Air bag with improved tear stitch

An apparatus for helping to protect an occupant of a vehicle, the apparatus comprising:

• an inflatable vehicle occupant protection device having a deflated condition and an inflated condition;
• and
• tear stitching interconnecting overlying first and second fabric portions of the protection device, the tear stitching being rupturable to permit the interconnected portions to move relative to each other, the tear stitching comprising a break point and first and second segments that extend away from the break point, a non-stitched portion of the second fabric portion that is free from stitching being folded back to overlie a stitched portion of the second fabric portion, the folded back portion forming a fold positioned adjacent the break point, the first and second fabric portions being configured such that tension on the second fabric portion creates a peeling action whereby the folded back portion being free from stitching is free to move relative to and be pulled along the stitched portion so that the fold moves toward the break point in order to focus tension forces acting to rupture the tear stitching on the fold and primarily on the break point so that the tear stitching ruptures first at the break point and then along the first and second segments of the tear stitching, wherein the interconnected portions of the protection device comprise a vent door and a panel of the protection device that includes at least one vent opening, the tear stitching being rupturable to permit the vent door to move relative to the panel to release inflation fluid to vent out of the protection device.

An apparatus for helping to protect an occupant of a vehicle, the apparatus comprising:

• an inflatable vehicle occupant protection device having a deflated condition and an inflated condition;
• and
• first tear stitching interconnecting a vent door and a panel of the protection device, the first tear stitching being rupturable to permit the vent door to move relative to the panel;
• second tear stitching interconnecting portions of the protection device to maintain the protection device in a first inflated condition with a first inflated volume, the second tear stitching being rupturable to release the interconnected portions to allow the protection device to inflate to a second inflated condition with an increased second inflated volume;
• each of the first and second tear stitching comprising a break point and first and second segments that extend away from the break point, the configurations of the first and second tear stitching being selected such that the magnitude of the tension required to rupture the first tear stitching is less than the magnitude of the tension required to rupture the second tear stitching.