K. Fixing/Delivery Assembly
1. Outline
The drive roller of the fixing assembly is driven by the main motor (M1).
When the drive roller rotates, the fixing film rotates, thereby rotating the lower fixing roller.
Part of the inner side of the fixing film is heated by the fixing heater.
The temperature of the fixing heater is checked by the thermistor (TH1), and the result is sent to the
microprocessor on the DC controller PCB as the fixing heater temperature detection signal (TH1).
Based on the TH1 signal, the microprocessor on the DC controller PCB varies the fixing heater drive
signal (HTRD) to control the temperature of the fixing heater.
The rear end of the fixing heater is also equipped with a thermistor (TH2) to check for overheating of
the end.
The machine is designed as such that the pressure between the film and the lower roller of the fixing
assembly is released when the front door is opened.
COPYRIGHT © 1996 CANON INC. CANON GP215/200 REV.0 JULY 1996 PRINTED IN JAPAN (IMPRIME AU JAPON)
3–118
3. OPERATIONS AND TIMING
Figure 3-639
24V
5V
5V
5V
5V
5V
5V
A
A
Fixing assembly end
temperature signal (TH2)
Fixing temperature signal (TH1)
Sub thermistor (TH2)
Main thermistor (TH1)
Fixing heater drive circuit
Relay
Composite power
supply PCB
Zero cross signal
SW2
Fixing heater (H4)
DC controller PCB
Relay drive signal
Fixing heater drive signal (HTRD)
CPU
I/O
PWM