Inflator assembly

• US 5,131,680 A
• Filed: 03/19/1991
• Issued: 07/21/1992
• Est. Priority Date: 03/19/1991
• 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: McLeod, William, Coultas, Terry, Wipasuramonton, Paul, Hocking, James R.
• Primary Examiner(s): Rice, Kenneth R.
• Application Number:
  US07/671,947
• Time in Patent Office: 490 Days
• Field of Search: 280/736, 280/737, 280/741, 222/3
• US Class Current: 280/737
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators

Abstract

An inflator assembly inflates a vehicle occupant restraint. The inflator assembly includes a container which stores gas under pressure. A body of an ignitable pyrotechnic material is disposed within the container. An igniter assembly is actuatable in response to being struck to ignite the body of pyrotechnic material. An actuator assembly is provided to release the stored gas from the container and to actuate the igniter assembly. The actuator assembly includes a pyrotechnic which moves an actuator member to rupture a portion of the container and to strike the igniter assembly. Upon actuation of the igniter assembly, the pyrotechnic material is ignited and begins to burn. During initial burning of the pyrotechnic material, an orifice plate restricts a flow of combustion products to promote burning of the pyrotechic material. During continued burning of the pyrotechnic material, the flow of combustion products enlarges the size of the orifice in the orifice plate to reduce the restriction to the flow of combustion products. The combustion products heat the gas in the container to increase the fluid pressure in the container.

Claims

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

container means for storing gas under pressure;

a body of ignitable material within said container means;

igniter means for igniting said body of ignitable material; and

actuator means for releasing the stored gas from said container means and for actuating said igniter means to ignite said body of ignitable material, said actuator means including,

an actuator member movable along a path to establish a flow of stored gas from said container means and to actuate said igniter means to ignite said body of ignitable material, and

means for moving said actuator member along said path.

2. An apparatus as set forth in claim 1 wherein said actuator member ruptures a portion of said container means to release the stored gas from said container means as said actuator member moves along said path.

3. An apparatus as set forth in claim 1 wherein said igniter means is operable in response to being struck to ignite said body of ignitable material, said actuator member striking said igniter means as said actuator member moves along said path thereby to effect actuation of said igniter means to ignite said body of ignitable material.

4. An apparatus as set forth in claim 3 wherein said actuator member ruptures a portion of said container means to release the stored gas prior to striking said igniter means.

5. An apparatus as set forth in claim 1 wherein said body of ignitable material includes means for generating heat to heat the gas in said container means upon ignition of said body of ignitable material.

6. An apparatus as set forth in claim 1 wherein said means for moving said actuator member along said path includes a pyrotechnic charge and means for igniting said pyrotechnic charge.

7. An apparatus as set forth in claim 1 wherein said actuator means includes a cylinder, said actuator member being at least partially disposed in said cylinder and cooperating with said cylinder to form a chamber, said means for moving said actuator member including a pyrotechnic charge disposed in the chamber, said pyrotechnic charge being ignitable to generate a pressure in the chamber to propel said actuator member along said path toward said igniter means.

8. An apparatus as set forth in claim 1 wherein said igniter means includes ignition material which is ignitable to initiate burning of said body of ignitable material, a plurality of primer elements which are actuatable in response to being struck to ignite said ignition material, and an impact member disposed adjacent to said plurality of primer elements, said impact member being movable relative to said plurality of primer elements by said actuator member to effect actuation of said plurality of primer elements.

9. An apparatus as set forth in claim 1 wherein said container means includes means for defining an opening through which gas flows from said container means, said actuator member being movable through the opening into engagement with said igniter means to actuate said igniter means.

10. An apparatus as set forth in claim 1 further including housing means connected with said container means and enclosing said body of ignitable material, said housing means including means for defining an opening through which flame is directed into the stored gas in said container means during burning of the ignitable material.

11. An apparatus as set forth in claim 1 wherein said container means stores gas at a first pressure prior to operation of said actuator means to establish a flow of the stored gas from said container means, said actuator means being operable to enable a portion of the stored gas to flow from said container means prior to ignitable of said body of ignitable material with a resulting reduction in the pressure in said container means from the first pressure to a second pressure which is less than the first pressure, said body of ignitable material being effective to heat the gas in said container means to increase the pressure in said container means to a third pressure which is greater than the first pressure during burning of said body of ignitable material after ignition of said body at ignitable material by said igniter means.

12. An apparatus as set forth in claim 1 further including housing means for enclosing said body of ignitable material, said housing means including an end portion having surface means for defining a first orifice having a first area, an orifice plate disposed in said housing means adjacent to said end portion of said housing means and having a second orifice with a second area which is smaller than the first area, said first and second orifices conducting a flow of combustion products from said housing means during burning of said body of ignitable material, said orifice plate being deformable by the flow of combustion products to increase the size of said second orifice from the first area to an area which is at least approximately as great as the second area.

