Lexmark 19Z0201 - X 862dte 4 B/W Laser, User Manual

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Chapter 8: Theory of operation
Theory of
operation
Your laser printer is a very complex machine, but the gen-
eral process that makes your image appear can be easily
understood. By understanding how your printer operates,
you can understand why problems occur and how to cor-
rect or prevent them. There are many components that
make your printer work, however, the carousel, print car-
tridge, transfer belt, second transfer roller, and fuser will
help you understand the basic process.
The information you send to your printer is changed into
a laser-emitted signal. This signal is projected onto a mir-
ror inside the print cartridge carousel. The image is then
bounced off the mirror and onto the photoconductor (the
green tube in your print cartridge). The photocondutor
becomes electrically charged by the laser signal. The posi-
tively charged photoconductor pulls toner from the toner
reservoir inside the print cartridge onto the photoconduc-
tor. As the carousel rotates, the photoconductor meets the
transfer belt.
The transfer belt has a uniformly negative charge on it.
When the transfer belt and photoconductor meet, the
transfer belt pulls the electrically positive charged toner
from the photoconductor onto the transfer belt. As the
transfer belt rotates toward the front of the printer, the
paper travels up the paper path to meet your image. The
paper and toner image on the transfer belt meet at the sec-
ond transfer roller located on the inside of the front cover.
The second transfer roller has a stronger uniform nega-
tively charged field than the transfer belt. The positively
charged toner image on the transfer belt is pulled from the
transfer belt into the paper by the second transfer roller.
The paper travels up the paper path to meet the fuser. The
fuser uses heat and pressure to make toner adhere to the
paper. The result of these components working together is
the sharp laser image you want.
To get the best possible output, use the correct media
thickness and type. The media recommended by Lexmark
provides the best print quality.
Fuser
Print cartridge
Carousel
First transfer point
Second transfer point
Second transfer roller