When rotating with fixed end- side axis parts (43, 53) set as rotational axis fulcrums, rotating end- side axis parts (45, 55) of a forward link (41) and a rear link ( 1) move in an u -down direction. The range of rotation of the forward link (41) i s arranged in a manner such that the rotating end- side axis part (45) of the forward link (41) i s always above a rotation center join ing line (L). The range of rotation of the rear link ( 1) i s arranged in a manner such that the rotating end- side axis part (55) of the rear link ( 1) i s in a range that straddles the rotation center joining line (L). A s a result, the rotating end- side axis part (45) of the forward link (41) i s lowered, and only the rotating end-side axis part (55) of the rear link (51) i s raised, until the point where a ro tating end joining line (M) switches :from a below- side position to an above- side position relative to the fixed end-side axis part (53) of the rear link ( 1). Hence, it i s possible to effectively lift a seat cushion upward when a passenger gets in or out of a vehi cle, in a manner such that the position of the ni s of the passenger are higher relative to the position of the knees of the passenger.
