Patent ID: 6459185
Filing Date: 2002-10-01
Classification: H02K

Abstract:
An electric machine comprising the following features:(a) an outer, first stator part and an inner, second stator part, the two stator parts being coaxial and being radially spaced apart by an intermediate space; (b) each stator part has, facing the intermediate space, a circumferential series of stator poles, at least a partial number of which carries a winding; (c) a rotor part disposed in the intermediate space; (d) the rotor part has a circumferential series of alternating permanent magnets and magnetic flux conducting pieces, said permanent magnets being magnetized in circumferential direction; (e) the width of the permanent magnetsâ€”measured in circumferential directionâ€”is larger on the central radius of the rotor part than radially outside and radially inside on the rotor part and the width of the magnetic flux conducting piecesâ€”measured in circumferential direction is correspondingly smaller on the central radius of the rotor part than radially outside and radially inside on the rotor part; (f) a first circumferential series of magnetic circuits whichâ€”as seen in a plane perpendicular to the rotor axisâ€”each extend through two adjacent stator poles of the first stator part in the plane considered and through two adjacent magnetic flux conducting pieces of the rotor part in the plane considered and through the permanent magnet between the two adjacent magnetic flux conducting pieces in the plane considered, and a second circumferential series of magnetic circuits whichâ€”as seen in a plane perpendicular to the rotor axisâ€”extend through two adjacent stator poles of the second stator part in the plane considered and through two adjacent magnetic flux conducting pieces of the rotor part in the plane considered as well as through the permanent magnet between the two adjacent magnetic flux conducting pieces in the plane considered, characterized in (g) that the magnetic flux conducting pieces and/or the permanent magnets, in the direction of the rotor axis, are subdivided into a plurality of electrically isolated sections.