Vehicle seat back assembly

摘要

A vehicle seat back assembly is provided with: a seat back frame (2) having an upper frame component (2a) and a lower frame component (2c); a movable support member (7) supported with the upper frame component for tilting movement in forward and rearward directions relative to the seat back frame and vertical movement relative to the seat back frame; an actuation member (4) supported with a lower section of the movable support member and moveable rearward in response to impact force exerted by a seat occupant relatively to the seat back frame; a first support member (5) coupled to the lower frame component of the seat back frame; a second support member (6) coupled to the movable support member; a head rest (3) supported with an upper section of the movable support member; and a lumbar support member (8) having an upper end portion coupled to the second support member and a lower end portion coupled to the first support member to take on a position to resiliently support a lumbar of the seat occupant. The first support member and the second support member support the upper end portion and the lower end portion of the lumbar support member to allow the upper end portion and the lower end portion of the lumbar support member to be tilted in forward and rearward directions relatively to the seat back frame and vertically moved relatively to the seat back frame. <IMAGE>