Torque wrench

Abstract

A torque wrench equipped with a cam-type torque detection mechanism is provided which is capable of detecting a torque with high accuracy, providing a non-unusual-feeling of handle operation after torque has been detected, and enabling tightening of fastened members such as bolts with safety. In a torque wrench equipped with the cam-type torque detection mechanism, a cam portionformed on the outer circumference of a tubular camincludes: a static engagement cam surfacewith which a roller memberin a static status engages in a non-operated status; a gradually increasing torque peak cam surfacewhich is connected to the static engagement cam surfaceand with which the roller memberis brought into contact while moving to thereby gradually increase the torque peak value; a cam top surfaceforming the cam top portion continued to the gradually increasing torque peak cam surface; a gradually decreasing torque cam surfacefor gradually decreasing a plus torque to the roller memberto zero; and a minus torque cam surfacefor imparting a minus torque to the roller memberhaving passed over the gradually decreasing torque cam surface