Panasonic UF-5500, Service Manual

Page: 55 / 365

55
UF-5500 / 4500
6.12.3. Exit Sensor
This sensor detects whether the recording paper exits or not.
When there is a recording paper at the position of the sensor, the input signal of IC300-AD20pin becomes low level.
When there is no recording paper at the position of the sensor, the input signal of IC300-AD20pin becomes high level.
6.12.4. Read Position Sensor
This sensor detects the front edge of the document.
When the front edge of the document is detected, the shelter plate closes the sensor light.
So the photo-transistor turns off and the input signal of IC300-AD22pin becomes high level.
When the front edge of the document is not detected, the shelter plate lets the sensor light pass.
So the photo-transistor turns on and the input signal of IC300-AD22pin becomes low level.
Signal (IC300-AD20pin)
A paper exists Low level
No papers High level
Photo-transistor Signal (IC300-AD22pin)
A document exists OFF High level
No document ON Low level
Shelter Plate
IC300
3
2
1
2
CN508 CN53
R510
AD20
R506
PS50
+3.3V
C508
Fuser Board
[Exit sensor]
+3.3V
Main Board
R54
1
2
Toner Board
CN64
3
2
CN65
Shelter Plate
IC300
2
1
2
1
CN700
R703
AD22
R706
+3.3V
C704
ADF
Board
Main Board
CN56
[Read position sensor]
PS53
R52
+3.3V