Controlling The Developing Bias; Operation - Canon CLC 1120 Service Manual

CHAPTER 6 IMAGE FORMATION SYSTEM
B. Controlling the Developing Bias

1. Operation

The developing bias control mechanism has the following items of control:
1. Controlling the developing bias AC component to a constant voltage.
2. Controlling the developing bias DC component to a constant voltage.
Each of the signals is used for the following:
[1] Controlling the Drive of the Developing Bias PCB
When DBSBY is '1',
The reference voltage generation circuit turns on and the developing bias PCB cooling fan
drive circuit turns on.
Power is supplied to each circuit, and the developing bias PCB cooling fan turns on.
DC driver PCB
J1001
-A6
-A5
-B7
-B6
-A2
-B3
-A4
-A3
-B5
-B4
-A7
6-18
COPYRIGHT © 1999 CANON INC.
[2]
DBS1 (M)
[2]
DBS2 (Y)
[2]
DBS3 (C)
[2]
DBS4 (BK)
[3]
DBBPC1 (Y,M)
[3]
DBBPC2 (C,BK)
[4]
DBDCC1 (Y,M)
DBDCI1 (Y,M) [5]
[4]
DBDCC2 (C,BK)
[5]
DBDCI2 (C,BK)
[1]
DBSBY
Figure 6-302
CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Developing bias PCB
J401-3
J401-4
J402-1
J402-2
J401-7
J402-5
J401-5
J401-6
J402-3
J402-4
J401-2
Developing
cylinder
Y
C
M
Bk