Document Detection; Outline - Canon DADF-AA1 Service Manual

Chapter 3
Start of reading of reverse side
of second document sheet
End of reading of reverse side
of second document sheet
Stop after feeding the second
document sheet to reversal position

3.3 Document Detection

3.3.1 Outline

This machine detects a document using either of the two methods depending on the print mode.
- Normal print mode (other than mixed size print mode and banner paper mode)
- Mixed size print mode and banner paper mode
a. Normal print mode (other than mixed size print mode and banner paper mode)
In the normal print mode, the following four document detection functions are used:
Document presence/
absence detection
Last document detection
Initial document size
detection
- Longitudinal direction
- Lateral direction
3-8
Function Description
Detects whether there is a document on the
document pickup tray.
Detects whether the document being picked up is
the last one.
Detects the length of the document placed on the
document pickup tray.
Detects the width of the document placed on the
document pickup tray.
Removal of idle reversal registration
loop of second document sheet and
release of re-pickup/delivery roller
Pressurization of second document
sheet delivery roller
Completion of delivery of second
document sheet and end of job
F-3-8
Sensor used (symbol)
Document set sensor (SR5)
Last document detection sensor
(SR7)
Document length sensor 1/2
(SR9/SR8)
Document width sensor 1/2 (PS2/
PS1)
0024-6988