Overview; Overview Of The Electrophotographic Printing - Epson EPL-N3000 Service Manual

EPSON EPL-N3000/AcuLaser M4000N

2.1 Overview

2.1.1 Overview of the Electrophotographic Printing

This printer uses electrophotographic printing method to print images on paper by
using the video signal transmitted from the Main Board Assy to the MCU of the
HVPS/MCU. Electrophotographic printing method consists of the seven steps as
described below:
1. Charging:
The BCR (Bias Charge Roll) generates a uniform negative charge on the drum
surface.
2. Exposure:
The Laser Scanner scans the surface of the drum using extremely thin laser
beam modulated according to the signal from the controller, and generates an
invisible latent image on the surface of the drum.
3. Development:
Toner is attracted to the electrostatic latent image on the drum surface, and a
visible toner image is generated.
4. Transfer:
The toner image is transferred from the surface of the drum onto the paper.
5. Separation:
The paper is separated from the surface of the drum by partial neutralization
of the charge on the paper.
6. Fusing:
The toner image is fused to the paper by application of heat and pressure.
7. Cleaning:
Residual toner is removed from the surface of the drum.
As the drum turns, the surface of the drum passes the steps of charging, exposure,
development, transfer, separation and cleaning, so that the toner image is generated on
the surface of the drum and is transferred onto the paper.
The paper passes the steps of transfer, separation and fusing by the operation of the
paper transport mechanism. When the paper is positioned for the image, the toner
image is transferred from the drum surface onto the paper and then fused.
Operating Principles
Cycle repeats
for the next print
7. Cleaning
Figure 2-1. Overview of Printing Process
6. Fusing
5. Separation
4. Transfer
Figure 2-2. Components Related to Printing Process
Overview
Revision C
: Paper flow
1. Charging
: Transfer process
2. Exposure
3. Development
4. Transfer
Paper enters
5. Separation
6. Fusing
Ejecting printed paper
7. Cleaning
1. Charging
2. Exposure
3. Development
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