Canon DADF-Q1 Service Manual page 50

Chapter 2
2) The machine rotates the registration roller and the transport belt to move the original.
When the trail edge of the 1st original leaves the pull-off roller, the machine starts pickup of the 2nd original.
3) When the lead edge of the 1st original has moved past the post-registration roller paper sensor (S3), the machine moves it over a specific distance using the
transport belt and stops it (at standby position). (At this time, the machine starts to keep track of the distance over which the 1st original moves after it has moved
past the pre-registration roller sensor (S2).)
4) The machine rotates the transport belt to move the original over a specific distance. The host machine reads the original.
When the machine has moved the 1st original (based on the count reading started after the trail edge of the original has moved past the pre-registration roller paper
sensor (S2)), the machine sends the image lead edge signal to the host machine.
In response to the signal, the host machine starts to read the original.
At this time, the machine starts to move the 2nd original.
5) The machine rotates the transport belt to move the 2nd original. If the read signal arrives from the host machine before the 2nd original reaches the front position
(25 mm + stop distance), the machine does not stop the original for reading. If the signal does not arrive before the original reaches the front position (25 mm +
stop distance), on the other hand, the machine stops the original in standby position and then rotates the transport belt for reading of the 2nd original.
6) The machine goes back to step 2. above and repeats the subsequent steps.
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Pull-off roller
Pre-registration roller sensor(S2)
Post-registration
Standby position
roller paper sensor(S3)
Pre-registration
roller paper sensor(S2)
2nd original
2nd original
2nd original
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F-2-51
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