Canon DADF-J1 Service Manual page 71

3) The 1st original is moved over a specific length by the feeding belt after its leading edge
has moved past the post-registration roller paper sensor (S3) and held in wait.
(The DADF starts to keep count of the distance the 1st original moves after it has moved
past the pre-registration paper sensor (S2).)
Pre-registration paper sensor (S2)
Post-registration roller
paper sensor (S3)
4) The feeding belt is rotated to move the original for a specific distance.
When the 1st original has moved a specific distance (in reference to the count kept since
its trailing edge has moved past the pre-registration roller sensor (S2), the DADF issues
the image leading edge signal to the copier. In response to the image leading edge sig-
nal, the copier starts reading of the original.
At this time, the 2nd original is also moved and is kept on hold in wait position.
Pre-registration roller paper sensor (S2)
COPYRIGHT © 2001 CANON INC.
Wait position
F02-206-17
2nd original
F02-206-18
2000 2000 2000 2000 CANON DADF-J1 REV.0 MAR.2001
CHAPTER 2 OPERATIONS AND TIMING
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