Epson EPL-N2050 Service Manual page 53

EPSON EPL-N2050
CRU (Electro-Photography):
The CRU is composed of six major components.
Drum:
An aluminum cylinder with a coating of
photoconductive material on the surface. The
photoconductive property of the drum allows the
drum surface to hold an electrical charge while in
darkness, and discharge it when exposed to the
light.
Bias Charge Roll (BCR):
Places a uniform electrical charge on the drum
surface. At the end of a print cycle, the BCR applies
an AC voltage to the drum surface to neutralize any
electrical patterns remaining from the last print
cycle.
Magnet Roll:
Distributes toner to the drum surface.
Charge Metal Blade (CM Blade):
Spreads an even coating of toner on the Magnet
Roll, and gives the Roll a static–electric charge.
Cleaning Blade:
Removes any residual toner left on the drum from
the last print cycle.
Drum Shutter:
When the CRU is in place in the printer and the Front
Cover is closed, the Drum Shutter opens to expose
the area of the drum surface that comes into contact
with the paper during a print cycle. When the CRU is
out of the printer or when the Front Cover is open,
the drum shutter closes to protect the drum surface
from light shock and contamination.
Operating Principles
Figure 2-22. Components of Drive & Electrophotographics
Figure 2-23. CRU Side View and Shutter
Overview
Revision B
53