| 摘要 |
PROBLEM TO BE SOLVED: To improve detection precision of a rotation position of a rotor. SOLUTION: In a brushless motor, detection units 16U, 16V, 16W are provided in opposition to teeth 24U2, 24V2, 24W2 in the respective phases, and disposed at positions where polarities are switched according to changes in the direction of leakage magnetic flux from a rotor magnet 26 when windings 22U2, 22V2, 22W2 are brought into a non-conductive state. Moreover, a control unit 18 switches the conductive states of a plurality of windings 22U1 to 22W2 based on output signals from the detection units 16U, 16V, 16W so that the windings 22U2, 22V2, 22W2 are brought into the non-conductive state when the polarities of the detection units 16U, 16V, 16W are switched. According to this configuration, the effect of magnetic flux from a stator 12 to the output signals of the detection units 16U, 16V, 16W can be reduced, thereby improving the detection precision of the rotation position of the rotor 14. COPYRIGHT: (C)2010,JPO&INPIT |
