BRUSHLESS MOTOR AND METHOD FOR MANUFACTURING ROTOR USED FOR THE SAME

摘要

PROBLEM TO BE SOLVED: To improve demagnetization resistance while suppressing reduction in an induced voltage in a magnetic flux concentration type brushless motor which executes weak magnetic field control.SOLUTION: When a distance between an end surface 14b on a stator 20 side of a magnetic material 14 in the radial direction of a rotor 10 and the end surface 16a on the stator 20 side of a magnet 16 is Lr, and a central angle sandwiched by two radius lines connecting respective both ends on the side in peripheral direction in a rotor side wide part 14a and a rotary shaft A, which is viewed from the direction of the rotary shaft A of the rotor 10, is τr, Lr and τr are set so as to be 2.0 mm≤Lr≤3.5 mm and 110°≤τr≤140°.