Transfer Unit; Outline Of The Transfer Unit; Outline; Controlling The Transfer Bias - Canon iR2030 Series Service Manual

Chapter 6

6.8 Transfer Unit

6.8.1 Outline of the Transfer Unit

6.8.1.1 Outline

The transfer unit consists of a transfer roller [1] and an static eliminator [2].
The transfer roller is driven by the photosensitive drum.
The static eliminator is biased to separate paper from the drum.

6.8.2 Controlling the Transfer Bias

6.8.2.1 Transfer Roller Bias Control

A negative bias, sheet-to-sheet bias, or positive bias is applied to the transfer charging roller according to the type of sequence.
The negative bias is applied at the prescribed timing to moves the toner from the transfer charging roller to the photosensitive drum for cleaning.
The sheet-to-sheet bias is lower than that applied during printing and it is applied at the prescribed timing to prevent the toner remaining on the photosensitive drum
from adhering to the transfer charging roller.
The positive bias is applied to transfer toner images from the photosensitive drum to paper.
6-8
High-voltage power supply PCB
DC
controller
PCB
/TRPWM
ASIC
/TRPFOT
TRCHG
Constant current/voltage
switching circuit
/TRNFOT
CPU
TRCRNT
[2]
[1]
F-6-12
Transfer bias circuit
Comparison Positive current
circuit detection circuit
Positive voltage
generation circuit
Superimposition
Negative voltage
generation circuit
F-6-13
Tr3
To transfer
charging roller
0017-4355
0017-4356