| 摘要 |
PURPOSE:To ensure that the luminous amount of a print pattern can be inspected accurately, if the transfer speed of sheets changes by providing a reference level setting part which sets a reference level of the luminous amount in accordance with the transfer speed of sheets and a comparison part which compares a reference level established by the setting part with an output signal from a flight receiving part. CONSTITUTION:A rotary encoder 5 detects a speed at which sheets 1 are transferred and outputs a frequency signal in compliance with the transfer speed. A reference level setting part 6 converts an output from the rotary encoder 5 to a voltage signal equal to the output frequency. In addition, a comparison part 7 compares an output from a photoelectric conversion part 4 with an output from a reference level setting part 6. Then the comparison part 7 connects 'passed' signal, if the level of an output signal from the photoelectric conversion part 4 is higher than the reference level, and connects 'failed' signal, if said output signal is lower than the reference level. Thus it is possible to inspect the luminous amount of a constantly correct pattern, if the transfer speed is not constant. |
