Unidirectional brushless motor

摘要

An inexpensive brushless motor including a single position detecting element can start itself and can rotate smoothly with good efficiency and reduced noise. The motor comprises a stator core having T-shaped radial stator poles with driving coils wound on all or some of the stator poles. A field magnet having driving alternate N and S magnetic pole zones is mounted for rotation in an opposing relationship to circumferential faces of the stator poles of the stator core. A cogging generating magnetic plate is located in an opposing relationship below the field magnet and has a cutaway portion formed therein which has a suitable angular width such that the magnetic plate may generate a cogging, to move the field magnet by attraction therebetween to a position other than any dead point, and from which the field magnet can start itself. The single position-detecting element is located such that it may detect no dead point upon starting of the motor.