Stabilizing The Scanning Lamp(Ir105); Controlling The Temperature By A Fluorescent Lamp Heater - Canon ImageRunner iR8500 Series Service Manual

Chapter 5
Related Service Mode
COPIER>ADJUST>LAMP>L-DATA
(scanning lamp light intensity data input)

5.3.3.2 Stabilizing the Scanning Lamp(iR105)

iR105
A transformer PCB has been added to increase the voltage supplied to the inverter power supply from 38 to 40 V so that the intensity of the scanning lamp
remains stable.

5.3.3.3 Controlling the Temperature by a Fluorescent Lamp Heater

iR105i/iR105+ / iR9070
The fluorescent lamp controls the area around the fluorescent lamp to 70 deg C to ensure a stable
light intensity.
5-16
Reference intensity level for comparison against FL-DTCT.
When '0' ,the scanner heater turns on.
Difference between FL-REF and FL-DTCT. FL-PWM is corrected based on this data.
Light intensity control PCB
1 2 3 4 5 1 2 3 4
J853
Relay PCB
1 2 3 4
Transformer PCB
FL-GAIN
1
HEAT-ON
2
FL-TH
3
0 V
4
FL-REF
5
0 V
6 6
FL-CLK
7 7
FL-ERR
8 8
PRH-ON
9 9
PRH-PWM
10 10
FLON
11 11
0 V
12 12
FL-PWM
13 13
J506B J1002
Inverter PCB
Pulse signals used to drive the transformer (T1001).
Error detection
When '0', pre-heat voltage is applied.
Pulse signals. Changing the pulse width increases/decreases the pre-heat voltage.
When '0', the fluorescent lamp turns on.
Pulse signals. Changing the pulse width increases/decreases the intensity of light.
J852
24 V
1
FL-DTCT
2
GND
3 To light intensity sensor
38 V
4
GND
To temperature sensor/scanner
5
heater
FL-TH
6
Fluorescent lamp
J851
heater temperature
Stabilizing the amount of
light of the scanning lamp.
Voltage rises from 38V to
40V.
J1001
1 2
T1001
Fluorescent
Transformer
lamp
drive control
transformer
Activation
voltage
Pre-heat voltage
Pre-heat
output
control
Output Current
control
detection
F-5-23
T-5-12
Use it to enter the setting recorded on the
service label if the result of CCD-ADJ is NG,
thereby determining FL-PWM.
Settings: 0 to 255
Higher setting
Lower intensity
Lower setting
Voltage to suit the light intensity.
H5
Temperature
sensor
1
2
3
4
5
J803
Light
intensity
Scanning
sensor
lamp
Fluorescent
heater
Higher intensity
0006-9538
0006-9428