Variable venting air bag assembly

• US 20030020266A1
• Filed: 07/05/2002
• Published: 01/30/2003
• Est. Priority Date: 07/12/2001
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Delphi Technologies, Inc. (Aptiv PLC)
• Inventors: Ryan, Shawn Gregory, Vendely, Michael Joseph, Schenck, Michael Allen
• Granted Patent: US 6,648,371 B2
• Time in Patent Office: Days
• US Class Current: 280/739
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 2021/2765 comprising means to control the venting
• CPC Class Codes: B60R 21/217 Inflation fluid source retainers, e.g. reaction canisters; Connection of bags, covers, diffusers or inflation fluid sources therewith or together
• 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

Abstract

An air bag assembly having an inflatable cushion selectively deployable to a controlled geometry with a controlled venting character. The venting characteristics are adjusted by selective displacement of vent blocking elements based upon measured occupant and/or crash severity characteristics such that an air bag cushion of desired volume and venting capacity is available to protect a range of occupants under different conditions during impact events of various levels of severity.

Claims

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

an inflatable air bag cushion having at least one vent opening;

an inflator activatable to discharge inflation gas upon the occurrence of predetermined vehicle conditions;

a displaceable vent blocking element supported at a surface of the air bag cushion and normally disposed in blocking relation to said at least one vent opening so as to at least partially obstruct the passage of inflation gas through to said at least one vent opening, wherein the vent blocking element is operatively connected to a releasable anchor structure such that the vent blocking element is normally held in tension when the air bag cushion is inflated; and

an actuation mechanism selectively activatable based upon measurements from one or more sensors measuring conditions of the occupant to release the vent blocking element from the releasable anchor structure when increased venting capacity is desired, and wherein the vent blocking element is adapted to at least partially open said at least one vent opening when the vent blocking element is released from the releasable anchor structure.

2. The safety system according to claim 1, wherein the vent blocking element comprises an elongate patch of pliable material.

3. The safety system according to claim 2, wherein the elongate patch is secured at a first end to an exterior surface of the air bag cushion and is threaded in sliding relation through said at least one vent opening to an interior region of the air bag cushion so as to at least partially block said at least one vent opening when the elongate patch is held in tension.

4. The safety system according to claim 3, wherein a tear-away seam is disposed between the elongate patch and an interior surface of the air bag cushion at a location between said at least one vent opening and said releasable anchor structure such that the elongate patch is normally held in position in threaded relation across said at least one vent opening and wherein the tear-away seam is adapted to fail when the elongate patch is disengaged from the releasable anchor and pressure within the air bag cushion exceeds a predefined level.

5. The safety system according to claim 3, wherein the elongate patch is formed of fabric.

6. The safety system according to claim 1, wherein the vent blocking element comprises an elongate patch of pliable material and wherein the elongate patch is secured at a first end to a surface of the air bag cushion and extends in covering relation over a plurality of vent openings within the air bag cushion so as to block at least a portion of said vent openings when the elongate patch is held in tension between said first end and the releasable anchor structure.

7. The safety system according to claim 6, wherein a pattern of tear away seams extends at least partially along the length of the elongate patch in connecting relation between the elongate patch and a surface of the air bag cushion in outboard relation to said vent openings and wherein the tear-away seams are adapted to fail when the elongate patch is disengaged from the releasable anchor and pressure within the air bag cushion exceeds a predefined level.

8. The safety system according to claim 7, wherein the tear-away seams are adapted to progressively fail in a predefined path extending from a position remote from the first end of the elongate patch towards the first end of the elongate patch as pressure within the air bag cushion is increased.

9. The safety system according to claim 6, wherein the elongate patch is formed of fabric.

15. The safety system according to claim 1, wherein the air bag cushion is a driver side air bag cushion comprising two panels seamed around their perimeters.

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

an inflatable air bag cushion having at least one vent opening;

an inflator activatable to discharge inflation gas upon the occurrence of predetermined vehicle conditions;

a displaceable vent blocking element comprising an elongate nozzle of collapsible construction supported at a surface of the air bag cushion in surrounding relation to said at least one vent opening;

an elongate tethering element operatively connected between the nozzle and a releasable anchor structure such that the nozzle is normally held in tension when the air bag cushion is inflated so as to at least partially obstruct the passage of inflation gas through the nozzle to said at least one vent opening; and

an actuation mechanism selectively activatable based upon measurements from one or more sensors measuring conditions of the occupant to release the tethering element so as to relieve tension across the nozzle and open the nozzle for passage of gas out of the air bag cushion.

11. The safety system according to claim 10, wherein the nozzle is integral to the air bag cushion.

12. The safety system according to claim 10, wherein the nozzle is attached across a surface of the air bag cushion facing substantially away from the occupant to be protected.

13. The safety system according to claim 10, wherein the nozzle comprises a tubular construction formed from one piece of material enclosed by an elongate seam.

14. The safety system according to claim 10, wherein the nozzle comprises a hollow construction formed from a plurality of pieces of material enclosed by a plurality of seams.

16. The safety system according to claim 10, wherein the air bag cushion is a driver side air bag cushion comprising two panels seamed around their perimeters.