Inclined surfaces are formed in areas adjacent to a tooth protruding from the inner circumferential surface of the yoke, on both sides in a motor rotation circumferential direction, and the inclined surfaces are inclined or curved toward a protruding direction of the tooth as a distance from the tooth increases in the motor rotation circumferential direction. The conductive wire includes parts extending in the motor rotation circumferential direction on both sides of the tooth in the motor rotational shaft direction in each of first to n-th turns, and bent portions bending in a thickness direction of the conductive wire are formed in the parts so as to align in a winding axis direction through the width of the conductive wire. Portions of the conductive wire on are inclined toward the protruding direction of the associated tooth as the distance from the bent portion increases in the motor rotation circumferential direction.