Primary Charging - Canon imageRUNNER ADVANCE C255 Series Service Manual

No. Block name
4 Transfer block
5
6
7 Fixing block
8 ITB Cleaning Block
9 Drum cleaning block

Primary Charging

■ Overview
This machine uses the roller charging method for primary charging.
■ Primary Charging Bias Control
DC charging is a distinguishing feature of the primary charging of this machine.
The surface of the Photosensitive Drum is charged to make a uniform negative potential.
The primary charging bias (DC negative), which has been generated by the Secondary Transfer High-voltage PCB (UN02), is
applied to the Primary Charging Roller.
The primary charging bias value is determined by the DC Controller PCB based on the following conditions:
• Environment (humidity detected by the Environment Sensor (UN33))
• Life of the Photosensitive Drum
Process name
Primary transfer Toner on the surface of the Photosensitive Drum is transferred to the ITB
by applying positive charge from the back side of the ITB.
Secondary transfer Toner on the ITB is transferred to the paper by applying positive potential
to the Secondary Transfer Outer Roller.
Separation With the curvature separation method, the paper is separated from the ITB.
In the case of thin paper which has low elastic force, the Static Eliminator
reduces potential on the back side of paper to make the thin paper to be
separated easily.
Fixing The toner on the paper is fixed on the paper by heat and pressure.
ITB cleaning The Cleaning Blade removes the residual toner attached on the ITB.
Drum cleaning The Cleaning Blade removes the residual toner attached to the Photosen-
sitive Drum.
Description
Photosensitive
Drum
Primary Charging
Roller
53
2. Technology