To permit carrying of a seat while maintaining the seat height low by rotatably installing a main frame formed in a profile that includes a tip portion and a base portion and a sub frame between the tip portion and the base portion.

A main frame 11 and a sub frame 21 are formed in rectangular profiles and are installed on a rotation shaft 14 freely rotatable therearound. Hoist means 31 made of a chain is installed on a base portion 13 of the main frame 11. The main frame 11 and the sub frame 21 are rotated about the rotation shaft 14 to match tip portions 12 and 22, so as to insert this portion into a clearance between a seat back and a seat from the sitting side and protruding from the back side. When the tip portions 12 and 22 are rotated to be opened, the tip portions cannot be retracted from the clearance, therefore, it is possible to hoist a seat vertically. When the seat back is contacted with tilt means, seat is inhibited from moving further upward. Consequently, the standing state of the seat back is released, decreasing the total height thereby for carriage.