A new algorithm of hinge mechanism design for a folder-type mobile phone

The opening or closing stroke of a hinge mechanism for a folder-type mobile phone is divided into two portions. In the first portion, human fingers act a torque on the folder. In this portion, the rotating folder compresses a coil spring installed in the hinge mechanism. In the last portion, this compressed coil spring generates torque to rotate the folder. The design conditions for hinge mechanisms commonly adopted by most mobile phone makers are three or four point torque conditions, which specify actuating torque exerted by human fingers at three or four angular positions of folders. In this study, we have developed a new algorithm to design hinge mechanisms driven by arbitrary predetermined continuous torque in the first portion of the opening or closing stroke. Consequently, we can design hinge mechanisms satisfying various consumersʹ demands more accurately.