Trapezium-shaped permanent magnet for rotor has beveled edges at base angles of cross=section

摘要

At each of the two base angles of the cross-section of the magnet, beveled or rounded edges (5) are provided from its top surface to its bottom surface, viewed from the top. The transition between the bevel (5) or rounding and the upper surface runs parallel to the axis of symmetry of the trapezium. The cross-sectional angle between the beveled edges and the lower surface lies between 30 and 70 degrees. A rotor with permanent magnets on its external side is also claimed.