Patent ID: 6856108

Claim:
A switched reluctance motor comprising: a stator having n poles radially inwardly extending from an inner surface of said stator, a field coil wound about each pole of said n poles; a rotor positioned inside said stator, and configured to rotate by a reluctance torque generated between said stator and said rotor; a ring magnet positioned around said rotor such that n N-poles and n S-poles of the ring magnet are positioned around said rotor in a ring configuration; a parking magnet arranged to face said ring magnet, and configured to stop said rotor at a normal torque generating region by an attractive force between said parking magnet and said ring magnet; a sensor facing said ring magnet at a side of said ring magnet opposite said parking magnet, said sensor configured to detect information about a position and speed of said rotor; and a driving control unit configured to apply a driving pulse to said stator, based on the information about the position and speed of the rotor detected by said sensor, wherein said sensor comprises; a first sensor facing said ring magnet at a side of said ring magnet opposite said parking magnet; and a second sensor spaced from the first sensor at a predetermined angle, said first and second sensors of said sensor are configured to generate respective first and second pulse signals in accordance with a periodic variation in polarity of said ring magnet sensed by said sensor, and the first and second pulse signals are configured to be generated with a time difference corresponding to the angle between said first and second sensors, and wherein said driving control unit is further configured to apply an aligning pulse to said stator when the position of said rotor sensed by said sensor corresponds to a reverse torque-generating region.