| 摘要 |
PROBLEM TO BE SOLVED: To prevent a faulty image from being formed caused by defective electrification occurring in accordance with the soil of a contact type electrifying member being over an allowable range and to prevent a serious problem from occurring caused by the attachment of carrier by detecting difference between the electrifying potential of a body to be electrified and voltage applied to the electrifying member and forming an image other than image information at an image part according to the detection signal thereof. SOLUTION: The electrifying member 2 to which the voltage is applied is brought into contact with the body to be electrified 1 so as to electrify the body 1. Then, the difference between the electrifying potential of the body 1 and the voltage applied to the electrifying member 2 is detected. According to the detection signal, the image other than the image information is formed at at least the image part. That means, the image other than the image information is intentionally formed by changing the condition of bias applied to the contact type electrifying member 2 so that the potential of the body 1 becomes a desired value in accordance with the deterioration of the electrifying member 2 and regarding that the deterioration of the electrifying member 2 becomes over the allowable range when the value which should be changed is over some value. Thus, the faulty image is formed so as to press maintenance. |
