PERMENENT MAGNET ROTATING MACHINE

摘要

In a rotating machine comprising a rotor including a rotor core and a plurality of permanent magnet segments, and a stator including a stator core and windings, the permanent magnet segment is obtained by disposing a powder comprising an R² oxide, R³ fluoride or R⁴ oxyfluoride on a sintered magnet body of R¹-Fe-B composition, wherein R¹ to R⁴ are rare earth elements, and heat treating the powder-covered magnet body. The permanent magnet segment of a cross-sectional shape which is tapered from the center toward opposed ends has a higher coercive force at the ends than at the center.