Overview Of Operation - Canon iR C6800 Series Service Manual

5.3.4.3 Overview of Operation

1. Standby
No.1 mirror base: shading position
xenon lamp: off
original sensor: off
2. ADF Opened
No.1 mirror base: shifts to original detection position
xenon tube: off
original sensor: off
3. ADF Closed
When the ADF is brought to 25 deg, the area covered by an original will be blocked from external light; therefore,
the machine will assume the absence of an original at points that detect external light (external search).
The ADF open/closed sensor 2 identifies the condition as being "closed," and the machine starts original size
identification.
At this position, B5, B4, A44, and A3 are excluded from the list of possible sizes.
The machine executes an external light search: for main scanning direction, it turns on the xenon lamp to check its
light (reflected) at 4 points using the CCD; for the sub scanning direction, the machine checks the state of the original
sensor.
Xenon lamp
Original sensor
Point of detection 1
ADF
Point of detection 2
Point of detection 3
Reader unit
Point of detection 4
Original detection position
F-5-20
(external
light)
F-5-21
(external
light)
F-5-22
25
F-5-23
Copyboard
glass
Chapter 5
0002-5153
5-15