CHAIR HAVING BACKREST

PROBLEM TO BE SOLVED: To simplify the structure in a chair which makes the lumbar support section of the backrest move forward so that the waist section can properly be supported even when a user shallowly sits on the seat. SOLUTION: This chair is equipped with a seat receiving base 2, an intermediate member 3, the seat 4, a back frame 5, and the backrest 6. The seat 4 is attached to the intermediate member 3 so as to retract while descending. The lower section (lumbar support section) of the backrest 6 is constituted in such a manner that a resin plate 21 of which the shape seen from the side surface can be changed is made a main member, and the lower end of the resin plate 21 is attached to the seat 4. When a person sits on the seat 4, the seat slides, and by the movement, the resin plate 21 is deformed into a forward protruding shape when received bracing action by the pressing action by the seat 4. As a result, the resin plate 21 protrudes forward. The bending deformation of the resin plate 21 is regulated by a guide body 28 which is provided on the back frame 5. COPYRIGHT: (C)2007,JPO&INPIT