| 摘要 |
PURPOSE:To automatically detect the defect of a member related to the formation of an image in early time and to warn it. CONSTITUTION:Potential sensors 51a and 52a which respectively detect the potential distribution and the density distribution of a photosensitive drum and a density sensor 53a which detects the density distribution of a transfer material which is passed through a fixing device are disposed so that all of them can be moved in the shaft direction of the photosensitive drum and connected to a decision means 60. A storage means 61 which stores the size and the arranging position of the member related to the formation of the image and a warning means 63 are connected to the decision means 60. Since the irregularity of the potential and the irregularity of the density respectively show peculiar pattern by the member related to the formation of the image such as the photosensitive drum, a developing roller, a heat roller, an exposure lamp, a destaticization lamp or a separation pawl being the generating source of such irregularity, for example, the generating source of the defect can be specified and quickly warned by detecting the pattern. |
