METHOD FOR STABILIZING ELECTRIFICATION OF ELECTROPHOTOGRAPHIC SENSITIVE BODY

摘要

PURPOSE:To enable compensation of electrification which can deal satisfactorily with continuous copying for a long period and intermittent copying by providing separately a function in the stage of continuous copying indicating the restoration process of fatigue of a selenium photosensitive layer arising from copying operations and a function during stoppage of coppying and providing further two time constants into each function. CONSTITUTION:The max. quantity of compensation is proportional to the varying quantity of a decrease in electrification in one cycle. The compensation of electrification of the case when continuous copying is continued from the state having no fatigue is calculated by a compensator 1 and the value of the corona current ic to be increased for the purpose of compensation corresponding to the result of the calculation (the total quantity of the decrease in the electrification during operation) is applied as a compensatioin signal 1a to a DC high-voltage power source 2 from a digital-to-analog conerter of the compensator 1. The power source 2 compensates the electrification by increasing the corona current ic. The function as the coefft. to indicate the time dependency of the fatigue restoration during stop time of copying can be freshly assumed or the initial quantity of compensation of electrification at the point of the time for restarting copying when there is the stop period for copying and this function is expressed by the equation in the same way as in the case of continuous copying. The above- mentioned calculation is executed by the compensator 1 during the actual copying operation of the copying machine.