Dust Detection; Overview - Toshiba e-STUDIO4500c Service Manual

SCANNER UNIT

6.5.5 DUST DETECTION

Overview

When an original is put on the original feed table of the ARDF, the ARDF exposure
glass is checked for dust.
The dust check is done before the first original is scanned. This is done only once
at the beginning of a job. The check is not done for originals added during a long
scanning job.
The ARDF transport belt turns with no paper fed across the ARDF scanning glass.
The surface (white) of the ARDF transport belt is scanned. The IPU checks if dust
is present.
If dust is detected, the scanner carriage position for ARDF scanning is moved by
0.7 mm.
The next time that dust is detected, the scanning position is moved again by 0.7
mm.
The third time that dust is detected, the scanning position is not moved. An alert
message is displayed but the job does not stop.
Then, at the start of the next job, the procedure starts again, but the scanner
does not go back to home position.
SP4020 001 ON
Start
Do dust detection?
YES
Dust Check Processing
Dust detected?
YES
3 turnovers?
NO
Scan Position Movement
Processing
NO
SP4020 001 OFF
NO
YES
Alert
display
Copying
6-36
August, 2006
No alert
display
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