| 摘要 |
PURPOSE:To improve the reproducibility of position by storing the information being the correspondence between a phase difference actually counted and the absolute angle of a reference origin detection slit in a memory in advance and applying the home position return based on the information. CONSTITUTION:When an LED 7 projects light between slits 31,32 at application of power for a robot or the like, a motor 4 is driven clockwise (direction A) and stops by a detection signal from a home position detecting circuit 10 when a home position signal detector 9 detects the slit 32. A phase counter circuit 14 obtains the phase difference between an inputted waveform signal fS and a reference waveform signal fR and gives the resulting signal to a microprocessor 15. The reference waveform signal fR is a waveform signal obtained in closing any of switches 111, 112 m-. The microprocessor 15 finds out an absolute angle from a table in a memory 151 based on the phase difference signal from the phase counter circuit 14. This is the turning position of a code disk 1 at the present point of time and then the home position returning is finished.
|
