Patent ID: 8134270
Filing Date: 2012-03-13
Classification: H02K

Abstract:
1. A synchronous motor driven by a two-phase alternating current composed of a first-phase alternating current and a second-phase alternating current which have a phase difference with respect to each other, the synchronous motor comprising: a rotor that includes a plurality of magnetic poles arranged at equal intervals in a circumferential direction; and a stator that includes an annular yoke and N teeth arranged at intervals on the yoke in the circumferential direction, N being an integer of four or greater, wherein the stator is configured such that the N teeth (i) include sets of n teeth, n teeth in each set being disposed at a same position in terms of electrical angle, and (ii) are grouped into first groups of k teeth, k teeth in each first group being aligned in the circumferential direction, each first group being rotationally symmetric about an axis of the yoke, n and k each being an integer of two or greater, and N=k·n, one of the k teeth in each first group is a reference tooth, and at least another one of the k teeth in the first group is a displaced tooth which is displaced from a position corresponding to an integral multiple of the phase difference with respect to the reference tooth in electrical angle, only either one of first-type coils or one of second-type coils is wound on the reference tooth by concentrated winding, the first-type coils being supplied with the first-phase alternating current, and the second-type coils being supplied with the second-phase alternating current, both one of the first-type coils and one of the second-type coils are each wound on the displaced tooth by concentrated winding, first-type coils wound on the teeth in each first group are connected in series, and second-type coils wound on k teeth, aligned in the circumferential direction, in each of second groups are connected in series, the second groups being either same or different with respect to the first groups.