Air bag in use for head protection air bag device

摘要

An air bag is stored along the peripheral edge of the upper fringe of an opening on the indoor side in a state that it is covered with a door of an air bag cover and folded. When receiving inflation gas, the air bag forcibly opens the door and develops and inflates downward so as to cover the opening. In a region of an inflating section to which gas for inflation flows, a plurality of thickness defining members, which couple the cabin-inside side wall with the cabin-outside side wall to make a thickness of the inflating section uniform, are arranged side by side in the front/rear direction, while extending in the vertical direction. The thickness defining member disposed near the unsmooth development part of the door is disposed such that the upper end thereof is located at a position lower than the upper end of the thickness defining member.