Air bag module with vent controlled by tether

• US 20040051285A1
• Filed: 09/16/2002
• Published: 03/18/2004
• Est. Priority Date: 09/16/2002
• Status: Active Grant

• 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: Fischer, Kurt F.
• Granted Patent: US 7,083,191 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 21/233 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 21/276 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 (12) is inflatable by inflation fluid. A support member (20) has a first vent opening (44) for enabling flow of inflation fluid away from the bag (12). A vent member (46) is movable relative to the first vent opening (44) between a first condition in which the vent member does not close the opening that enables flow of inflation fluid away from the bag (12) and a second condition in which the vent member at least partially blocks the flow of inflation fluid through the opening and away from the bag. A tether (50) has a first portion (52) connected for movement with the bag (12) as the bag is deployed. The tether (50) is associated with the vent member (46) and causes it to move relative to the opening (44) from the first condition to the second condition as the bag (12) is deployed.

Claims

1. A vehicle occupant protection apparatus comprising:

an inflatable vehicle occupant protection device having a deflated condition and an inflated condition to which said vehicle occupant protection device is deployed by inflation fluid;

a support member having a first vent opening for enabling flow of inflation fluid away from said protection device;

a vent member movable relative to said first vent opening between a first condition in which said vent member does not close said first vent opening that enables flow of inflation fluid away from said protection device and a second condition in which said vent member at least partially blocks said flow of inflation fluid through said first vent opening and away from said protection device;

a tether having a first portion connected for movement with said protection device as said protection device is deployed;

said tether being associated with said vent member and causing said vent member to move relative to said first vent opening from the first condition to the second condition as said protection device is deployed.

2. Apparatus as set forth in claim 1 wherein said vent member is a door supported for pivotal movement relative to said first vent opening between the first and second conditions.

3. Apparatus as set forth in claim 2 further including a latch cooperating with said door for maintaining said door in the second condition when said protection device is deployed.

4. Apparatus as set forth in claim 2 wherein said tether is a fabric strap.

5. Apparatus as set forth in claim 4 wherein said tether has a second portion connected with said door for transferring tensile force from said protection device to said door as said protection device is deployed.

6. Apparatus as set forth in claim 1 wherein said tether and said vent member are portions of a single fabric strap.

7. Apparatus as set forth in claim 6 wherein said fabric strap has a second vent opening, said second vent opening being aligned with said first vent opening when said vent member is in the first condition to enable fluid flow from said protection device through said first vent opening, said second vent opening being spaced apart from said first vent opening when said vent member is in the second condition to block fluid flow from said protection device through said first vent opening.

8. Apparatus as set forth in claim 7 wherein said second vent opening is movable relative to said first vent opening between a first position when said device is in the inflated condition in which said second vent opening is aligned with said first vent opening, and a second position when said device is in the inflated condition in which said second vent opening is not aligned with said first vent opening.

9. Apparatus as set forth in claim 1 wherein said first portion of said tether includes a first part of said tether connected for movement with said protection device at a first location and a second part of said tether connected for movement with said protection device at a second location spaced apart from said first location;

said first and second parts of said tether moving away from said vent member upon inflation of said protection device,

said tether causing said vent member to move relative to said first vent opening from the first condition to the second condition when said protection device is deployed in a manner that the combined distances between said first part of said tether and said vent member and between said second part of said tether and said vent member substantially equal the length of said tether between said first and second parts.

10. Apparatus as set forth in claim 9 wherein said tether has an intermediate portion between said first and second parts that is movable around a portion of said vent member to vary the distance between said first part of said tether and said vent member in inverse relationship to the distance between said second part of said tether and said vent member.

11. Apparatus as set forth in claim 1 wherein said tether causes said vent member to move relative to said first vent opening from the first condition to the second condition to close said first vent opening only in response to movement of first and second portions of said protection device away from said vent door by a combined amount in excess of a predetermined amount.

12. Apparatus as set forth in claim 1 wherein said tether has slack when said protection device is in a deflated condition due to the length of said tether being greater than the distance between its opposite ends when said protection device is in the deflated condition, said tether being tensioned upon inflation of said protection device beyond a predetermined amount to remove said slack from said tether to cause said vent member to move relative to said first vent opening from the first condition to the second condition to close said first vent opening.