| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily control a capstan motor so that power consumptions of a motor drive circuit and the motor do not exceed a maximum supply power even when a rotational speed of the motor is changed. SOLUTION: A driver of the capstan motor comprises a calculating means for calculating a limit voltage Vlim of a drive voltage using a linear expression in response to a rotational speed Rx when a rotational speed of the motor is changed from a primary formula, a drive voltage setting means for setting a drive voltage Vn in response to the speed Rx when the speed is changed, a comparing means for comparing the voltage Vlim with the voltage Vn in amplitude when the speed is changed, and a change means for changing a drive voltage Vs in response to the speed Rx when the speed is changed to Vs=lim when a compared result of the comparing means is Vn>Vlim. In this case, when the compared result of the comparing means is Vn<=Vlim, the drive voltage Vs in response to the speed Rx when the speed is changed remains Vs=Vn as it is.</p> |
