IMAGE QUALITY STABILIZING DEVICE FOR ELECTROPHOTOGRAPHIC DEVICE

摘要

PURPOSE:To control the rotational speed of a stirring roller according to the change of transferring efficiency caused by the deterioration of toner or the change of an environment and to stabilize the quality of a formed image. CONSTITUTION:An optical sensor 9 which optically detects the density of a toner patch formed on a photosensitive drum is provided. Then, the quality of the formed image is stabilized by controlling the respective parts of a copying process so that the detected value becomes a reference value which is previously set. Besides, a process control part 13 being a roller rotation control means which controls the rotational speed of the stirring roller 4a provided in a developing device so that the value detected by the sensor 9 of the density of residual toner on the photosensitive drum after the reformed toner patch is transferred on a transfer paper becomes a residual quantity reference value which is previously set after the respective parts of the copying process are controlled based on the detection of the density of the toner patch is provided.