Paper Detection And Printing Pressure On/Off Mechanism - Ricoh Priport VT 6000 Service Manual

PRINTING 29 January 1998
2.4.2 PAPER DETECTION AND PRINTING PRESSURE ON/OFF
MECHANISM
[A]
[B]
[C]
[D]
[E]
[G]
[F]
C228D507.WMF
When the paper is detected by the paper registration sensor [A], the printing
pressure solenoid [B] is energized. The stopper arm [C] then disengages the
pressure on/off lever [D]. The pressure on/off lever, which is connected to the end
of the press roller arm [E], starts moving when the printing pressure cam [F] starts
moving; the cam moves bearing [G], which is on the lever. The press roller is
pressed against the ink roller.
The printing pressure solenoid is de-energized when the printing pressure sensor
is activated; this is soon after it is energized. The stopper arm [C] returns and is
pressed against the pressure on/off lever, due to tension from a spring. (The
stopper arm just rides on the edge of the pressure on/off lever at this time.) To
finish applying the printing pressure, the bearing [G] on the pressure on/off lever is
pushed by the printing pressure cam and the lever turns clockwise, until it is
engaged by the stopper arm.
If the next sheet of paper is detected by the registration sensor within a certain
period, the printing pressure solenoid is again energized to disengage the pressure
on/off lever. The printing pressure for the next sheet of paper starts being applied.
If the registration sensor is not activated, the machine detects a paper misfeed
condition (Location B Misfeed). In this case, the printing pressure solenoid stays
de-energized and the printing pressure is not applied. This can prevent the press
roller contacting the drum (without paper) and getting ink on it because of the
paper misfeed.
NOTE: In the C223, Location B Misfeed was detected when the printing pressure
sensor was not activated within a certain period.
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