| 摘要 |
PURPOSE:To keep a motor at predetermined speed on the basis of reference speed signals by varying the time of duration of the output signals of a circuit outputting signals while responding to rotation signals in response to the reference speed signals. CONSTITUTION:A phase comparator 1 compares the phase of a reference speed signal R1 and the phase of the rotation signal corresponding to the speed of revolution of a motor 2 from an encoder 3, and the output is inputted to an addition circuit 5. Output from the encoder 3 is also inputted to an F/V converter 4, and the output is inputted to an addition circuit 5. The time of duration of the output signals of the F/V converter 4 is varied in response to the reference speed signals R1 because the F/V converter 4 has a timer circuit 4a. The output of the addition circuit 5 is inputted to a pulse-width modulation circuit 8 through a filter 6, and compared with a triangular wave from a triangular-wave oscillator 7, and the output is supplied to the motor 2. |
