Canon F-1, Service Manual

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Technology > Controls > DADF > Original Size Detection
Technology > Controls > DADF > Original Size Detection
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Original Size Detection
● Overview
The following shoes the detection list of original size.
Timing Direction Sensor
Mode
Normal
Mix of same
specification
Mix of different
configuration
Extra
long
Start of
pickup
Feed
LTR-R/LGL
identification sensor
(SR8)
Yes - - -
Width
AB/ Inch identification
sensor (SR7)
Yes Yes - -
Original width volume
(VR)
Yes Yes Yes Yes
In feeding
Feed
Post-separation
sensor 3 (PCB2)
Lead sensor 1 (PCB4)
Yes Yes Yes Yes
Width
Original size sensor 1
to 4 (SR17 to 20)
- - Yes -
Note:
• Normal/mix of same configuration/mix of different configuration mode:
measurement value is converted to standard size.
• Extra long mode / (non-plain detection):
Measurement value is used for original size as it is.
T-2-15
● Detection at Start of Pickup
Detection in feed direction
The size of original is determined whether it is LTR-R or LGL by LTR-R/LGL identification
sensor (SR8).
Once an original is placed on the original pickup tray, the light-blocking plate operates in
keeping with the detection lever of LTR-R/LGL identification sensor (SR8) and blocks the light
of photo interrupter.
With reference to the signal (LGL_S) of the LTR-R/LGL identification sensor (SR8) and the
original width, the machine determines whether or not the paper on the original pickup tray is
LGL.
The machine communicates the original size information with the connected devices as soon
as the start key is turned ON.
SR8
LGL_S
LGL size original
Detecting lever
DADF driver PCB
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