| 摘要 |
PURPOSE:To always execute a replacement of a discharge wire or its cleaning at a correct time by detecting a current or a voltage of the discharge wire and outputting a driving signal when a detected value reaches a picture quality drop allowable limit reference value set in advance. CONSTITUTION:A picture quality level is decided by detecting a current or voltage value of a discharge wire or a shielding plate, its detected value is compared with a reference value set in advance, and when it reaches its reference value, a driving signal is outputted to a driving means of a replacing or cleaning member of the discharge wire from a comparing means, and a replacement or cleaning of the discharge wire is executed. In such a way, an unnecessary replacement or cleaning of the wire is not executed, and the discharge wire can be held correctly. |
