Tightening torque measuring unit and torque indicating tightening device

Abstract

A tightening torque measuring unit () has an inner shaft () connectable to a first output shaft () of a tightening device main body () and an outer shaft () connectable to a second output shaft () of the body. The inner shaft () is provided with a tightening socket (), and the outer shaft () with a reaction force receiver (). The outer shaft () has strain gauges (), and an indicator () for converting an amount of strain detected by the gauges into a corresponding tightening torque value. Since the reaction force receiver () can be attached to the measuring unit (), the tightening reaction force is prevented from acting to knock down the receiver (), enabling the unit () to measure tightening torque, with the device main body (), the measuring unit () and the socket () positioned in alignment with the axis of the nut to be tightened.