Lexmark CX310dn, Service Manual

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The HVPS sends voltage to the transfer roll to create a positive charge. When the image on the transfer belt reaches
the transfer roll, the negatively charged toner clings to the paper and the entire image is transferred from the transfer
belt to the paper.
Service tips
• If the transfer roller has nicks, pits, or flat spots on it, the surface doesn’t come into contact with the paper and
transfer unit. This will cause voids or light spots on the page or repeating voids/light areas.
• If the transfer roller does not engage the transfer unit, or does not have voltage coming from the HVPS, the toner
will not fully transfer from the transfer unit; the entire page will be very light or blank. Any toner that does transfer
will be due to a “contact” transfer instead of a “charge” transfer. Check the HVPS contacts to the transfer roller.
Step 5: Fuse
When the image has been fully transferred to the paper, the transfer roll helps move the paper into the fuser area.
The fuser applies heat and pressure to the page to melt the toner particles and bond them permanently to the paper.
The fuser moves the paper to the redrive rolls which move the paper to the output bin.
Service tips
•
If the fuser rollers are damaged, they can cause toner to be pulled off the page or cause paper jams.
•
Toner that rubs off a printed page can be a sign of a malfunctioning fuser or an improper paper setting. Always
check the paper type setting before replacing the fuser. A common mistake is to print on heavier media (such as
cardstock) with the paper type set to plain paper.
• When removing paper jams from the fuser, be sure to use the fuser release tabs to relieve the pressure on the page.
In addition, never pull unfused toner through the fuser if you can help it; try to back the jammed page out of the
fuser in the opposite direction it was travelling.
Step 6: Clean/Erase
There are two main cleaning processes that take place during the EP Process. One process cleans the transfer belt, and
the other cleans the photoconductors.
Transfer unit clean
When the toner image on the transfer belt has been transferred to the page, the transfer belt rotates around and is
cleaned by the cleaning blade (G). This occurs for every page that is printed.
After the toner is moved to the cleaning blade, the toner is moved to the waste toner area using an auger system.
Photoconductor clean/erase
After each plane of color has been transferred to the transfer belt from the photoconductors, a cleaning blade (H)
scrapes the remaining toner from the surface of each photoconductor. This is the clean/erase process.
Now the photoconductor surface is prepared to restart the EP Process. This cleaning/erasing cycle happens after each
plane of color is transferred to the transfer belt.
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Appendix C: Theory of operation
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