| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a permanent magnet and a magnetism detecting element for special use for positonal detection. SOLUTION: A permanent magnet 14 is magnetized in eight magnetic poles and a boundary 14a-14h between each two adjacent magnetic poles is slanted. The angle θ of one 14a of the boundaries is made different from the angle θ' of the other boundaries 14b-14h. In this case, the angle θ of the boundary 14a is set larger than the angle θ' of the other boundaries 14b-14h. By forming one of the boundaries between the magnetic poles of a field magnet section different from the angles of the other boundaries and installing a position detection signal generating means 15 which detects the voltages appearing at both ends of two coils of a stator winding in one phase and then generates a position detecting signal, a permanent magnet and a magnetism element, both of which are for special use for positional detection, are not necessary and thereby the cost can be reduced. |
