Lexmark C925 - Page 37

Lexmark C925/X925 Color Product Study Guide Rev 2.3
For Training Purposes Only 6/21/2011
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• Once the trailing edge of the scan media reaches the ADF scan sensor, the sensor moves to
the off position and the image acquisition process continues for a pre-calculated length of
time.
• After the scan is complete, the trailing edge of the media continues to the reverse point where
the duplex gate is positioned by a solenoid to direct the paper to the pass through sensor.
• As the paper reaches the paper pass sensor, the sensor does two things:
- It determines if a jam has occurred (based on the time it takes for the paper to pass
through the sensor).
- It determines the position of the paper in the ADF paper path based on the size of the
paper in the scan job.
o Once the sensor determines that the paper has left the ADF paper path, a signal
is sent to move the duplex gate so the paper may enter the duplex paper path.
o A second signal is sent to trigger the gear solenoid to move the reversing gear
assembly into place. This reverses the direction of the duplex paper rolls and
creates a peek-a-boo effect by pulling the exiting paper back into the duplex
paper path.
o If the scan job is simplex, the duplex gate is positioned to direct the media to the
exit roller and the media exits the ADF to the output bin.
• The transport roll moves the media through the duplex paper path to the paper in sensor.
• When the paper in sensor is actuated, the exit roll stops reversing and signals that that this is
the second side of the media to be scanned.
• The imaging process is repeated for the other side of the paper. After the image is created,
the paper proceeds to the paper pass sensor a second time.
• When the trailing edge of the media reaches the reverse point for the second time, the
solenoid moves the duplex gate to the down position and reverses the exit roll. The paper
reverses back into the ADF unit for a third time.
• The paper passes through the paper path, but no imaging occurs. This pass turns the paper
over to the original side up.
• Once the trailing edge of the media reaches the reverse point the third time, the solenoid is
not actuated. The paper proceeds to the exit rolls and passes out of the ADF to the exit bin.