1 Controlling The Primary Charging Roller Bias; Outline - Canon iR1600 Service Manual

CHAPTER 5 IMAGE FORMATION SYSTEM

2 1 Controlling the Primary Charging Roller Bias

2.1 Outline

The machine uses a charging roller for primary charging (direct charging method), and it
applies an AC bias to stabilize the charging in addition to the DC bias.
The following items of control are used in relation to the primary charging control system:
[1] turning on and of the bias.
[2] performing constant voltage control for the DC bias.
[3] performing constant current control for the AC bias.
The primary charging control system is constructed as shown in the following diagram:
DC controller PCB
DCPWM*
ASIC
PRDCFOT*
PRACFOT*
PRACON*
CPU
5-4
Primary charging circuit
Comparison
circuit
detection circuit
Comparison
circuit
detection circuit
To developing bias circuit
F05-201-01
COPYRIGHT© 22002 CANON INC.
Primary DC
bias voltage
DC generation
circuit
Superimposition
AC generation
circuit
Primary AC
bias voltage
2000 CANON iR1600/iR2000 REV.1 JAN. 2002
Pr TB401/TB402
To primary
charging roller