Air bag module with vent controlled by tether
View Patent ↗A vehicle occupant protection apparatus ( 10 c ) has an inflatable occupant protection device ( 12 c ) and a support member ( 20 c ) having a vent opening ( 44 c ). A vent member ( 46 c ) is associated with the vent opening ( 44 c ). A tether ( 50 c ) extends between the protection device ( 12 c ) and the vent member ( 46 c ). The vent member ( 46 c ) is initially in a first condition closing the vent opening ( 44 c ). The vent member ( 46 c ) is moved to a second condition spaced apart from the vent opening ( 44 c ) and enabling fluid flow through the vent opening ( 44 c ) upon initial inflation of the protection device ( 12 c ). The vent member ( 46 c ) is moved from the second condition back toward the first condition by tension in the tether ( 50 c ) that results from inflation of the protection device ( 12 c ) away from the support member ( 20 c ) by more than a predetermined distance.
1. A vehicle occupant protection apparatus comprising:
an inflatable vehicle occupant protection device;
a support member having a vent opening;
a vent member associated with the vent opening and having a first condition in which the vent member closes the vent opening and a second condition in which the vent member is spaced apart from the vent opening enabling fluid flow through the vent opening; and
a tether extending between the protection device and the vent member,
the vent member initially being in the first condition and being moved from the first condition to the second condition for enabling a flow of inflation fluid through the vent opening upon initial inflation of the protection device, the vent member being moved from the second condition back toward the first condition by tension in the tether that results from inflation of the protection device away from the support member by more than a predetermined distance.
2. The apparatus of claim 1 wherein the vent member includes a living hinge for enabling bending of the vent member, the vent member being bent at the living hinge when moving from the first condition to the second condition.
3. The apparatus of claim 1 wherein the vent member includes a material stiffness that is sufficient for preventing movement of the vent member from the first condition to the second condition as a result of vibrations.
4. The apparatus of claim 1 wherein the vent member includes a first portion that is secured to the support member and a second portion that moves relative to the support member and the first portion of the vent member for moving the vent member between the first and second conditions.
5. The apparatus of claim 1 wherein the vent member includes a slot, the tether extending through the slot of the vent member from a first surface of the vent member to a second surface of the vent member, the tether, when tensioned, acting on the second surface of the vent member for moving the vent member from the second condition back toward the first condition.
6. The apparatus of claim 1 further including a cover that is supported by the support member and that defines a chamber in which the protection device is stored prior to being inflated, the cover including a tear seam that ruptures for enabling the protection device to expand outward of the chamber, the vent member being moved from the first condition to the second condition prior to the tear seam of the cover rupturing.
7. The apparatus of claim 1 further including an inflator that is actuatable for providing inflation fluid for inflating the protection device, the support member supporting the inflator, inflation fluid resulting from actuation of the inflator acting upon the vent member to move the vent member from the first condition to the second condition.
8. The apparatus of claim 1 wherein the vent opening, the vent member, and the tether are a first vent opening, a first vent member, and a first tether, respectively, the support member also including a second vent opening that is spaced apart from the first vent opening, a second vent member associated with the second vent opening and also having a first condition in which the second vent member closes the second vent opening and a second condition in which the second vent member is spaced apart from the second vent opening enabling fluid flow through the second vent opening, a second tether extending between the protection device and the second vent member, the second vent member initially being in the first condition and being moved from the first condition to the second condition for enabling a flow of inflation fluid through the second vent opening upon initial inflation of the protection device, the second vent member being moved from the second condition back toward the first condition by tension in the second tether that results from inflation of the protection device away from the support member by more than the predetermined distance.
9. The apparatus of claim 8 wherein the first and second vent openings are located at diametrically opposite positions in the support member.
10. The apparatus of claim 8 wherein the first and second tethers operate independently of one another for closing the first and second vent members, respectively.
11. The apparatus of claim 8 further including an inflator that is actuatable for providing inflation fluid for inflating the protection device, the support member supporting the inflator, inflation fluid resulting from actuation of the inflator acting upon the first vent member to move the first vent member from the first condition to the second condition, inflation fluid resulting from actuation of the inflator also acting upon the second vent member to move the second vent member from the first condition to the second condition.