| 摘要 |
PURPOSE:To obtain a superior rotation controller by providing a means which applies disturbance to a rotation control system so that the constant mechanical position of a rotating medium coincides with the time position of a reference signal. CONSTITUTION:Phases of a tone wheel pulse (TWP) shaped by a gate 20 and a video disk (VD) signal is compared with each other by a phase detecting circuit 21 and an outgoing disturbance generating circuit 22 gets ready to operate when a rotating speed enters a specific range. At this time, a gate-in detecting circuit 24 detects the time position of the TWP to the VD signal. The circuit 2 generates a kick pulse as a disturbance until the time position becomes a specific position, and the pulse generation is stopped at the specific position, so that the control system performs normal phase control. The circuit 22 judges in which of positive and negative directions the disturbance is generated on the basis of the outputs of the circuits 21 and 24 and whether the cycle of the kick pulse is long or not according to the distance of the time position of the TWP and VD signal. Consequently, the superior rotation controller is obtained. |
