US Patent 7377540 Airbag unit and case of airbag unit

A case of an airbag unit has a case body for forming a storage room for accommodating an airbag. The case body has a bottom section, a pair of first side walls, and a pair of second side walls. The case also has a movable component disposed adjacent to an outer surface of one of the first side walls, and retractable toward a base end along the case body in response to an external force applied to the case. One of the first side walls has a plurality of pillars extending upwardly from the bottom to form cut-off portions therebetween extending downwardly from the upper opening.