Printronix L5535, Руководство по обслуживанию

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Printing Operations
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loading, before asserting the image data (video signal) request VSYNC
signal. In drum cleaning, the following routine is executed.
a. The drum motor starts running, and the discharge lamp lights at the
high power level.
b. The main charger and precharger simultaneously turn ON when drum
rotation is stabilized.
c. The cleaning bias turns ON when the precharged drum surface area
comes into contact with the conductive brush.
d. As the charged portion of the drum surface passes the developing
roller, the magroll motor (developing roller inner-pole magnet drive
motor) and sleeve motor (developing roller sleeve drive motor) start,
and the developing bias turns ON.
e. When the drum has made two revolutions, the discharge lamp light
intensity drops.
f. Cleaning terminates when the drum makes another revolution.
2. Paper loading.
The tractor starts running to load the paper in such a manner that the
paper leading end is positioned 1/2 inch before the transfer point.
3. VSYNC (vertical sync) signal assertion.
This operation is performed to inform the controller of completed
preprocessing and to make a request for image data. At the same time,
the main unit feed motor, vacuum fan motor, and paper fanfolding unit
(optional) start operations. However, the main unit feed motor starts
running at the high speed to render the paper transport speed slightly
higher than the drum rotation speed, thereby avoiding paper slackness at
perforation. Note that the drum motor, discharge lamp, main charger,
precharger, cleaning bias, magroll motor, sleeve motor, and developing
bias have already been turned ON in the process of drum cleaning prior
to printing (1).
4. LED exposure.
When the controller receives the VSYNC signal, it waits until the printer
asserts the page leading-edge margin SYNC (raster sync) signal, and
then asserts the video signal acquisition VGATE (video gate) signal and
VDO (video) signal. The VGATE signal is successively asserted for
individual horizontal scan periods. However, the VDO signal is asserted
only for the pixels to be printed. When the VDO signal is asserted, LED
illumination occurs.
5. Tractor actuation.
The paper is transported to the transfer point when the drum exposure
surface arrives at the transfer point.
6. Transfer unit ascent.
When the paper leading edge arrives at the transfer point, the transfer
unit ascends.