Canon F-1, Service Manual

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Technology > Controls > Reader > Original size detection
Technology > Controls > Reader > Original size detection
b. Priority on the front original presence
As a result of main scanning direction measurement, if the original absence is detected at
the rear while the original presence is detected at the front, a priority is given to the result of
original presence at the front.
Point of detection 1
Point of detection 2
Point of detection 4
Point of detection 3
Point of detection 5
Scanner unit
original detection position
B5
Original
size
sensor1
Original detection position Result Identified size
1 Y Y
2 - Y
3 - Y
4 Y Y
5 - -
Judgment B5
* Signal change with DADF Open to Close
Change: -
Others: Y
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● Detection operation
Following is the overview of operation for original size detection (AB type).
1) Wait status
Scanner unit: shading position
LED lamp unit: OFF
Original size sensor: OFF
Original detection position
Scanner unit
Original size
sensor 1
Reader unit
DADF
Copyboard
glass
Point of detection 1
Point of detection 2
Point of detection 3
Point of detection 4
Point of detection 5
DADF open/closed sensor 2
DADF open/closed sensor 1
2) DADF opened (The angle of DADF is 25 degree or more).
Scanner unit: It moves to the original detection position (20mm from the original push-on
position)
LED lamp unit: OFF
Original size sensor: OFF
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