ADJUSTABLE CHAIR

摘要

Disclosed herein is a chair comprising a base frame and a back frame, means for rotating said back frame relative to said base frame, said back frame including a back support to receive a trunk portion of a user, means for displacing said back support relative to said back frame, a control unit communicating with said means for rotating and said means for displacing, said control unit having adjustment means to vary the displacement of said back support according to the rotation of said back frame in order to minimize shear forces appearing between said trunk and said back support.