NONUNIFORM CONTACTLESS DC MOTOR Russian patent published in 1998 - IPC

FIELD: electric drives. SUBSTANCE: motor has stator windings 1 and 2 each placed in its respective layer, rotor permanent magnet 3, Hall-effect rotor position detector 4, stator permanent magnets 5 setting rotor in definite position. Opposing torque due to permanent magnets 5, especially during breakaway moment, can be reduced by arranging them on any end of rotor permanent magnet or even beyond it. Windings 1 and 2 may be of wave type. With such stator design, motor shaft torque is built up due to sequential action of windings 1 and 2 and finally due to stator permanent magnets 5. EFFECT: simplified motor commutation scheme due to positioning rotor so that magnetic field set up by its permanent magnet acts on first rotor position detector, depending on motor sense of rotation, within as short time as possible. 2 dwg