Toner Density Control (Adc) - Epson ColorPage EPL-C8200 Service Manual

EPSON ColorPage EPL-C8200

2.7.5.3 Toner Density Control (ADC)

To obtain stable print quality, it is necessary to maintain constant toner
density in the developer. (The toner density must be detected correctly
in the actual developer without being affected by the laser.) The ADC
(Auto Density Control) forms BIAS development bands (for each color:
YMCBk) on the drum and measures the density of the bands with the
ADC Sensor. (The BIAS development bands are formed with the
standard BCR voltage and development voltage and are different from
the printing voltages.)
Chapter 2 Operating Principles
When detecting low toner, the system rotates the Dispense Motor
(Dispense Motor Assembly) (driving the Auger in the Developer
Assembly) for the calculated duration (dispense time) to supply toner to
the Developer Assembly from the Toner Cartridge. If too much toner
(toner density in the developer is too high) is detected, the system forms
numbers of BIAS development bands to consume the toner until the
right toner density is detected.
NOTE: The BIAS development bands are images developed on the
Figure 2-44. Toner Density Control (ADC)
BCR charged area that has negatively charged toner. This is
done by raising the BCR voltage higher than the development
voltage.
Revision A
2-51