MAGNET TYPE BRUSHLESS MOTOR

摘要

PROBLEM TO BE SOLVED: To provide a magnet type brushless motor producing a high torque during low speed rotation while keeping a high conversion efficiency up to an r.p.m. about three times as high as conventional r.p.m. SOLUTION: The field magnet 3 of a rotor 2 comprises first and second field magnets 31, 32 rotatable relatively. A mechanism for varying the phase of combined pole of the field magnet relative to the first field magnet 31 as the rotor 2 rotates arranges the poles of different polarity in the first and second field magnets 31, 32 during low speed rotation. A governor functions with centrifugal force as the rotational speed increases and a relative rotational force is imparted to the second field magnet 32.