Driving And Controlling The High-Voltage System; Outline; Drum Unit; Outline Of The Drum Unit - Canon iR2030 Series Service Manual

6.4 Driving and Controlling the High-Voltage System

6.4.1 Outline

iR2022i / iR2025 / iR2030 / iR2018 / iR2022 / iR2018i
The voltage generated by superimposing the DC voltage over the AC voltage is applied to the primary charging roller and developing cylinder, and a positive or
negative DC voltage is applied to the transfer charging roller according to the instruction of the CPU on the DC controller PCB.
The primary DC bias and developing DC bias are changed according to the image density information sent from the image processor PCB, thus adjusting the image
density.
A negative DC voltage is applied to the electrostatic discharge needle and fixing film.

6.5 Drum Unit

6.5.1 Outline of the Drum Unit

6.5.1.1 Outline

iR2022i / iR2025 / iR2030 / iR2018 / iR2022 / iR2018i
Major components of the drum unit are as follows:
[1] Photosensitive drum
[2] Cleaning blade
[3] Primary charging roller
DC controller
PCB
J214 J100
ASIC
CPU
[2]
High-voltage power
supply PCB
JP5/JP6
Fixing film bias
circuit
JP3/JP4
Primary bias
circuit
JP9/JP10
Static eliminator
bias circuit
Tr3
Transfer bias circuit
Developing bias JP7/JP8
circuit
JP1/JP2
Remaining toner
level detection circuit
F-6-6
[3]
[1]
F-6-7
Chapter 6
0017-4333
0017-4348
6-5