Patent ID: 7836781

Claim:
A torque-setting device comprising: a handle comprising grooves defined in an internal side thereof; a driving unit attached to an end of the handle and connected to a strain gauge; a strain spring abutted against the strain gauge within the handle; a pushing element movably but not rotationally located in the handle and abutted against the strain spring; an axle including a portion rotationally but not movably located in the handle and engaged with the pushing element so that rotation of the axle relative to the pushing element causes movement of the pushing element relative to the axle and hence the strain spring to set a value of torque; and a knob formed with a tooth and connected to another portion of the axle, wherein the knob is operable to rotate the axle relative to the pushing element, wherein the knob is movable between a first position where the tooth is inserted in one of the grooves of the handle to retain the value of torque and a second position where the tooth is removed from the grooves to allow the rotation of the knob.