| 摘要 |
PURPOSE:To freely set F/V conversion gainly a simple constitution, by generating DC voltage corresponding to a phase difference between an output of a phase-shifting means for providing the phase-shifting quantity corresponding to frequency of an input signal, and the input signal. CONSTITUTION:A frequency signal being proportional to rotational frequency of a motor M, generated from a frequency generator 1 is applied to a phase shifter 2, and the phase is varied by the phase-shifting quantity corresponding to frequency of an input signal. Zero crossing detectors 3, 4 detect zero crossing points of input and output signals A, B of the phase shifter 2, and each output C, D are inputted to an AND gate 5. Subsequently, this gate output E is applied to an integration circuit 6, to convert to DC voltage F, then it is compared with a reference voltage E0 in level in a comparator 7, and it becomes an error signal and is used as a rotation control signal of the motor M. In this way, the F/V conversion gain is selected optionally by a filter constant. |
