Patent ID: 7854477

Claim:
A seat back support mechanism for supporting the back of a seat in a motor vehicle relative to a squab of the seat, the seat back support mechanism comprising: at least one external support plate adapted to be interconnected to the squab; a support arm adapted to be connected to the back of the seat; and a linkage interconnecting the at least one support arm to the at least one external support plate for relative motion therebetween the linkage including two pivot link elements and an intermediate support plate the intermediate support plate at least indirectly coupled to the at least one external support plate, defining an opening and including a deformable structure disposed adjacent the opening, the pivot link elements moveable relative to the intermediate support plate, the pivot link elements each being mounted to effect pivotal movement of the intermediate support plate relative to the at least one external support plate, the pivot link elements at least indirectly supporting the support arm, the linkage further including a member at least indirectly coupled to the support arm, the member moveable in response to movement of the support arm, the member normally received within the opening of the intermediate member and moveable into engagement with the deformable structure to deform the deformable member in response to a force in excess of a predetermined threshold; whereby the linkage normally permits rearward tilting of the back of the seat and the linkage prevents rearward movement of the back of the seat in response to the force in excess of predetermined threshold.