Patent ID: 7600782

Claim:
An airbag apparatus comprising: an airbag inflatable with inflation gas from a folded and housed state, the airbag including an exhaust hole that is formed through a circumferential wall of the airbag in such a manner as to be opened at any time for emitting part of inflation gas; an open/close controller for controlling opening and closing operations of the exhaust hole; a flap element foldable together with the airbag, the flap element being releasably joined to the open/close controller and being joined to a periphery of the exhaust hole in an outer side of the airbag which periphery is in a side facing away from the open/close controller, upon airbag inflation if the flap element is retained by the open/close controller, the flap element holding down a circumference of the exhaust hole, and if the flap element is released from the open/close controller, the flap element opening by a pressure of inflation gas to open the exhaust hole; and an inner flap acting as an open/close means and joined to the periphery of the exhaust hole on the outer side of the airbag in a foldable manner, the inner flap, upon airbag inflation, if the flap element is retained by the open/close controller, being held down at an outer side thereof by the flap element to keep the exhaust hole closed, and if the flap element is released from the open/close controller, opening around a first joint portion joining the inner flap to the airbag due to the pressure of inflation gas such that the exhaust hole opens to exhaust inflation gas, wherein: the first joint portion of the inner flap is located opposite from a second joint portion that joins the flap element to the airbag with respect to the exhaust hole; both of the first joint portion and the second joint portion are bent in shape such that opposite ends thereof are directed toward the other joint portion; and the two joint portions enclose the exhaust hole thoroughly.