Fixing (Step 7) - Canon GP215 Service Manual

I. Fixing (step 7)
Main thermistor (TH1)
Sub thermistor (TH2)
Fixing heater
Fixing
Lower fixing roller
cleaning roller
Figure 2-114
After transfer, the copy paper is moved through
the fixing film and the lower fixing roller so that the
toner image will be fused into the fibers 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 moni-
tored by the main thermistor (TH1) located at the
center of the heater. (The fixing heater is con-
trolled 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 aluminum
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.
COPYRIGHT © 1996 CANON INC.
Fixing film
Toner
Copy paper
CANON GP215/200 REV.0 JULY 1996 PRINTED IN JAPAN (IMPRIME AU JAPON)
J. Drum Cleaning
Blade
Figure 2-115
The toner remaining on the drum surface is
scraped by the cleaning blade in preparation for
the next copy. When scraped off the drum surface,
the toner is collected by the scoop-up sheet and
is forwarded to the rear by the blade.
2. COPYING PROCESS
Cleaning blade
Scoop-up sheet
2–7