PERMANENT MAGNET STRUCTURE FOR USE IN ELECTRIC MACHINERY

Magnetic circuit losses due to unnecessary magnetic fields are greatly curtailed or eliminated relative to the permanent magnet structures of electric machinery, without employing a conventional shunt or pole pieces. At least one coaxial cylinder of magnetic material is included in each permanent magnet structure of the invention and is magnetized to provide individual magnetic fields between sets of north and south poles on only one cylindrical surface thereof. Each of the cylinders is constructed from a plurality of segments in one preferred embodiment thereof and magnetically rigid materials are utilized to enhance the field magnitudes in another preferred thereof. Segments having a substantially triangular cross sectional configuration are utilized in other preferred embodiments, while flux contributions from at least three segments combine to sustain each set of north and south poles in still other preferred embodiments.