The innovative “variable arm clicker” mechanism allows adjusting the torque wrench by the variation of the mutual position of internal leverages, and not by loading a spring, as in the case of traditional mechanical torque wrenches. The internal spring works always in the same condition, independently of torque applied: this innovative method provides a longer life of the calibration.
In this torque wrench type, the torque wrench increases with the increase of applied force, but then, reaching the set value, it releases and does not allow to exercise additional torque for angles between 3 ° and 6 °. However, if the operator never stops applying force during this time, the torque starts to grow, easily surpassing the pre-settled torque.
There are also torque wrenches that give an angular tolerance superior to that mentioned above. In this case, the torque increases with the increase of applied force. Upon reaching the set value, the torque wrench releases and about 20° does not allow the application of additional torque.