Xerographic process control using periodic electrostatic set up to automatically adjust charging potential

摘要

An image processing apparatus having a corona device (14) for charging a photoreceptor (12) to voltage levels, a developer (20) for applying toner to the photoreceptor, and a sensor (22) for providing a signal in relation to photoreceptor voltage for adjusting the photoreceptor voltage levels by providing signals from the sensor in response to periodic electrostatic set ups which includes developing a series of predetermined test patches on the photoreceptor, relating the signals to characteristics of the photoreceptor, adjusting (28,30) the corona device for said characteristics in response to said signals, and measuring cycle down and short term photoreceptor rest recovery changes in photoreceptor voltage for use in adjusting the corona device.