Patent ID: 6860505

Claim:
An airbag device for a vehicle, comprising an interior cover of the vehicle having a rectangular fracture-opening section defined by means of fragile sections which are constituted by fracture grooves formed on a back side of said interior cover; an airbag case placed under said interior cover and adapted to accommodate an inflatable airbag element in a folded form, said airbag case having an opening which faces said fracture-opening section of said interior cover; a reinforcement plate having a shape corresponding to said fracture-opening section; and a reinforcement rib extending downwards from the back side of said interior cover and having a rectangular cross section corresponding to said fracture-opening section, wherein mounting holes are formed in front and rear side walls of said reinforcement rib at predetermined intervals along a longitudinal direction of said reinforcement rib; hooks firmly mounted to front and rear side walls of said airbag case at predetermined intervals along a longitudinal direction of said airbag case are engaged with said mounting holes, while passing through corresponding mounting sections extending from said reinforcement plate via corresponding hinges of said reinforcement plate; a left side wall of said reinforcement of rib is separated from a left side wall of said airbag case by a predetermined distance, and a right side wall of said reinforcement ribs is separated from a right side wall of said airbag case by a predetermined distance; one fracture groove partially defining said fracture-opening section is located between the left side wall of said reinforcement rib and the left side wall of said airbag case, and another fracture groove partially defining said fracture-opening section is located between the right side wall of said reinforcement rib and the right side wall of said airbag case; and wherein said fracture groove and said another fracture groove are formed in positions spaced from said left side wall of said reinforcement rib and said right side wall of said reinforcement rib respectively such that the rectangular fracture-opening section of the interior cover can absorb shearing stress by deformation of said rectangular fracture-opening section just before inflation of the inflatable airbag element.