Patent 8727378 was granted and assigned to Takata Corporation on May, 2014 by the United States Patent and Trademark Office.
In an air bag main body which inflates step by step in a first stage and a second stage by bonding its peripheral edge portion and bonding its inner side than the peripheral edge portion, a connecting member bridging between a lid member opening and closing a vent hole and a coupling member can be always set to a tension state by arranging an adjusting portion in the coupling member which defining a maximum facing distance between a front panel and a rear panel in the tension state in each of the first stage and the second stage, and whereby a closed state of the vent hole can be maintained.