BACKREST STRUCTURE OF SEAT BACK

摘要

PROBLEM TO BE SOLVED: To increase a feeling of being supported by a support member and a feeling of stroke and firmly support the lumbar and the pelvis of the seater by supporting the waist of the seater in a manner corresponding to the posture of the seater, even if the seater is seated in a forwardly off position. SOLUTION: A first support member 21 formed in an approximately U-shape at each side frame 16 is rotatably supported at its right and left upper ends 21a. The lower part of each side frame 16 is connected with the lower part of the first support member 21 by means of springs 25 and 26. The mid part of a side 33a of a second support member 31 is rotatably attached to the vertical mid part of a side 21b of the first support member 21. The upper part of each side frame 16 is connected with the second support member 31 by means of a spring 47.