| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce step vibration when a step-driven brushless motor stops. <P>SOLUTION: In a controller 12 of the brushless motor 10 which is step-driven for a target step for every prescribed ticking, it is discriminated whether a step deviation ΔS between a real step and the target step is not more than a prescribed difference ΔS0. When it is discriminated that the step deviation ΔS becomes not more than the prescribed difference ΔS0, a duty ratio Duty of voltage applied to exciting winding of the motor 10 is dropped to that, when the step deviation ΔS is determined to exceed the prescribed difference ΔS. Thus, conduction is performed for suppressing motor torque compared with a usual case. <P>COPYRIGHT: (C)2007,JPO&INPIT |