13. An apparatus for inflating a vehicle occupant restraint, said apparatus comprising:

container means for storing gas under pressure;

means for heating the stored gas, said means for heating the stored gas including a body of ignitable material which burns to produce heat;

igniter means actuatable in response to being struck to ignite said body of ignitable material;

actuator means for actuating said igniter means to ignite said body of ignitable material, said actuator means including,

an actuator member which is movable to strike said igniter means and thereby actuate said igniter means to ignite said body of ignitable material and

means for moving said actuator member.

14. An apparatus as set forth in claim 13 wherein said igniter means includes a plurality of primer elements which are actuatable in response to the application of force against said primer elements to effect ignition of said body of ignitable material, an impact member which is movable to apply force against said plurality of primer elements, said impact member being movable by said actuator member to apply force against said plurality of primer elements to effect actuation of said plurality of primer elements.

15. An apparatus as set forth in claim 14 wherein said impact member includes a plate with an annular projection from at least one side of said plate, said annular projection being disposed in abutting engagement with said plurality of primer elements.

16. An apparatus as set forth in claim 13 wherein said body of ignitable material and said igniter means are disposed within said container means, said actuator member being movable into said container means from a location outside of said container means to strike said igniter means.

17. An apparatus as set froth in claim 16 wherein said container means includes a burst disk which is rupturable upon movement of said actuator member into said container means to release the stored gas in said container means.

18. An apparatus as set forth in claim 13 further including housing means enclosing said body of ignitable material, said housing means including surface means for directing a flame into the stored gas in said container means to heat the stored gas during burning of said body of ignitable material.

19. An apparatus as set forth in claim 13 further including housing means for enclosing said body of ignitable material, said housing means including an end portion having surface means for defining a first orifice having a first area, an orifice plate disposed in said housing means adjacent to said end portion of said housing means and having a second orifice with a second area which is smaller than the first area, said first and second orifices conducting a flow of combustion products from said housing means during burning of said body of ignitable material, said orifice plate being deformable by the flow of combustion products to increase the size of said second orifice from the second area to an area which is at least approximately as great as the first area.

20. An apparatus for inflating a vehicle occupant restraint, said apparatus comprising:

container means for storing gas under pressure;

a body of ignitable material connected with said container means;

igniter means actuatable in response to being struck to ignite said body of ignitable material; and

actuator means for releasing the stored gas from said container means and for actuating said igniter means to ignite said body of ignitable material, said actuator means including an actuator member, and pyrotechnic means for moving said actuator member to rupture a portion of said container means and to strike said igniter means.

21. An apparatus as set forth in claim 20 wherein said igniter means and said body of ignitable material are disposed in said container means, at least a portion of said actuator member being movable from a location outside of said container means into said container means to rupture a portion of said container means and to strike said igniter means.

22. An apparatus as set forth in claim 20 wherein said container means includes wall means which at least partially defines an orifice and a burst disk which extends across the orifice to block a flow of gas from said container means, at least a portion of said actuator member being movable through said orifice to rupture said burst disk and release the stored gas from said container means.

23. An apparatus as set forth in claim 22 wherein said igniter means is disposed in alignment with the orifice and a leading end portion of said actuator member strikes said igniter mean after movement of the leading end portion of said actuator member through said burst disk.

24. An apparatus as set forth in claim 20 wherein said container means includes a wall which at least partially defines a chamber for holding the stored gas, a hollow manifold which extends through and is connected with said wall, said manifold having an inner portion which is at least partially disposed in the chamber and an opening connecting an interior portion of said manifold in fluid communication with the chamber, said manifold having an outer portion which is at least partially disposed outside of the chamber and having an opening connecting the interior portion of said manifold in fluid communication with the outside of said manifold, and a burst disk disposed in the interior portion of said manifold between the inner and outer portions of said manifold, said igniter means being connected with the inner portion of said manifold, said actuator means being connected with the outer portion of said manifold, at least an end portion of said actuator member being movable through said burst disk into engagement with said igniter means upon movement of said actuator member by said pyrotechnic means.

25. An apparatus as set forth in claim 24 further including housing means for enclosing said body of ignitable material, said housing means being connected with said igniter means which is connected to said inner portion of said manifold, said housing means including surface means for directing a flow of combustion products from said housing means into the chamber in a direction away from said manifold upon burning of said body of ignitable material.

