Air bag restraint including selectively operable venting elements

• US 20040012180A1
• Filed: 02/24/2003
• Published: 01/22/2004
• Est. Priority Date: 07/19/2002
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Winters, Mark Thomas, Pinsenschaum, Ryan Todd, Hawthorn, Laura Adelle, Dunkle, Stephanie L.
• Granted Patent: US 6,932,385 B2
• Time in Patent Office: Days
• US Class Current: 280/739
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 2021/2765 comprising means to control the venting
• 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 21/233 comprising a plurality of individual compartments; comprising two or more bag-like members, one within the other B60R21/232 takes precedence
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/2342 Tear seams
• CPC Class Codes: B60R 21/239 characterised by their venting means
• 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 air bag safety system for cushioning restraint of a vehicle occupant during an impact event. The safety system includes a variable depth inflatable air bag cushion inflated by a gas emitting inflator within an inflator housing. A cover element of substantially pliable material is located in adjustable relation to a vent opening across a wall of the housing. The cover element is selectively displaceable relative to the vent opening in response to the inflation depth of the air bag cushion so as to adjust venting characteristics across the housing.

Claims

1. An air bag safety system for cushioning restraint of a vehicle occupant during an impact event, the safety system comprising:

a variable depth inflatable air bag cushion adapted to be selectively inflatable to one of a first depth and at least a second depth greater than the first depth;

a gas emitting inflator disposed within a walled housing, wherein said walled housing includes at least one vent opening; and

a displaceable vent blocking cover element of substantially pliable material supported at a surface of said walled housing, wherein the cover element is adjustable from a first operative position relative to the vent opening when the air bag cushion is inflated to said first depth and to at least a second different operative position relative to the vent opening when the air bag cushion is inflated to said second depth so as to vary emission of inflation gas through said at least one vent opening in a predefined manner based upon the depth of inflation of the air bag cushion.

2. The safety system according to claim 1, further comprising at least one sensor for measuring at least one condition of the vehicle occupant, wherein said at least one condition is selected from the group consisting of occupant volume, occupant mass, occupant position and combinations thereof and wherein the air bag cushion is selectively inflatable to one of the first depth or the second depth based upon measurement of said at least one condition.

3. The safety system according to claim 1, wherein the cover element is disposed at the interior of said walled housing.

4. The safety system according to claim 1, further comprising a variable inflation device adapted to adjust the volume of inflation gas delivered to the air bag cushion such that a first volume of inflation gas is delivered into the air bag cushion when the air bag cushion is inflated to the first depth and a second greater volume of inflation gas is delivered into the air bag cushion when the air bag cushion is inflated to the second depth.

5. The safety system according to claim 1, wherein the cover element is operatively attached to at least one elongate tensioning strap extending in operative relation between the cover element and a shape defining tethering element operatively connected to a surface of the air bag cushion.

6. The safety system according to claim 1, wherein the cover element comprises a panel of pliable material including at least a first pleat structure normally disposed outboard of said at least one vent opening such that upon the application of tension across the cover element a portion of the cover element forming the first pleat structure is shifted at least partially over said at lest one vent opening.

7. The safety system according to claim 6, wherein the cover element includes a cut out portion defining an opening normally disposed in at least partial alignment with said at least one vent opening and wherein said cut out portion is moved out of alignment with said at least one vent opening when the portion of the cover element forming the first pleat structure is shifted at least partially over said at least one vent opening.

