Lexmark X500n Service Manual page 126

7100-XXX
Transfer unit cleaning
Once the toner image on the transfer unit has been transferred to the page, the transfer unit rotates
around and is cleaned by the cleaning roller. This cleaning happens after each page is printed.
A clutch engages a cam to lower the cleaning brush on the surface of the transfer unit and another
clutch rotates the brush. The high voltage power supply sends a charge to the cleaning brush so the
toner will want to stick to the cleaning brush instead of the transfer unit surface.
The waste toner is kicked into a containment area and moved by an auger system into the waste toner
bottle. This is the transfer unit clean process.
Look at callout 6 in the picture below. This is the where the transfer unit is cleaned by the cleaning
roller.
Note: If the cleaning roller is not positioned properly, it will not contact the transfer unit surface
correctly. This results in waste toner remaining on the transfer unit and will cause residual images or
"ghost" images. in other words, the remaining toner from one page will carry over to the next page as a
light "ghosted" image on the printed page.
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Service Manual
Lexmark confidential until announce edited 1/4/2007