Transfer Charging Mechanism; Outline; Controlling The Output To Suit The Environment (Fuzzy Control) - Canon ImageRunner iR8500 Series Service Manual

Chapter 8
Related Service Mode
COPIER> OPTION> BODY>
TRNSG-SW
(transfer guide bias control mode
switching)

8.7.2 Transfer Charging Mechanism

8.7.2.1 Outline

iR105i/iR105+ / iR9070 / iR85+ / iR8070
The transfer charging mechanism is controlled for the following:
[1] DC bias constant current
[2] Output to suit the environment (fuzzy control)
[3] Output correction at the trailing edge of paper
Figure shows the construction of the transfer charging control system.
When '1', high voltage output is ready.
A voltage input between 0 and 12 V,
used to control the transfer current
output.

8.7.2.2 Controlling the Output to Suit the Environment (fuzzy control)

iR105i/iR105+ / iR9070 / iR85+ / iR8070
The transfer current output is controlled to an optimum level to suit the environment (conditions identified based on the data from the environment
sensor).
8-32
0: switches to +200 V in high humidity. (default)
1: fixes the transfer guide bias to +600 V.
2: fixes the transfer guide bias to +200 V.
3: switches to +200 V in normal humidity.
4: switches to +200 V in low humidity.
If transfer faults occur, select '2' through '4'.
Relay PCB
1 2 3 4
J510A
0 V
1 1
HVDC-EN
2 2
3 3
4 4
5 5
TR-CNT
6 6
TR-ERR
7 7
8 8
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
When an overcurrent or
an under current is
detected, '1'.
T-8-20
T701
The transfer current varies as follows
according to the TR-CNT potential.
-650µA
F-8-44
Transfer charging wire
TR-CNT
3V
11V 12V
0006-9754
0006-9756