Canon LBP-860, Руководство по обслуживанию

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Reference: Toner projection development
both unexposed and
exposed areas of
the drum surface have a negative potential,
but simplify the explanation, the drum potential is shown as positive when it is higher [less
than the developing cylinder potential, and negative when it is lower (more negative)
than the developing cylinder potential.
Toner and
Description
electrostatic
by the difference in
potential between drum
surface and cylinder is
sufficient to overcome
of the magnet, so
of loner projected depends
the DC bias on
the cylinder.
When the potential dif-
ference between drum
surface and the developing
cylinder is reduced, the
resulting weak electric field
combines with the
to attract toner back
from the drum the
cylinder. This removes any
excessive adhering to
the drum. and improves the
contrast
the
finished
print.
The drum
potential
is only slightly higher than
the cylinder potential, so
to
cylinder is greater than the
electrostatic attraction to
the Therefore, only a
small amount toner is
projected toward the drum.
The
cylinder bias and the
magnetic now
combine to strongly
the toner to cylinder,
removing the excessive
toner from the unexposed
the drum and
preventing fogging.