| 摘要 |
PURPOSE:To simplify the structure of a motor by processing signals form two magnetoelectric transducers for detecting the rotary position of a motor via three differential amplifiers, and driving a motor coil, thereby reducing the number of the transducers. CONSTITUTION:Two Hall elements 11, 13 for detecting the rotor position are provided at 120 deg. interval at a brushless motor which has a rotor made of a permanent magnet 10 and a stator made of coils L11-L13. The output signals are applied to differential amplifiers 20, 22, the reverse phase output of the amplifier 10 and the output of the amplifier 22 are applied to the third differential amplifier 21, the outputs of which are inputted to an arithmetic circuit 23, which calculates to drive stator coils L11-L13. Accordingly, two Hall elements are provided, even if the number is less than the conventional one, the rotaty position can be accurately detected, and the number of terminals of the Hall elements and integrated circuits IC can be deleted. |
