Ultrasonic Double Feed Detection; Jam Detection - Canon imageFORMULA DR-X10C Service Manual

5. Ultrasonic Double Feed De-
tection
There are 2 double feed detection meth-
ods: the document length detection by the
registration sensor
overlapping detection by the ultrasonic sen-
sor.
This section describes the ultrasonic
sensor.
This machine contains 3 pairs of ultra-
sonic sensors in front of the registration roller.
A layout drawing is shown below.
Registration roller
60mm 60mm
Figure 2-309
The ultrasonic drive sensor transmits the
ultrasonic and the ultrasonic receive sensor
receives the ultrasonic signal to gain a spe-
cific signal level. When overlapping docu-
ments are fed, the signal level is different from
when properly feeding a single document.
This machine interprets this difference as a
"double feed". The double feed detection by
ultrasonic may not work if the document
overlapping width is 50 mm or less.
Ultrasonic receive sensor
(reception)
Ultrasonic drive sensor
(transmission)
Figure 2-310
COPYRIGHT © CANON ELECTRONICS INC. 2008
and the document
Ultrasonic sensor
Separation roller
Document feed
CANON DR-X10C FIRST EDITION
CHAPTER 2 FUNCTION & OPERATION

6. Jam Detection

Document jams are detected by the reg-
istration sensors (front and rear) and the eject
sensor.
1) Pickup Delay Jam (Pickup Error)
The leading edge of the document was not
detected by the registration sensor within
the specified time after the machine starts
pickup.
2) Early Reach Jam
The leading edge of the following docu-
ment was detected after the trailing edge
of the document was detected by the reg-
istration sensor before the document has
been fed for a specified length.
3) Residual Jam
The trailing edge of the document was not
detected even though the document has
been fed for the maximum specified length
after the leading edge of the document
was detected by the registration sensor.
4) Fast Feed Jam
The trailing edge of the document was
detected after the leading edge of the
document was detected by the registration
sensor before the document has been fed
for the minimum specified length.
5) Eject Jam
A pickup delay jam and a residual jam
were detected by the eject sensor.
6) Non-removal Jam
When the power was turned ON or the
upper unit was opened or closed, the
document was detected by the registration
sensor.
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