Patent ID: 7857347

Claim:
An airbag device to be deployed by gas supplied from an inflator for restraining an occupant, comprising: an outer shell forming an airbag and having a vent hole and a through hole smaller than the vent hole, said through hole being located adjacent to the vent hole; a restriction member for restricting gas flow through the vent hole; an inner panel partitioning an inside of the airbag into a first chamber located at a side opposite to the occupant and a second chamber located at a side of the occupant, and having a peripheral edge connected to a side periphery of the airbag and a communication portion for allowing communication between the first chamber and the second chamber, the vent hole being provided in the first chamber; and a tether member for connecting said restriction member and the inner panel, said tether member extending through the through hole and being connected to the restriction member at a location external of the outer shell, said airbag device being arranged such that: as the inflator starts its operation, the gas is first introduced into the first chamber and is then introduced into the second chamber through the communication portion, when the first chamber is filled with the gas and the inner panel is tensioned by a pressure differential between the first chamber and the second chamber, a tension exceeding a predetermined value is applied to said restriction member via the tether member so that said vent hole is substantially closed, and when the first chamber is not filled with the gas and the inner panel loosens, the tension applied to said restriction member does not reach the predetermined value so that said vent hole is substantially opened.