| 摘要 |
PURPOSE:To conduct a control in the vicinity of a resonance frequency safely and correctly by making the rate of change of a drive frequency larger in the region of high drive frequency and smaller in the region of low drive frequency. CONSTITUTION:The present rotational speed computed by a signal input from a pulse encoder 8 connected with a rotor 6r is compared with a target rotational speed. When the present rotational speed is lower than said target rotational speed, a control is conducted so as to increase said existing rotational speed. On the other hand, when the present rotational speed is higher than the target rotational speed, the control is conducted so as to reduce the existing rotational speed. Further, when a driving residue is large, a controller 1 also adopts a large value as the target rotational speed so as to conduct a control to lower a frequency to be applied to a vibrating motor 6 thereby making the rotational speed higher. |
