Abstract
In order to confirm the reliability of bolted joints, it is important to precisely grasp the tightening torque and bolt axial force. But, how to tighten a small screw by safe torque have not yet been proposed We developed a low torque measurement device by means of magnet and cam mechanism. The various magnitude of torque was produced by changing the adsorption power of the magnet and by exchanging 4 kinds of cams. Thus, the output torque is obtained in the range from 0.100 N*m to 1.167 N*m, and the proposed plus screwdriver enables to tighten precisely the small screw from diameter 4.5mm to diameter 1mm.
