Patent ID: 7550894

Claim:
A rotary electrical machine comprising: a rotor rotational about an axis of a rotating shaft in a first rotational direction; and a stator disposed so as to oppose to the rotor, wherein one of the rotor and the stator is divided into at least two portions in the axial direction, a first portion of the at least two portions being movable at least in a rotational direction or a reverse rotational direction of the first rotational direction relative to a second of the at least two portions in such a manner that a gap between the first portion and the second portion forms a magnetic resistance that is variable, the first portion being a first stator core having a first set of teeth, each tooth of the first set of teeth having an end surface opposite the rotor and a second end surface facing away from the end surface, each tooth of the first set of teeth having a winding wound around a circumferential side surface thereof, and the second portion being a second stator core having a second set of teeth, the second set of teeth having end portions facing the second end surfaces of the first set of teeth.