Patent ID: 8624446

Claim:
An electric machine, comprising: a first stator; a plurality of movers arranged at positions spaced apart from each other such that an electric phase difference between two adjacent movers is 60° or 180°, the plurality of movers linearly or curvedly moving or rotating with respect to the first stator; and a second stator having the same structure as the first stator, wherein the plurality of movers are provided between the first stator and the second stator, wherein each of the plurality of movers comprises: mover teeth in multiples of three, the mover teeth being spaced apart from each other at regular intervals; and a plurality of phase coils wound around each of the mover teeth, each of the plurality of phase coils of a first mover of the plurality of movers having a corresponding phase coil of a second mover with an electrical phase difference of 180° with respect to the respective phase coil of the first mover, wherein the plurality of phase coils include three-phase coils configured in the form of an air core, or phase coils configured in the form of an air core such that three-phase coils are repeated in a direction in which the plurality of movers move, and wherein the first and second stators each include an iron core having a plurality of salient poles, with permanent magnets provided in depressions defined between the salient poles, and wherein the salient poles of the first and second stators and the corresponding mover teeth of the plurality of movers are skewed at predetermined angles and face each other.