To provide a chair superior in a fitness to the upper half of the body of seated person and comfortable to sit in.
A backrest 3 is provided with an inner plate 21 made of a synthetic resin and front and back cushion layers 22 and 23, and an upper part of the inner plate 21 is mounted to a back frame 12. A lumber support 15 is arranged between the backrest 3 and the back frame 12 in such a way that its height is freely adjusted. The inner plate 21 is in a plate-like form bendable and deflectable in shape in its overall surface, and a part in contact with the lumbar support 15 serves as an easily deflectable main deflection tolerant area 25. An intermediate deflection tolerant area 26 and an auxiliary deflection tolerant area 27 continue above the main deflection tolerant area 25. Since the upper part of the inner plate 21 can be bent and deflected in shape while maintaining a protruding function by the lumbar support 15, it is possible to achieve a substantially high fitting property capable of highly smoothly following the physique of a seater and posture changes.
INOUE SHINJI
Tadashi Higashino
Hiroyuki Nishi