- HP Printer User Manual

ENWW Original feed/conveyance/exit section 17
ADF unit explanation
and original exit reversal roller to convey the
original to the reversal section. Each of
these features is controlled by PRCB (printer
control board) and driven by SCDB (scanner
drive board).
1 Operation
a Original ejection operation
During the single side copy mode and
when copying the front side in the
double side copy mode, the original exit
gate lifts upward because SD302 (exit
gate drive SD) is turned off. Therefore,
scanned original is ejected to the
original exit tray by the action of the
original exit roller. PS303 (original exit
PS) detects the original ejection.
b Reversal operation for double side
original copy
1 The first sheet of original
When PS304 (original registration/1)
turns on and pre-feed of the original
has completed, SD301 (reverse gate
drive) receives a signal from the MFP
and turns on to open the reverse
gate. M301 (original feed) rotates
forward (MC301 (original feed MC) is
on), and the registration roller,
reversal roller, and original exit
reversal roller convey the original to
the reversal section at high speed,
passing through the reverse gate.
M301 stops when a specified time
has passed after PS304 has detected
the trailing edge of the original. (The
original is conveyed to the reversal
section until the trailing edge crosses
over the reverse gate.) During this
time, SD301 turns off and the reverse
gate closes.
2 Second and subsequent original
When PS305 (original registration/2)
detects the trailing edge of the front
side of the first original, SD301
(reverse gate drive) turns on to open
the reverse gate.The second and
subsequent originals are thus
conveyed to the reversal section in
the same manner as the first original.
c Feeding the back side
When the reversal operation for the
double-side copy mode described
above has completed, high speed
backward rotation of M301 (original
feed) (MC301 (original feed MC) is off)
conveys the original to the read section
by the action of the reversal roller and
the original exit reversal roller. When
M301 rotates backward, SD302 (exit
gate drive) turns on to lower the original
exit gate, and the original exit path
switches from the original exit tray to the
reversal exit. When the specified time has
passed since PS305 (original
registration /2) is turned on by detecting
the leading edge of the original, SD303
(pressure roller release SD) turns on
temporarily according to the original
size. By SD303’s turning on, the
pressure on the original exit reversal
roller is released. This enables the
leading edge and the trailing edge of the
original to pass each other. When a
specified time has passed since the
back side of the original starts to be
scanned, SD303 turns off, at the same
time, M301 has been switched to low
speed forward rotation (MC301 is off).
The original exit reversal roller rotates in
the reverse direction, and the original is
conveyed to the reversal exit again. As
soon as scanning of the back side of the
original has completed, SD302 turns off,
and after the predefined time, M301 is
switched to high speed rotation. It stops
after the specified interval.
d Feeding the front side of the original
The original, which is conveyed to the
reversal section, is conveyed to the
read section again in order to scan the
front side. Since SD302 (exit gate drive)
is off, the scanned original is ejected to
the original exit tray.