Canon DADF-N1, Service Manual

Page: 46 / 199

Chapter 2
2-24
2.3.7 Original Size Final Identification
0006-2261
The machine performs original size final identification with reference to the length of the
original (conversion result based on the feed motor drive used to move the original past the
read sensor (PI3)) and the result of original size initial identification.
When an original moves past the original detecting lever of the read sensor (PI3), the
detecting lever operates in conjunction with the light-blocking plate to permit the light to
the photointerrupter to pass. The machine refers to the clock pulses from the main motor
(M1) from when the read sensor (PI3) goes on to when it goes off to find out the feed length,
which will cause the read sensor (PI3) to generate the last original detection signal (ENDS)
for transmission to the ADF controller PCB.
F-2-18
The following shows the default sizes that are identified by the machine based on the results
of its size identification mechanisms:
<AB-Configuration Mixed Size Mode>
ADF controller PCB
Original
Detecting lever
PI3
READS