| 摘要 |
PURPOSE:To reduce a cogging torque by specifying the disposition of a groove for windings more than the number of poles of a field. CONSTITUTION:A magnet 3 mounted on a rotor 2 has field poles of P poles (P is even number), and an armature core 4 has teeth formed between grooves (a)- (x) for 6P pieces of windings wound with windings of 3 phases. The core 4 has L pieces (L is integer number) of long teeth at the effective pitch larger than D=60 deg./P, and M pieces (M is integer number) of short teeth at the effective pitch smaller than D, and the numbers of the long and short teeth are set to L>=3, M>=3. Short tooth blocks of two or more short teeth and long tooth blocks of at least one long tooth are the same number, the short and long tooth blocks are alternately disposed on the circumference, and the numbers of the long and short blocks are integer number magnification of 3. |
