| 摘要 |
PURPOSE:To detect the thickness of transfer paper of various thickness, by providing a transfer paper overlapping delivery detecting section in a transfer paper path before copying, making reference set of thickness with the 1st paper and detecting overlapping delivery from the 2nd sheet. CONSTITUTION:A transfer paper passes through between a light emitting element 1 and a photodetector 2. At the transfer paper for the 1st, no overlapped delivery is detected and a reference signal is given from a reference set circuit 6 to an overlapping delivery discriminating circuit 8 when the 2nd copy operation started, and an output from the photodetector 2 is given to the detection section via an AD converter 5. The said circuit 8 compares an output from the photodetector 2 with the reference value and given the result to a control circuit 3. At the discrimination as no overlapping delivery, the reference value of the circuit 6 is corrected based on an output of a photodetector, and if discriminated as overlapping delivery, the reference value of a reference value set circuit 6 is not corrected. |
