| 摘要 |
PURPOSE:To reduce an error by obtaining the average value of a pulse period of a plurality of detection pulses, and generating a feedback signal on the basis of the means value. CONSTITUTION:A period measuring circuit 14 obtains a period of a detection pulse fed from an optical sensor 12. A period memory 15 stores the periods of a plurality of detection pulses measured by a period measuring circuit 15. An average value calculator 16 obtains the average value of the periods on the basis of the output from the memory 15, and applies it to a servo feedback generator 17. A servo circuit 18 compares the outputs of the generator 17 and a speed setter 19 to control a space motor 1. Thus, an error of the detection pulse with respect to the set value can be averaged. |
