Ricoh B064 SERIES Service Manual page 870

IMAGE FUSING AND PAPER EXIT
B140 Series
Many changes were made to make sure that the fusing unit can get to the target
operation temperature in 30 seconds or less.
There are three fusing lamps:
• 650 W Fusing Lamp: Applies heat to the center of the hot roller.
• 550 W Fusing Lamp: Applies heat to the ends of the hot roller.
• 280 W Fusing Lamp: Also applies heat to the ends of the hot roller, but only
during the warmup (after the machine is turned on, or when it recovers from the
energy save mode).
NOTE: Only the 650 W and 550 W fusing lamps turn on and off to keep the hot
roller temperature steady at 185°C.
These changes were made to the hot roller and the pressure roller:
• To make the roller surface become hot more quickly, the thickness and diameter
of the hot roller were decreased.
• The pressure roller surface was changed to a bubble-type material. This gives
the correct nip width between the hot roller and the pressure roller.
The center and end thermistors touch the hot roller. They monitor the temperature
of the hot roller and give feedback for fusing-temperature control.
The thermistor at the center of the hot roller makes temperature detection better.
But its service life is shorter because it always touches the hot roller. For more, see
section "2. Preventive Maintenance".
The three thermostats also monitor the temperature of the hot roller, to prevent
overheating. These thermostats do not touch the hot roller.
Both Series
The web cleaning unit (web roller, cleaning roller, and take up roller) applies a light
coat of silicone oil to the hot roller to prevent toner and paper dust from sticking to
the hot roller.
The fusing exit sensor detects concertina jams at the fusing unit exit. This sensor is
required because the user may not see this type of jam in the machine when
removing a jam at the exit.
The fusing unit and exit unit can be separated, making it easier to service.
B064 Series/B140 Series
/B246 Series/D052 Series
CÓPIA NÃO CONTROLADA
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CÓPIA NÃO CONTROLADA
SM