TORQUE SENSOR AND TORQUE SENSING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a torque sensor simplifying its manufacture by dispensing with permanently magnetizing a shaft or a collar mounted on the shaft, and resultantly dispensing with a manufacturing process for permanently magnetizing the collar or the shaft. SOLUTION: This torque sensor 8 is equipped with the shaft 16 made of a magnetostrictive material and a pair of magnets 10 and 12. The pair of magnets 10 and 12 are disposed around the shaft 16 so as to induce a local magnetic field in the shaft 16 between magnetic poles 11 and 13 having polarities opposite to each other. Torque 38 exerted on the shaft is detected by a magnetic flux detector 18 disposed between the poles 11 and 13 and around the shaft 16 so as to detect a component of the magnetic field leaking from the shaft.