Patent ID: 7073854

Claim:
A motor vehicle seat, comprising: a driver seat portion disposed at a front portion of the motor vehicle seat; a passenger seat portion disposed immediately behind the driver seat portion, the passenger seat portion having a front end, a rear end, and a width that is reduced gradually from the front end to the rear end; and a back supporting device comprising: a pair of hollow left and right sliding rails disposed respectively and fixedly on two opposite sides of the passenger seat portion such that said left and right sliding rails extend from the front end of the passenger seat portion to the rear end of the passenger seat portion, said left and right sliding rails being spaced apart from each other by a distance along a transverse direction of the motor vehicle seat, the distance being reduced gradually from the front end of the passenger seat portion to the rear end of the passenger seat portion, two slide units, each of which includes a slidable element received movably within a corresponding one of said left and right sliding rails, a connecting member disposed outwardly of the corresponding one of said left and right sliding rails and connected fixedly to said slidable element, and a positioning unit for retaining said slidable element at a selected one of a plurality of positions relative to the corresponding one of said left and right sliding rails, two supporting frames having upper ends, and lower ends that are connected respectively and pivotally to said connecting members of said slide units such that said upper ends of said supporting frames can pivot toward and away from each other about the pivotal connection of the lower ends, and a back supporting mechanism including a backrest mounted to said supporting frames and disposed above the passenger seat portion, and a frame-positioning device disposed between said backrest and said supporting frames to position said backrest on said supporting frames such that said slidable elements of said slide units are movable respectively and forcibly within said left and right sliding rails.