Brushless DC motor having low torque ripple

摘要

The electric motor has a first assembly including a series of permanent magnets (M1,M2) of opposite perpendicular polarisation. Facing the magnets is a ferromagnetic polar piece (P1), forming a magnetic gap (E). A second assembly rotatably movable w.r.t. the first assembly, includes winding (B) that is placed in the gap and is rotatable. A switching mechanism (D) is connected to the windings. The polar piece has wider edge gap zones, thus retaining the magnetic field.