公开(公告)号：CA1114012A

公开(公告)日：1981-12-08

申请号：CA307365

申请日：1978-07-13

Applicant: IBM

Inventor： BACON JAMES L ,  ERNST LARRY M ,  HAUPTMAN WILLIAM G

IPC: G03G13/02 ,  G03G15/02 ,  G03G21/00

Abstract: An improved regulated power supply for a Corona Charging Unit. More specifically, a digitally regulated power supply for the corona charging unit of an electrostatic copying machine in which a sample of the ionic current of the corona unit is utilized in conjunction with digital regulator means to regulate the power supply means establishing the charge of the corona. The digital regulator means in conjunction with at least one pulse width modulated power supply permits very fast rise and fall times of the power supply current. Thus, the ability to switch "corona's" on and off in an area of the photoconductor much narrower in width than the width of the corona unit is provided. Further, between duty cycles of the machine, the regulator stores a representation of the correct operating point of the corona charging unit determined in the immediately prior duty cycle. In the next duty cycle, the representation is utilized to initially regulate the power supply. The regulated power supply although having particular merit and utility when employed in a xerographic copier, or the like, also may be advantageously employed, with or without obvious modification in numerous other types of apparatus, e.g.. servomechanisms, printed circuit motor driver, Precipitrons. etc.