Patent ID: 9106121
Filing Date: 2015-08-11
Classification: H02K

Abstract:
1. A double-stator motor, comprising: a housing; a shaft which is rotatably supported by the housing; a rotor which is connected to the shaft and rotates integrally with the shaft; an outer stator which is arranged radially outward of the rotor and fixed to the housing, and which has a three-phase outer-stator winding; and an inner stator which is arranged radially inward of the rotor and fixed to the housing, and which has a three-phase inner-stator winding, wherein the outer stator and the inner stator each have magnetic poles, the number of which is the same as that of the rotor, and the outer-stator winding and the inner-stator winding are connected in series in each of the phases, thereby generating winding magnetomotive force so that the magnetic poles, which are radially opposed to each other via the rotor and located at the same circumferential position, come to have the same polarity, the rotor includes: a rotor core which is configured by stacking a plurality of annular core sheets made of a soft magnetic material; a plurality of outer magnets which are embedded in a radially outward portion of the rotor core; and a plurality of inner magnets which are embedded in a radially inward portion of the rotor core, the outer magnets and the inner magnets are arranged in the rotor core in the circumferential direction, the outer magnets and the inner magnets being alternated between the radially outward portion and the radially inward portion, at a pitch equal to that of the poles of the outer stator and the inner stator so as to be magnetized so that a radially outer side thereof will serve as N poles or S poles and that a radially inner side thereof will serve as S poles or N poles, and the rotor core includes: a plurality of outer poles which are made of a soft magnetic material and are each formed between the outer magnets circumferentially adjacent to each other in the radially outward portion, and a plurality of inner poles which are made of a soft magnetic material and are each formed between the inner magnets circumferentially adjacent to each other in the radially inward portion.