Tohnichi Mfg. Co., Ltd.

Shozo Aikawa

Hiroshi Tsuji

Tomohiro Ogata

Yuji Kato

Naoya Masuda

Koichi Shimura

Kyo Kan

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

Torque wrench

To make improvements in torque wrenches with a torque limiter that uses a cam mechanism and to provide a torque wrench that realizes more stable operation and is capable of highly precise tightening. In a torque wrench with a torque limiter that uses a cam mechanism, a solid columnar roller memberis engaged with a cam partof a cam shaftsuch that it is rotatably supported by a roller support lever membermounted in a head portionsuch as to be rotatable around a support shaftand such that it is pressed against the cam partby a spring force transmitting rodbiased by a torque setting spring. The roller support lever memberis configured such that the distance rfrom the support shaftto a point of application of force of the spring force transmitting rodis longer than the distance rfrom the support shaftto the roller member

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Ota-ku, Japan

Shozo Aikawa