Controlling The Attraction Charging Mechanism And Transfer Charging Current; Operations - Canon CLC 1120 Service Manual

CHAPTER 6 IMAGE FORMATION SYSTEM
C. Controlling the Attraction Charging Mechanism and Transfer
Charging Current

1. Operations

The attraction charging / transfer charging mechanism has the following items of control:
1. The attraction charging mechanism is controlled to a contact current.
2. The transfer charging mechanism is controlled to a constant current.
3. The current is controlled to suit the type of copy paper and the reading of the environment
sensor.
The CPU PCB performs appropriate current control to suit the type of transfer medium
(regulator, thick, transparency) and the temperature and humidity readings from the
environment sensor.
Each of the signals is used for the following:
[1] HVATC (attraction charging current ON/OFF control signal)
When '1', the charging output is ready.
[2] HVATI (attraction charging current level control signal)
Controlled to +8 to +16 V; at +16 V or less, the high-voltage output is generated.
[3] HVTRC (transfer charging current ON/OFF control signal)
When '1', the charging output is ready.
[4] HVTRI (transfer charging current level control signal)
Controlled to +8 to 16 V; at +16 V, the high-voltage output is generated.
DC driver PCB
J1012
-A4
-A3
-A6
-A5
6-20
COPYRIGHT © 1999 CANON INC.
[1]
HVATC
[2]
HVATI
[4]
HVTRC
[3]
HVTRI
Figure 6-303
CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
HVT-DC PCB
J411
-10
T305
-11
-8
-9
Transfer
charging
T304
Attraction
charging