| 摘要 |
PURPOSE:To maintain initial characteristics of a copying machine and to prolong its life by composing a developer deterioration detector of a comparing circuit which has one input connected to a detecting element and the other connected to a reference voltage terminal and a visual display means which displays the deterioration of a developer. CONSTITUTION:The output of the detecting element is supplied to one input terminal of the comparator 23 and a reference voltage is supplied to the other input terminal; and the comparator compares the output of the detecting element with the reference voltage to supply its output to the visual display means 24 when the output of the detecting element is higher than the reference voltage. The visual display means consists of lamps on the console panel of the copying machine and the lamps are turned on with the output of the comparator to display visually the deterioration of the developer to an operator with patterns or characters of covers which cover lamps. The quantity of copies, toner concentration after transfer on a photosensitive drum due to the deterioration of toner, and the density of fogging of the background part of the copy are calculated and compared with the reference voltage to judge the deterioration of the developer, and the comparator outputs the signal to the visual display means to display that. Consequently, initial characteristics of the copying machine are maintained and its life is prolonged. |
