HIGH VOLTAGE AC POWER SOURCE PROVIDING WITH VARIABLE DC BIAS POWER SOURCE

摘要

A circuit for concurrently producing regulated high-voltage a.c. current and automatically varying d.c. current on one output line, where all adjustment and regulation is accomplished in low-voltage circuits, power supply being particularly useful as the power source for copier and duplicator corotrons. The basic wave shape is a rectangular wave which is amplified and regulated for application as the a.c. input to a corotron. The corotron itself is used as the rectifier for the d.c. bias current, and while the nominal d.c. bias is fixed by adjusting the duty cycle of the rectangular wave to a fixed value, the actual d.c. bias current will vary in accordance with atmospheric conditions and paper thickness, which is desirable for the proper operation of copier and duplicator corotrons. The adjusted duty cycle of the rectangular wave determines the nominal d.c. bias current. This is because the part of the corotron input wave shape which has the shorter duration must have the higher amplitude, and current in the corotron increases with voltage.