Pulsed High Voltage Dc Power Supply Improves Dc Corona Uniformity in Electrophotographic Copier and Printer Applications
Original Publication Date: 1989-Mar-01
Included in the Prior Art Database: 2005-Jan-27
The uniformity of negative corona emission can be improved by a slight modification of the secondary doubler network at the output of the negative high frequency high voltage power supply (Fig. 1.) No change in the corona hardware is required (but may be desirable for optimization. The circuit modification produces a high voltage negative (or positive) pulse that is added to the negative (positive) voltage generated by the doubler network. The pulse is produced by the addition of diode CR3, resistor R29, and capacitor C3. During the positive (Image Omitted) transition of the output voltage waveform from transformer T1 pin 4, capacitor C3 is charged through resistor R29 and diodes CR3 and CR1.