Air bag module with vent controlled by tether

• US 7,377,546 B2
• Filed: 01/28/2005
• Issued: 05/27/2008
• Est. Priority Date: 09/16/2002
• 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: Fischer, Kurt F., Braun, William P., Zwolinski, Joseph J., Wallner, John P., Meduvsky, Alex G.
• Primary Examiner(s): Ilan; Ruth
• Assistant Examiner(s): Sliteris; Joselynn Y.
• Application Number:
  US11/046,180
• Publication Number:
  US 20050127648A1
• Time in Patent Office: 1,215 Days
• Field of Search: 280/739, 280/743.2, 280/736, 280/742
• US Class Current: 280/739
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 2021/23384 having ends which are movable or detachable during deployment
• 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 21/2171 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 21/276 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

A vehicle occupant protection apparatus (10d) includes an inflatable occupant protection device (300) and a support member (316). A vent opening (350) extends through the support member (316). A vent member (360) is associated with the vent opening (350). The vent member (360) initially closes the vent opening (350). Inflation fluid moves the vent member (360) relative to the support member (316) for enabling a flow of inflation fluid through the vent opening (350). A tether (386) extends between the inflatable occupant protection device (300) and the vent member (360). The tether (386) is responsive to inflation of the inflatable occupant protection device (300) away from the support member (316) by more than a predetermined distance for moving the vent member (360) relative to the support member (316) for reducing the flow of inflation fluid through the vent opening (350).

Claims

1. A vehicle occupant protection apparatus comprising:

an inflatable occupant protection device;

a support member having a vent opening extending through the support member;

an inflator that is actuatable for providing inflation fluid for inflating the inflatable occupant protection device;

a vent member associated with the vent opening, the vent member initially closing the vent opening, inflation fluid provided by the inflator moving the vent member relative to the support member for enabling a flow of inflation fluid through the vent opening; and

a tether extending between the inflatable occupant protection device and the vent member, the tether being responsive to inflation of the inflatable occupant protection device away from the support member by more than a predetermined distance for moving the vent member relative to the support member for reducing the flow of inflation fluid through the vent opening.

2. The vehicle occupant protection apparatus of claim 1 wherein the vent member includes a living hinge, a first portion of the vent member being attached to the support member and a second portion of the vent member being pivotal relative to the support member, the living hinge connecting the first and second portions of the vent member.

3. The vehicle occupant protection apparatus of claim 1 wherein the vent member is connected to the support member with a hinge that enables pivotal movement of the vent member relative to the support member.

4. The vehicle occupant protection apparatus of claim 3 wherein the hinge includes first and second portions, the first portion of the hinge being attached to the vent member and the second portion of the hinge being attached to a spacer block at a location adjacent the vent opening.

5. The vehicle occupant protection apparatus of claim 3 wherein the vent member is formed as one piece with the support member and not from separate pieces secured together, the hinge being a living hinge formed in the support member.

6. The vehicle occupant protection apparatus of claim 5 wherein the living hinge is formed from a thinned portion of the support member.

7. The vehicle occupant protection apparatus of claim 6 wherein material properties of the support member and a thickness of the support member at the living hinge may be adjusted for controlling when inflation fluid moves the vent member to enable the flow of inflation fluid through the vent opening.

8. The vehicle occupant protection apparatus of claim 1 wherein the vent member is in a first condition when closing the vent opening, inflation fluid moving the vent member from the first condition to a second condition, the vent member, when in the second condition, being positioned relative to the support member so that a flow area between the vent member and the support member is equal to or greater than a flow area of the vent opening.

9. The vehicle occupant protection apparatus of claim 8 wherein the vent member is rectangular and is pivotable relative to the support member, an angle of the vent member relative to the support member satisfying the equation, V≦

L sin(B)(W+L cos(B)), wherein V is the flow area of the vent opening, W is a width of the vent member, L is a length of the vent member, and B is the angle of the vent member relative to the support member.

10. The vehicle occupant protection apparatus of claim 8 wherein the tether has a length that returns the vent member to the first condition prior to the inflatable occupant protection device reaching a fully expanded condition.

11. The vehicle occupant protection apparatus of claim 10 wherein the length of the tether and a location at which the tether is attached to the inflatable occupant protection device control the timing, during inflation of the inflatable occupant protection device, at which the vent member returns to the first condition.

12. The vehicle occupant protection apparatus of claim 10 wherein the tether creates a dimple on an outer panel of the inflatable occupant protection device when the inflatable occupant protection device is in the fully expanded condition.

13. The vehicle occupant protection apparatus of claim 10 wherein the tether includes a loop that is formed by stitching together two portions of the tether, stitching of the loop being designed to tear when the tether is subjected to a predetermined tension.

14. The vehicle occupant protection apparatus of claim 1 wherein a portion of the inflatable occupant protection device, when in a folded and stored condition, covers the vent opening.

15. The vehicle occupant protection apparatus of claim 14 wherein inflation fluid provided by the inflator is directed against the inflatable occupant protection device, when in the folded and stored condition, for moving the inflatable occupant protection device away from the vent opening.

16. The vehicle occupant protection apparatus of claim 1 further including a tether guide member for guiding the tether between the inflatable occupant protection device and the vent member.

17. The vehicle occupant protection apparatus of claim 16 wherein the tether guide member is formed as one piece with the support member and not from separate pieces secured together.

18. The vehicle occupant protection apparatus of claim 17 wherein the support member defines a chamber, a portion of the support member being bent into the chamber to form the tether guide member.

19. The vehicle occupant protection apparatus of claim 16 wherein the tether guide member includes a curved guide surface over which the tether, when tensioned, is redirected.

20. The vehicle occupant protection apparatus of claim 1 further including a cover that is attached to the support member, the cover including an outer panel having a tear seam that, when ruptured, enables inflation of the inflatable occupant protection device away from the support member, inflation fluid moving the vent member to enable the flow of inflation fluid through the vent opening prior to the tear seam of the cover rupturing.

21. The vehicle occupant protection apparatus of claim 1 further including a tether locking member for preventing movement of an end of the tether and the vent member away from the support member.

22. The vehicle occupant protection apparatus of claim 21 wherein the tether locking member is a resilient, one-piece structure secured to the support member.

23. The vehicle occupant protection apparatus of claim 22 wherein the tether locking member includes a first portion and a second portion oriented at an obtuse angle relative to the first portion.

24. The vehicle occupant protection apparatus of claim 23 wherein the second portion of the tether locking member bends in order to enable closing of the vent opening by the vent member.

25. The vehicle occupant protection apparatus of claim 1 further including a locking member for, along with the tether, limiting movement of the vent member away from the vent opening.