Ricoh B246 SERIES, Manual, Page: 229 / 268

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Transfer Belt Unit
Drum
Transfer Roller Transfer Belt
Transfer Belt
Cleaning Unit
Waste Toner
Collection Coil
Cleaning
Roller
(electrically
charged)
Cleaning
Blade
Transfer Belt
Lift Lever
(operated by a
solenoid)
Service manual, section 6.10.1
ˆ
This model uses a transfer belt.
ˆ
The belt has a high electrical resistance, so that it can hold a high positive voltage
to attract toner from the drum to the paper.
ˆ
The belt has a cleaning roller to remove toner from the belt. This prevents the
backside of copies from getting dirty.
¾
The roller is given a positive charge.
¾
The cleaning roller has its own cleaning mechanism (a counter blade).
¾
The toner collection coil in the transfer belt-cleaning unit sends waste toner to
the collection bottle.
¾
The bottle contains a toner overflow sensor.
¾
This toner is not recycled, because it contains paper dust.
ˆ
A solenoid lifts the belt into contact with the drum at the required time.
ˆ
The transfer belt has the following advantages over a corona wire system:
¾
The belt contacts the full width of the drum to ensure better transfer
¾
Less ozone
¾
More stable paper separation and transportation
A transfer roller is not used in a high cpm machine because the efficiency
of transfer charge is not as high as with a belt.
ˆ
Describe how paper separates from the drum.
¾
Electrostatic attraction and the pick-off pawls both play a part.