Patent attributes
An airbag includes plural bag portions respectively including two sheet members attached to each other, and a welded portion at which the sheet members being in contact with each other are attached to each other. The welded portion includes a communication hole penetrating the sheet members to communicate the bag portions, and a rib portion arranged radially outward of the communication hole, the rib portion protruding in the thickness direction from a welded surface of the welded portion. The rib portion includes an annular rib surrounding the communication hole, and a cutout portion provided at the annular rib. The rib portion includes plural radial ribs arranged radially inward of the annular rib, the plural radial ribs radially surrounding the communication hole and extending in a radial direction of the communication hole. At least one of the radial ribs is arranged at a position radially away from the communication hole.
