Head protection air bag system

A head protection air bag system comprising an air bag accommodated on an upper edge side of a window with an upper edge side thereof which results when the air bag is completely inflated connected to a body side member on the upper edge side of the window on an inner side of a vehicle and adapted to be inflated by an inflation gas being caused to flow into an interior thereof to project downwards from the upper edge side of the window so as to cover the side of the window which faces the inner side of the vehicle,

• the air bag comprising:
• an inflatable shield portion which covers the side of the window which faces the inner side of the vehicle when the air bag is completely inflated;
• and
• an edge side shield portion disposed on a front or rear edge portion side of the inflatable shield portion, accommodated in an area of a pillar portion which extends obliquely downwards from the upper edge side of the window at a front or rear edge portion side of the window when the air bag is folded for accommodation with an upper edge thereof made to be inclined so as to match the inclination of the pillar portion when the edge side shield portion is deployed flat, and made to cover an area of the window which lies on a lower side of the pillar portion on the side facing the inner side of the vehicle when the air bag is inflated completely,
• the edge side shielding portion being disposed on the upper edge side when the air bag is inflated completely and being made to be mounted on a body side member at the pillar portion at a first mounting portion which is positioned on the inflatable shield portion side and a second mounting portion which lies closer to an end side in a front-rear direction and further downwards than the first mounting portion,
• in a completely folded body formed by folding the air bag such that a lower edge approaches the upper edge while forming folds extending substantially along the front-rear direction, an edge side folded portion which is formed by folding the edge side shield portion so as to be continued from the upper edge of the inflatable shield portion in a straight line in the front-rear direction being made to be accommodated in an interior of the pillar portion, wherein
• an auxiliary mounting portion that is to be fastened together with the second mounting portion is provided in a position where the edge side shield portion coincides with the second mounting portion in its front-rear position and coincides with the first mounting portion in its up-down position above the second mounting portion with the air bag deployed flat, wherein
• the auxiliary mounting portion is disposed on a distal end side of an extension which extends in a straight line from the first mounting portion, and wherein
• a portion lying between the second mounting portion and the first mounting portion on the upper edge side of the side edge shield portion is connected to the extension by a connecting portion.