Patent ID: 7401811

Claim:
An airbag device having an airbag, the airbag comprising first and second base cloths sewn at their outer peripheries, and inflated by supplying gas generated by an inflator to the inside of the airbag through a central portion of one base cloth upon collision of a vehicle, wherein the first and second base cloths are joined by a bonding portion continuously extending in a generally circumferential direction from the central portion towards the outer periphery, wherein load caused by inflation of the airbag breaks the bonding portion from the central portion towards the outer periphery, wherein thread used to sew the outer peripheries of the first and second base cloths is thicker and stronger than a breakaway thread used to sew the bonding portions between the first and second cloths, and wherein a radially inner end of the bonding portion has a separation strength larger than that of a remainder of the bonding portion.