Drum Cleaning Stage; Erasing Stage - Brother HL-720 - B/W Laser Printer Service Manual

2.5.5

Drum Cleaning Stage

In the image transfer stage, not all the toner on the photosensitive drum is
transferred onto the paper but some of them remain on the drum. In the drum
cleaning stage, the drum surface is cleaned by the cleaning roller, so that residual
toner on the drum surface is removed away and collected in the cleaning roller
itself. The residual toner in the cleaning roller will be discharged to the drum when
starting or unprinting the toner will be collected by a developing roller and reused
(for further developing).
2.5.6

Erasing Stage

Before the cleaning stage, the drum surface is exposed by the light emitted from
the erase lamp. (LED lamp) This stage prepares the drum to decrease
its surface voltage uniformly, and to receive an uniform change in the primary
changing stage.
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