MEASURING APPARATUS FOR FRICTION FORCE

PROBLEM TO BE SOLVED: To set a winding angle in a wide range and measure a friction force under the same condition even when the winding angle is changed, by making a detector-mounting jig having a load detector fixed thereto rotatable about the same rotating center as a pulley. SOLUTION: A shaft 7 is penetrated through a pulley 1 and a detector- mounting jig 4 arranged in parallel to each other. The pulley 1 rotates together with the shaft 7, and the detector-mounting jig 4 freely rotates relatively to the shaft 7. A winding angle is changed by rotating the jig 4 about the same rotating center as that of the pulley 1. Therefore, a length L of a belt 2 from a winding start end of the pulley 1 to a load detector 3 is never changed. Even when the winding angle is changed in a range from 0 deg. to over 180 deg., a friction force can be measured under the same condition. In the case of a carrier belt or the like, while an actual winding angle is always changed due to the vibration of the carrier belt or the like, if a brake 5 is turned loose and the mounting jig 4 is set in the rotatable fashion and rotated during the measurement, the friction force when the winding angle is changed can be measured as well.