| 摘要 |
PURPOSE:To enable the quantity of a Hall element to be one and facilitate the composition and assembly, by setting a position detecting magnet rotor distinguished from a torque generating field magnet rotor. CONSTITUTION:On a rotary shaft 1, the central section of a mild steel disc is fixed, and on the back side surface of the mild steel disc, a ring-formed field magnet 5 is fitted. The field magnet 5 is composed of ring-formed ferritic magnets provided with N, S poles 5a-5d at equal pitches along the circumferential surface. The outer periphery of the field magnet rotor 5 is set to be a ring-formed position detecting magnet rotor 8, and the position detecting magnet 8 is provided with magnetic poles 8a, 8b,... and zero magnetic field sections 9a.... A Hall element 11a is contained in a part of an IC 29a, and is mounted on the intermediate section of the adjacent sections of adjacent armature coils 10a, 10c, and is confronted with the position detecting magnet rotor 8. |
