Ricoh FW870, User Manual

Page: 24 / 206

When the original lead edge sensor [D]detects the leading edge of the
original, the roll feed motor and the roll feed clutch turn on, and paper feed
starts. The original is fed to the original registration sensor [E] and stops at 33
mm [F] ahead of the original registration sensor to wait for the copy paper.
The registration clutch is activated at the appropriate time after paper feed
begins. The copy paper is fed to the registration roller [G] and the registration
clutch turns off when the copy paper reaches 15 mm [H] ahead of the
registration sensor [I]. The speed of the roll feed motor is increased from 90
mm/s to 162 mm/s to form a paper buckle [J]. Then, the speed of the roll feed
motor returns to 90 mm/s and the registration clutch turns on again. The
paper feed resumes and the copy paper is transported to the drum [K].
At the appropriate time, the original feed motor rotates again and the original
is delivered to the exposure glass.
To measure the original length for synchro-cutting, the copier CPU counts the
time after the original lead edge sensor [D] detects the leading edge of the
original until the original set sensor [A] detects the trailing edge of the
original. The copy paper length is measured by counting the number of steps
as the roll feed motor (stepper motor) turns. The roll feed motor stops at the
appropriate time and the cutter motor rotates to cut the copy paper.
Repeat copies
When making repeat copies, to increase the CPM, the roll feed motor starts
rotating 0.22 s after the roll lead edge sensor [L] is de-activated and advance
the copy paper 20 mm [M] (140 mm ahead of the paper feed start position).
After the 1st copy job, at the appropriate time after the trailing edge of the
original passes the original registration sensor [E], the original feed motor
rotates reverse 3.6 times as fast as the normal speed. The original is
returned to the position [N] where the leading edge of the original is 8 mm
before the original registration sensor.
When the leading edge of the original passes the original registration sensor,
the original feed motor rotates forwards again and the original is delivered to
the exposure glass and the copy job is repeated at the trigger timing. After
all the repeat copies have been made, the original is fed out.
After original scanning, the original can be stopped and caught by the original
exit rollers [O] or it can be fed out without being caught in the original exit
rollers. This is determined by SP No.24 (Original Hold mode). If the original
hold mode is selected, the original is fed out when the Clear/Stop key is
pressed or the next original is inserted.
Det
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Descript
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25 July 1996 EXPOSURE
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