Patent ID: 7878542

Claim:
An airbag device comprising: an airbag to be inflated and deployed toward a passenger by high-pressure gas ejected from an inflator upon a vehicle collision; an inner pressure adjusting unit provided on the airbag and capable of adjusting an aperture efficiency of at least one vent hole in plural steps according to a deploying state of the airbag; a tether belt whose one end is connected to the inner pressure adjusting unit; and a holding unit for hooking another end of the tether belt and capable of releasing the other end of the tether belt, wherein, in a case where the inflating airbag needs to exert a small reactive force, the inner pressure adjusting unit is made in a full-opened state at a development early stage of the airbag with the other end of the tether belt being held by the holding unit and then the inner pressure adjusting unit is made in a half-opened state until a development final stage of the airbag with the other end of the tether belt being kept held by the holding unit, and, in a case where the inflating airbag needs to exert a large reactive force, the inner pressure adjusting unit is made in a full-closed state from a development start to the development final stage of the airbag with the other end of the tether belt being released from the holding unit.