HP LaserJet 4 Service Manual - Page 130
Cleaning Stage
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Cleaning Stage During the cleaning stage of the image formation process, the drum's surface is physically cleaned, preparing it to hold an image. During printing, the drum is rotating constantly making several complete rotations per printed page. Before forming the image for a given section of print, a cleaning blade removes toner from the previous rotation of the drum. The excess toner is stored in the toner cartridge where it is prevented from being used in later print jobs. Figure 5-8 Drum Cleaning Station 5-18 Functional Overview
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 |
 |
Cleaning Stage
During the cleaning stage of the image formation process, the
drum
’
s surface is physically cleaned, preparing it to hold an
image. During printing, the drum is rotating constantly making
several complete rotations per printed page. Before forming the
image for a given section of print, a cleaning blade removes toner
from the previous rotation of the drum. The excess toner is stored
in the toner cartridge where it is prevented from being used in
later print jobs.
Figure 5-8
Drum Cleaning Station
5-18 Functional Overview