| 摘要 |
PURPOSE:To reduce unnecessary toner consumption and the load on a cleaning mechanism by increasing the quantity of light from a static charge erasing lamp tenporarily when the rear end of transfer paper and the front of a picture formation area formed in the next copying cycle are detected. CONSTITUTION:When the rear end of the transfer paper reaches a light emitting diode 17 as the static charge erasing lamp, trigger signals S1 and S2 are outputted by trigger signal generating circuits 18 and 19. Therefore, transistors TR1 and TR2 turn on simultaneously in a time internal corresponding to the pulse width of the signal S2, and the light from the light emitting diode 17 where a large current flows increase temporarily. Therefore, the light energy by the diode 17 becomes large enough for charge erasure and almost all unnecessary charges are erased. Similarly, the light energy by the light emitting diode 17 becomes large enough right before the front end of the picture formation area formed in the next copying cycle reaches the static charge erasing lamp, so unnecessary charges remaining at the front end of the picture forming area are erased. |
