Xerox Phaser 6280, Service Manual, Page: 66 / 672

2-4 Phaser 6280 Color Laser Printer Service Manual
Theory of Operation
Charging
The Drum surface is charged with negative electricity by discharging of the
Bias Charge Roll (BCR) while rotating at a constant speed. This process is
performed in parallel for Cyan, Magenta, Yellow, and Black colors.
The BCR is kept in contact with the Drum and rotates following the rotations of
the Drum. The BCR is a conductive roll, which receives negative voltage from
the High-Voltage Power Supply (HVPS) and discharges a negative Direct
Current (DC) voltage.
The Drum surface is uniformly and negatively charged with DC bias voltage.
The Drum surface is a photoreceptor (which is an insulator in a dark area and
a conductor when receiving light) and the Drum inside is composed of
conductor.
The BCR Cleaner contacts with the BCR to catch the toner.
s6280-047
Cleaning Roll
BCR
Photoreceptor
Conductor
Drum
HVPS
s6280-048
Drum Surface
s6280-049
Electrical Potential
on Drum
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