said closure means is connected to said end wall of said container at a location outwardly of the passages in said end wall of said container, said closure means, said housing and said end wall of said container at least partially defining a manifold space which extends around said housing and which is in fluid communication with the passages in said end wall of said container, said closure member being effective to block flow of the stored gas into the manifold space prior to breaking of said closure means, said closure means being ineffective to block flow of the stored gas into the manifold space after breaking of said closure means.

30. An apparatus as set forth in claim 29 wherein said end wall of said diffuser means has a central portion which is connected to an axial outer end portion of said housing and includes a rim portion which extends axially outward of the axial outer end portion of said housing to shield said housing against unintended force being applied thereto.

31. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a supply of gas under pressure, said container including a longitudinally extending side wall and an end wall connected with one end of said side wall, and surface means for defining a plurality of passages which extend through said end wall, said side wall of said container being fixedly secured to said end wall;

a housing connected to a central portion of said end wall;

a body of ignitable material disposed in said housing, said body of ignitable material being ignitable to produce combustion products;

closure means connected to said end wall for blocking a flow of gas through said passages, said closure means being breakable to enable gas to flow through said passages upon ignition of said body of ignitable material, said closure means having a circular end portion which is connected with said end wall of said container and a central portion which at least partially encloses a portion of said housing;

igniter means disposed in said housing for igniting said body of ignitable material; and

diffuser means connected to said end wall for diffusing a flow of gas from the passages, said diffuser means having passages for directing a flow of gas from said diffuser means in a direction transverse to the direction of flow of gas through said plurality of passages.

32. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a supply of gas under pressure, said container including a longitudinally extending side wall and an end wall connected with one end of said side wall, and surface means for defining a plurality of passages which extend through said end wall, said side wall of said container being fixedly secured to said end wall;

a housing connected to a central portion of said end wall;

a body of ignitable material disposed in said housing, said body of ignitable material being ignitable to produce combustion products;

closure means connected to said end wall for blocking a flow of gas through said passages, said closure means being breakable to enable gas to flow through said passages upon ignition of said body of ignitable material, said closure means including a breakable end portion connected with said end wall of said container at a location outwardly of said passages through said end wall of said container, a side wall portion extending from said breakable end portion and at least partially enclosing said housing, and an end wall portion connected with said side wall portion and extending across an end of said housing;

igniter means disposed in said housing for igniting said body of ignitable material; and

diffuser means connected to said end wall for diffusing a flow of gas from the passages, said diffuser means having passages for directing a flow of gas from said diffuser means in a direction transverse to the direction of flow of gas through said plurality of passages.

33. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a stored supply of gas;

a body of ignitable material, said body of ignitable material including an end surface and a side surface extending from said end surface;

a housing enclosing said body of ignitable material, said housing including a side wall which extends along the side surface of said body of ignitable material and an end wall which is connected with said side wall, said end wall having a plurality of passages through which combustion products from said body of ignitable material is conducted upon ignition of said body of ignitable material, said end wall having a plurality of projections which extend between the side surface of said body of ignitable material and said side wall of said housing and which engage the side surface of said body of ignitable material to locate said body of ignitable material and said end wall relative to each other, at least some of said passages in said end wall of said housing extending through said projections to enable combustion products to flow from said body of ignitable material; and

igniter means for igniting said body of ignitable material to produce combustion products which flow through the passages in said end wall of said housing to heat the stored supply of gas in said container.

34. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a stored supply of gas;

a body of ignitable material, said body of ignitable material including an end surface and a side surface extending from said end surface;

a housing enclosing said body of ignitable material, said housing including a side wall which extends along the side surface of said body of ignitable material and an end wall which is connected with said side wall, said end wall having a plurality of passages through which combustion products from said body of ignitable material is conducted upon ignition of said body of ignitable material, said end wall having a plurality of projections which extend between the side surface of said body of ignitable material and said side wall of said housing and which engage the side surface of said body of ignitable material to locate said body of ignitable material and said end wall relative to each other, said side surface defining multiple lobes of said body of ignitable material, said projections being disposed between adjacent lobes of said body of ignitable material; and

igniter means for igniting said body of ignitable material to produce combustion products which flow through the passages in said end wall of said housing to heat the stored supply of combustion products in said container.

35. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a stored supply of gas;

a body of ignitable material, said body of ignitable material including an end surface and a side surface extending from said end surface;

a housing enclosing said body of ignitable material, said housing including a side wall which extends along the side surface of said body of ignitable material and an end wall which is connected with said side wall, said end wall having a plurality of passages through which combustion products from said body of ignitable material is conducted upon ignition of said body of ignitable material, said end wall having a plurality of projections which extend between the side surface of said body of ignitable material and said side wall of said housing and which engage the side surface of said body of ignitable material to locate said body of ignitable material and said end wall relative to each other;

igniter means for igniting said body of ignitable material to produce combustion products which flow through the passages in said end wall of said housing to heat the stored supply of combustion products in said container; and

a body of auto-ignition material disposed in said housing adjacent to an end portion of said body of ignitable material opposite from said end wall of said housing, said body of auto-ignition material being ignitable at a lower temperature than said body of ignitable material.

36. An apparatus for use in inflating a vehicle occupant restraint, said apparatus comprising:

a container for holding a stored supply of gas;

a body of ignitable material, said body of ignitable material including an end surface and a side surface extending from said end surface;

a housing enclosing said body of ignitable material, said housing including a side wall which extends along the side surface of said body of ignitable material and an end wall which is connected with said side wall, said end wall having a plurality of passages through which combustion products from said body of ignitable material is conducted upon ignition of said body of ignitable material, said end wall having a plurality of projections which extend between the side surface of said body of ignitable material and said side wall of said housing and which engage the side surface of said body of ignitable material to locate said body of ignitable material and said end wall relative to each other;

igniter means for igniting said body of ignitable material to produce combustion products which flow through the passages in said end wall of said housing to heat the stored supply of combustion products in said container;

surface means for defining discharge openings for directing combustion products from said container; and

a closure member at least partially enclosing said housing, said closure member blocking a flow of gas from said container through said discharge openings, said closure member including a breakable portion, a side wall portion extending from said breakable portion along said side wall of said housing, and an end wall portion connected with said side wall portion of said closure member and extending across said end wall of said housing, said body of ignitable material being ignitable by said igniter means to produce combustion products which are conducted through the passages in said end wall of said housing and which apply pressure against said end wall of said closure member to break said breakable portion of said closure member and to move at least said side wall portion and said end wall portion of said closure member away from said housing thereby to enable combustion products from said body of ignitable material and the stored supply of combustion products to flow through said discharge openings toward the inflatable occupant restraint.