TORQUE DETECTION DEVICE

摘要

The number n of N-poles (40) and S-poles (41) circumferentially aligned on the cylindrical magnet (4) that integrally rotates with the first shaft (1) is determined so as to be a greatest integer that satisfies the following formula that includes a maximum value T max (Nm) of the torque to be detected and a torsion spring constant k (Nm/deg) of the torsion bar (3) connecting the first shaft (1) and the second shaft (2): 2 ‹ n ‹ T max / k < 360
The cylindrical magnet (4) includes teeth-shaped portions (42) in which portions corresponding to the N-poles (40) and the S-poles (41) are of a protruding shape, so that adhesion of magnetic dust concentrates at the protruding portions. Thus, a torque detecting apparatus is provided that reduces the effect of the adhesion of the magnetic dust, so as to attain higher detection sensitivity and thereby improve the detection accuracy, without incurring an increase in cost.