| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a brushless fan motor capable of detecting a stopping position of a rotor with high precision. <P>SOLUTION: When detecting a rotor stopping position of a brushless fan motor used in a rotating mechanism of a radiator fan disposed at a radiator, position signal generation means generates signals for commanding energization patterns of electric currents running through coils of a plurality of phases. Current comparison means outputs a detection signal when a current value of an electric current running through the coil is equal to or higher than a predetermined threshold value. A counter counts the time from an output of a signal for commanding an energization pattern to an output of a detection signal for each energization pattern. Position estimation means determines a rotor stopping position from the magnitude of a count value counted for each energization pattern. <P>COPYRIGHT: (C)2013,JPO&INPIT |