8. An air bag safety system for cushioning restraint of a vehicle occupant during an impact event, the safety system comprising:

a variable depth inflatable air bag cushion adapted to be selectively inflatable to one of a first depth or a second depth greater than the first depth;

a gas emitting inflator disposed within a walled housing, wherein said walled housing includes at least one vent opening; and

a cover element of substantially pliable material disposed in sliding relation relative to the vent opening, the cover element including a vent blocking portion normally disposed within a first folded pleat structure outboard of the vent opening, the cover element further including an aperture normally disposed within a second folded pleat structure outboard of the first folded pleat structure such that the first folded pleat structure is normally disposed between the second folded pleat structure and the vent opening, the cover element being operatively connected to the air bag cushion such that when the air bag cushion is uninflated or is restrained to an inflation depth less than said first depth, the cover element remains in its normal position with the blocking portion disposed within the first folded pleat structure outboard of the vent opening and such that upon inflation of the air bag cushion to the first depth the cover element is placed into tension thereby shifting the vent blocking portion at least partially over the vent opening without collapsing the second folded pleat structure and such that upon inflation of the air bag cushion to the second depth the aperture within the second folded pleat structure is moved at least partially over the vent opening.

9. The safety system according to claim 8, further comprising at least one sensor for measuring at least one condition of the vehicle occupant, wherein said at least one condition is selected from the group consisting of occupant volume, occupant mass, occupant position and combinations thereof and wherein the air bag cushion is selectively inflatable to one of the first depth or the second depth based upon measurement of said at least one condition.

10. The safety system according to claim 8, wherein the cover element is operatively attached to the air bag cushion by at least one elongate tensioning strap extending between the cover element and at least one shape defining tethering element supported at a surface of the air bag cushion.

11. The safety system according to claim 8, wherein the cover element includes a cut out portion defining an opening normally disposed in at least partial alignment with said at least one vent opening and wherein said cut out portion is moved out of alignment with said at least one vent opening when the vent blocking portion of the cover element forming the first pleat structure is shifted at least partially over said at least one vent opening.

12. An air bag safety system for cushioning restraint of a vehicle occupant during an impact event, the safety system comprising:

at least one sensor for measuring at least one occupant specific condition during the impact event;

a variable depth inflatable air bag cushion adapted to be selectively inflatable to one of a first depth or a second depth greater than the first depth based upon a measurement from said at least one sensor;

a gas emitting inflator disposed within a walled housing, wherein the inflator is adapted to release a volume of inflation gas upon activation of a first initiator;

an actuatable variable inflation device adapted to vary the volume of inflation gas discharged into the air bag cushion, wherein the variable inflation device comprises a moveable member alignable with a first vent opening within the housing, the moveable member being moveable relative to the vent opening upon activation of a second initiator thereby adjusting the effective venting area of the first vent opening; and

a cover element of substantially pliable material disposed in sliding relation relative to a second vent opening, the cover element including a cut out portion defining an opening normally disposed in at least partial alignment with said second vent opening, the cover element further including a vent blocking portion normally disposed within a first folded pleat structure outboard of said second vent opening, the cover element being operatively connected to the air bag cushion such that when the air bag cushion is uninflated or is restrained to an inflation depth less than said first depth, the cover element remains in its normal position with the cut out portion disposed in at least partial alignment with said second vent opening and the vent blocking portion disposed within the first folded pleat structure outboard of the vent opening and such that upon inflation of the air bag cushion to the first depth the cover element is placed into tension thereby shifting the vent blocking portion at least partially over said second vent opening.

13. The safety system according to claim 12, wherein the cover element is operatively attached to the air bag cushion by at least one elongate tensioning strap extending between the cover element and at least one shape defining tethering element supported at a surface of the air bag cushion.

14. The safety system according to claim 12, wherein the cover element further includes an aperture normally disposed within a second folded pleat structure outboard of the first folded pleat structure such that the first folded pleat structure is normally disposed between the second folded pleat structure and the second vent opening such that upon inflation of the air bag cushion to the first depth the cover element is placed into tension thereby shifting the vent blocking portion at least partially over the second vent opening without collapsing the second folded pleat structure and such that upon inflation of the air bag cushion to the second depth the aperture within the second folded pleat structure is moved at least partially over the second vent opening.

15. The safety system according to claim 12, wherein the first initiator and the second initiator comprise pyrotechnic squib elements.

16. The safety system according to claim 15, comprising no more than two pyrotechnic squib elements.