MOTOR CONTROLLER

PURPOSE:To secure the synchronization with the revolutions of a motor for the synchronizing signals having the comparatively wide range of frequencies, by deciding a standard speed of revolution of the motor by applying an integer multiple or one-to-an-integer multiple to a synchronizing signal supplied from outside or a synchronizing signal produced inside. CONSTITUTION:An external composite synchronizing signal (b) is separated into the horizontal and vertical synchronizing signals (c) and (d) by a synchronizing signal separating circuit 11. The signal (c) is supplied to a frequency multiplying circuit 17. The circuit 17 multiplies the frequency of the signal (c) by N and delivers it to a counter circuit 5. The frequency of the output signal of a revolving speed detecting circuit 7 is defined as f=R.Z, where the frequency of the signal (c) is referred to as fHD, the number of revolutions of a motor 10 is R at every second and the proportion constant is Z respectively. Thus a signal having a frequency f=R.Z and a signal having a frequency f=N.fHD are delivered to the circuit 5. A speed error detecting circuit 56 consists of the circuit 5 and a frequency difference detecting circuit 6.