| 摘要 |
PURPOSE:To set a proper copying time suitable for transfer paper size with simple constitution by detecting the start and end points of transfer from a transfer side signal and detection signals from a scanning sensor and a home sensor, and controlling the variation of the rotating speed of a rotary drum. CONSTITUTION:Copying operation is started, the exposure scanning of a scanning optical system 23 is started with the detection signal from the scanning sensor 37, and an electrostatic latent image is formed. Development is started at development start timing and the image is developed with complementary color toner. Transfer from a transfer drum 27 to transfer paper is started at t2 seconds after the scanning start period. This time t2 corresponds to the reference position of the drum 27 which is detected by the home sensor 23 and the front end of the transfer paper 26 is at a position corresponding to the front end of the image. On the other hand, t1 seconds are elapsed after the start period of the scanning, original scanning is finished and an optical system 23 begins to return and finishes the returning operation t2 seconds later. |
