Rotating electric machine with bevelled armature poles

摘要

A rotating electric machine comprises an armature arrange opposite the periphery of a magnet which is rigidly fitted to a rotary shaft. The armature has a plurality of salient poles arranged on it and projecting towards the magnet. The machine is characterized in that the surface of each of the salient poles facing the magnet comprises bevelled areas arranged at the lateral ends thereof and the magnet is a hollow cylindrical ring magnet. With such an arrangement, its induced voltage can show a sustained sinusoidal waveform which is free from high harmonics to an extent greater or equal to that of a rotating electric machine comprising a segmented magnet and consequently the level of cogging of the inventive machine can be minimized. If the ring magnet of a rotating electric machine according to the invention is skewedly magnetized relative to the axis of the ring magnet, the effect of the machine in maintaining the sinusoidal waveform of the induced voltage can be further enhanced.