Canon PC300 Service Manual page 63

OPERATIONS AND TIMING
©. Fixing/Delivery Assembly
i. Ouiline
The pressure roller in the fixing assem-
bly is driven by the main motor (M1).
The rotation of the pressure roller caus-
es the fixing film to rotate.
Some sections of the underside of the
fixing film is heated by the fixing heater.
The temperature of the fixing heater is
monitored by the thermistor (TH1), and the
readings are sent to the microprocessor on
the DC controller/DC power supply circuit in
the form of the fixing heater temperature
sensor signal (TH1).
Thermal fuse
(228°C) FU2
Fixing heater
Based on the signal, the microprocessor
of the DC controller/DC power supply circuit
controls the temperature of the fixing heater
by the fixing heater drive command (HTRD).
Fixing film
Fixing heater
Pressure roller
Figure 3-31
Relay drive command
(RELAYD)
Fixing heater
overheating |
V sensor circuit
Microprocessor
Figure 3-30
3-36 COPYRIGHT © 1994 1995 CANON INC.
CANON PC300/320/325, FC210/230 REV. FEB. 1995 PRINTED IN JAPAN {IMPRIME AU JAPON)