Patent ID: 8248019

Claim:
A brushless motor, which has a rotor provided with a magnetic pole, polyphase motor windings for rotating the rotor, and current supply means for supplying a drive current to the polyphase motor windings, wherein any one of the polyphase motor windings is specified as a first winding and the rest of the plurality of motor windings as second windings, and wherein the brushless motor comprises: rotating means for rotating the rotor by simultaneously applying the drive current between two of the second windings where phases and amplitudes of voltage drop caused by inductances of the second windings become equal, and the first winding; voltage difference acquisition means for acquiring a difference in voltage acting on the two second windings to which the drive current is applied; magnetic pole position acquisition means for acquiring a magnetic pole position of the rotor based on the difference in voltage acquired by the voltage difference acquisition means; and first drive current control means for controlling the drive current based on the magnetic pole position of the rotor that is acquired by the magnetic pole position acquisition means.