Ricoh FT5034 Service Manual page 77

The PCC prevents this problem. As the region
of the drum with toner still attached moves into
the cleaning unit, the PCC applies a positive
charge, and the charge on the toner is changed
from negative to positive. Since like charges
repel, it is much easier for the cleaning blade to
remove the toner from the drum. Also, since
the cleaning brush is grounded, the fibers of
the brush have a negative charge
electrostatically induced by the positive charge
on the drum. The negatively charged brush
attracts the positively charged toner and
removes about half of it from the drum. This
further reduces the load on the cleaning blade.
3. Drive Mechanism
The main chain drives the cleaning unit when the main motor is on. The brush gear
is fitted into the cleaning drive sprocket. A pin on the inside of the sprocket drives an
Allen screw on the shaft of the gear, turning the gear. The brush gear drives the coil
gear directly, and the toner in the unit is transported to the toner collection bottle by
the toner collection coil.
Brush Gear
Main Chain
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Cleaning Blade
Cleaning
Brush
PCC
Allen Screw
Cleaning Drive
Sprocket
Coil Gear
Cleaning Solenoid
Toner
T/S Corona Unit
Cleaning Brush
Toner
Collection Coil
QL