| 摘要 |
PURPOSE:To automate the duty adjusting work for the waveforms of pulse signals and to shorten the working time for maintenance by transforming the continuous light from a light emitting part into intermittent light through an optical interrupter, receiving said light with a light receiving part, and transducing the light into an electric signal. CONSTITUTION:Light beams from light emitting parts 1a and 1b are received with light receiving parts 5a and 5b and transduced into electric signals. An optical interrupter 3 is provided at the intermediate part of the optical fibers 2a and 2b and 4a and 4b on the light emitting side and the light receiving side. The light beams from the light emitting parts 1a and 1b are transformed into the intermittent light beams. Waveform shaping parts 6a and 6b shape the transduced electric outputs from the light receiving parts 5a and 5b into ON/OFF rectangular waveform signals based on a specified reference level signal. The pulse signals having the specified duty are outputted. The pulse signals are counted in a counter 8, and the position of an elevator is detected. The duty-adjusting-command input part in a microcomputor 10 imparts a duty-adjusting command for the pulse signals. In response to this command, the high and low states of the reference level signal which is imparted to the waveform shaping parts are adjusted in the duty adjusting part so that the duty of the pulse signals from the waveform shaping parts 6a and 6b becomes the specified value. |
