PROBLEM TO BE SOLVED: To provide a chair with which a person can sit down for a long time without getting tired, raises the pelvis effortlessly and comfortably only by sitting, lets the lumbar spine, the thoracic vertebra, the cervical spine and the head into a line from the pelvis so that he/she can have deep abdominal respiration and get relaxed.SOLUTION: An accurate arc is made on a seating face in a lateral direction, a gentle convex surface is made on the whole seating face in an anteroposterior direction and a gentle projection is made at a position just in front of the ischium on the seating face, a backrest has a projection at a position 1 cm below the height of the iliac crest in the upper coxal bone and the backrest has a space avoiding contact with the spine. The positional relation between the front end of the backrest and the peak of the rear seating face is determined by the pelvis position and the size of lumbar curvature and the part touching the iliac crest of the backrest is formed with a projection. The last fine adjustment is made by using a seating comfortableness test tool based on the data measured in advance.COPYRIGHT: (C)2016,JPO&INPIT【課題】長時間座っていても疲れることなく、座るだけで骨盤を無理なく・気持ちよく起こし、骨盤から腰椎・胸椎・頚椎・頭を一直線に通すことで、深い複式呼吸ができて、リラックスできる椅子を提供する。【解決手段】座面の横方向に正確な円弧と、座面前後方向全域にわたり、緩やかな凸曲面と、座骨直前にあたる位置の座面にゆるい突起を設け、背もたれは、寛骨上部の腸骨稜の高さより、1cm下がったところに突起を設け、背もたれには背骨に当たらない間隔を設ける。背もたれ前端と、座面後方のピークの位置関係は、骨盤位置・腰部湾曲の寸法により決まり、背もたれの腸骨稜と接する部分に突起を設ける。事前に測定したデータを基に座り心地試験具を用いて最終的な微調整を行なう。【選択図】図14
