HP 4300 Service Manual - Page 145

Cleaning the transfer charging roller and photosensitive drum, drum

Page 145 highlights

Cleaning the transfer charging roller and photosensitive drum Residual (left over) toner is cleaned off of the transfer charging roller and photosensitive drum so that subsequent images are crisp and clear. Because not all of the toner is attracted to the media when the image is transferred from the drum, some toner remains on the drum. Toner may also remain on the transfer roller if a jam occurs and the transfer of toner to the media operation is not completed. A dc negative bias (charge) is applied to the transfer charging roller opposite the photosensitive drum, which causes the residual toner to be attracted to the drum. A cleaning blade is in contact with the surface of the drum at all times. As the drum rotates during printing, excess toner from the transfer charging roller and drum are scraped off and stored in the waste-toner receptacle. Cleaning the transfer charging roller Transfer charging roller Residual toner Cleaning the photosensitive drum Waste toner compartment Figure 56. Cleaning blade Cleaning the transfer charging roller and photosensitive drum Q2431-90912 Chapter 5 Theory of operation 125

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Q2431-90912
Chapter 5 Theory of operation
125
Cleaning the transfer charging roller and photosensitive drum
Residual (left over) toner is cleaned off of the transfer charging roller and photosensitive drum so
that subsequent images are crisp and clear. Because not all of the toner is attracted to the media
when the image is transferred from the drum, some toner remains on the drum. Toner may also
remain on the transfer roller if a jam occurs and the transfer of toner to the media operation is not
completed.
A dc negative bias (charge) is applied to the transfer charging roller opposite the photosensitive
drum, which causes the residual toner to be attracted to the drum.
A cleaning blade is in contact with the surface of the drum at all times. As the drum rotates during
printing, excess toner from the transfer charging roller and drum are scraped off and stored in
the waste-toner receptacle.
Figure 56.
Cleaning the transfer charging roller and photosensitive drum
Cleaning the transfer charging roller
Cleaning the photosensitive drum
Residual toner
Cleaning blade
Transfer charging roller
Waste toner compartment