Cleaning: Stage One - HP LaserJet II Serie Manual De Instrucciones

HP 33440/HP 33449 COMBINED SERVICE MANUAL
CLEANING: Stage One
During the first stage of the image formation process, the drum's sufice is prepared to hold an
image through a physid and electrid cleaning process. During printing, the drum is constantly
rotating, mting several complete rotitions per printed page. Before forming the image for a given
section of print, lefiover toner from the previous rotation of the drum must be removed. This is
accomplished by a rubber cleaning blade which scrapes toner off the drum and into a debris cavity.
A sweeper blade in the debris cavi~ rotates, weeping toner away from the area near the drum
(see Figure 5-4).
The drum is electrostatidly cleaned by the Erase bmus (see Figure 5-5). These five small lamps,
lomted in the hinged Top Cover Assembly, Muminate the drum's photosensitive material to
neutdlze any electrid charges which may have previously been on the drum. The illumination
of these lamps is controlled by the Machine Control System (DC Contro~er PCA).
Cleaning blade
I
Sweeping
Sweeper strip
Figure
5-4. Drum Cleaning
Station
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Lamps
Red
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Filter
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1
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Photosensitive
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Layer
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Aluminum
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Base
Figure
5-5.
Erase
Lamp Effect
5-6