Ricoh B234 Service Manual page 908

FUSING
6.16 FUSING
6.16.1 OVERVIEW
[F]
After transferring the image, the copy paper enters the fusing unit. A heat and
pressure process using a hot roller [A] and a pressure roller [B] fuses the image to
the copy paper. There are three fusing lamps of different wattage [C] inside the hot
roller. They are turned on and off to maintain the target fusing temperature.
( 6.16.4)
The CPU monitors the hot roller surface temperature through a thermistor [D],
which is in contact with the hot roller surface. Four thermostats [E] protect the
fusing unit from overheating.
The fusing exit sensor [F] monitors the progress of the copy paper through the
fusing unit and also detects paper jams while the exit rollers drive the copy paper to
the inverter section.
The oil supply roller and cleaning fabric [G] applies a light coat of silicone oil to the
hot roller. It also removes the paper dust and toner from the hot roller.
The hot roller and pressure roller have stripper pawls
jams.
The pressure roller is cleaned by a steel cleaning roller [H]. Toner adheres to steel
more readily than to silicone rubber.
B234/B235/B236/D101/D102/D103
[E]
[H]
6-146
[D]
[A]
B234D501.WMF
, to prevent wrap-around
[G]
[C]
[B]
SM