Oce 3121, Technical & Service Manual

Page: 198 / 908

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ed.1 General operation 9
Fusing
After separation, the copy paper is passed between the fusing film and the fuser
roller. The toner image is fused to the fibres of the paper.
The fixing heater is a plane-shaped heater; it serves to eliminate warm-up time
by heating the area of contact with the fixing film.
The temperature of the fixing heater is monitored by the main thermistor (TH1)
located at the centre of the heater. (The fixing heater is controlled to a specific
temperature at all times.)
A sub thermistor (TH2) is provided at the end of the fixing heater to monitor
the temperature of the area which remains free of contact with paper when
small-size paper is moved through the fixing assembly, thereby preventing
overheating.
The fixing cleaning roller is made of aluminium and is kept in contact with the
lower fixing roller to remove toner from the lower fixing roller. (It also serves
to discharge heat from the lower fixing roller.)
The metal core of the lower fixing assembly is given a positive bias to prevent
offset of toner to the fixing film.
OPC cleaning
The remaining toner on the OPC is scraped off by the cleaning blade. This as
a preparation for the next copy. The toner that is scraped off is caught by a me-
linex strip, and moved to the waste container by a rotary blade.
Main thermistor (TH1)
Sub thermistor (TH2)
Fixing film
Fixing heater
Fixing
cleaning roller
Lower fixing roller
Toner
Copy paper
main thermistor (TH1)
sub thermistor (TH2)
fixing film
toner
copy paper
lower fixing roller
fixing cleaning
roller
fixing heater
Cleaning blade
Blade
Scoop-up sheet
cleaning blade
blade scoop-up sheet