<p>A longitudinal support base (30) is provided with a rotating support base (10) that can slide in a longitudinal direction of the vehicle. A seat body (2) is placed on the rotating support base (10) via a rotary disc (13) so as to rotate. The longitudinal support base (30) is provided with an intermediate gear (22) that is engaged with a rack (21) extending in the longitudinal direction of the vehicle. The seat body (2) side is provided with a pinion gear (24) that is engaged with the intermediate gear (22). The rotary disc (13) is rotated by means of a driving force of an electric motor (41). Thus, when the electric motor (41) is rotated, the seat body (2) rotates and slides in the longitudinal direction. <IMAGE></p>
