Controlling The Fixing Temperature - Canon NP6045 Service Manual

C. Controlling the Fixing Temperature
The surface temperature of the upper fixing roller is monitored by the main thermistor
(TH1), and the output of the thermistor is sent to the microprocessor.
Using the output, the microprocessor varies the main heater drive signal (MHRD)
and the sub heater drive signal (SHRD) to control the fixing temperature.
The rear of the copier's upper fixing roller is equipped with a sub thermistor (TH2) to
monitor overheating.
PS47
COPYRIGHT © 1997 CANON INC.
DC controller PCB
Cleaning belt
guide plate
Upper fixing
roller
PS52
Figure 6-102
CANON NP6045 REV. 1 MAR. 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 6 FIXING SYSTEM
PS11
Sub
thermistor
(TH2)
Main thermistor (TH1)
TPI
Thermal
switch
AC power supply
Lower
fixing
roller
SSR
AC driver PCB
6-3