26. An apparatus as set forth in claim 20 further including housing means for enclosing said body of ignitable material, said housing means including an end portion having surface means for defining a first orifice having a first area, an orifice plate disposed in said housing means adjacent to said end portion of said housing means and having a second orifice with a second area which is smaller than the first area, said first and second orifices conducting a flow of combustion products from said housing means during burning of said body of ignitable material, said orifice plate being deformable by the flow of combustion products to increase the size of said second orifice form the second area to an area which is at least approximately as great s the first area.

27. An apparatus for inflating a vehicle occupant restraint, said apparatus comprising:

container means for storing gas under pressure;

a body of ignitable material within said container means;

housing means at least partially disposed within said container means for enclosing said body of ignitable material, said housing means including an end portion having surface means for defining a first orifice having a first area;

igniter means for igniting said body of ignitable material to initiate burning of said body of ignitable material; and

an orifice plate disposed in said housing means between said body of ignitable material and said end portion of said housing means, said orifice plate having surface means for defining a second orifice with a second area which is smaller than the first area to restrict a flow of combustion products from said housing means upon initiation of burning of said body of ignitable material, said first and second orifices conducting a flow of combustion products from said housing means during burning of said body of ignitable material, said orifice plate being deformable by the flow of combustion products to increase the size of said second orifice from the second area to an area which is at least approximately as great as the first area to reduce the extent to which said orifice plate restricts the flow of combustion products from said housing means.

28. An apparatus as set forth in claim 27 further including actuator means for releasing the stored gas from said container means and for actuating said igniter means to ignite said body of ignitable material, said actuator means including an actuator member movable along a path to establish a flow of stored gas from said container means and to actuate said igniter means to ignite said body of ignitable material, and means for moving said actuator member along said path.

29. An apparatus as set forth in claim 27 wherein said igniter means is actuatable in response to being struck to ignite said body of ignitable material, said apparatus further including actuator means for actuating said igniter means to ignite said body of ignitable material, said actuator means including an actuator member which is movable to strike said igniter means and thereby actuate said igniter means to ignite said body of ignitable material, and means for moving said actuator member.

30. An apparatus as set forth in claim 27 wherein said igniter means is actuatable in response to being struck to ignite said body of ignitable material, said apparatus further including actuator means for releasing the stored gas from said container means and for actuating said igniter means to ignite said body of ignitable material, said actuator means including an actuator member, and pyrotechnic means for moving said actuator member to rupture a portion of said container means and to strike said igniter means.

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

container means having a chamber for storing gas under pressure;

a body of ignitable material associated with said container means and which, when ignited, heats said stored gas;

igniter means for igniting said body of ignitable material;

an assembly connected with said container, said assembly including an igniter holder for supporting said igniter means, a manifold member having passage means for directing stored gas from said chamber, and a burst disk closing said passage means; and

means for rupturing said burst disk to enable gas to flow through said passage means and for actuating said igniter means to ignite said body of ignitable material.

32. An apparatus as defined in claim 31 wherein said burst disk has a flange portion which projects between said igniter holder and manifold member and which is welded to said igniter holder and manifold member.

33. An apparatus as defined in claim 31 wherein said igniter holder has a chamber portion in fluid communication with said chamber of said container means and said burst disk blocks fluid communication between said chamber portion and said passage means.

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

container means for storing gas under pressure, said container means including a side wall and having a first opening at a first end portion of said side wall;

housing means for holding a body of ignitable material within said container means; and

a first friction weld interconnecting said housing means and the first end portion of said side wall of said container means.

35. An apparatus as set forth in claim 34 wherein said container means has a second opening at a second end portion of said side wall, plug means for blocking the second opening at the second end portion of said side wall, and a second friction weld interconnecting said plug means and the second end portion of said side wall.

36. An apparatus as set forth in claim 34 wherein said housing means includes a first housing section and a second housing section, said first and second housing sections having passage means for conducting a flow of fluid from said container means, and a burst disk closing said passage means, said apparatus further including actuator means for rupturing said burst disk to enable gas to flow through said passage means.

37. An apparatus as set forth in claim 34 wherein said housing means includes a first section for holding the body of ignitable material in said container means, a second section at least partially disposed outside of said container means, and a burst disk between said first and second housing sections, said apparatus further including actuator means at least partially disposed in said second section of said housing means for rupturing said burst disk to enable gas to flow from said container means and for effecting ignition of the body of ignitable material, said actuator means including an actuator member having an end portion which is movable from said second housing section through said burst disk into said first housing section and pyrotechnic means at least partially disposed in said second housing section for moving said actuator member.

38. An apparatus as set forth in claim 37 wherein said first friction weld interconnects said first end portion of said side wall and said second housing section.