Fusing The Copies And Output Of The Copies - Oce 3121 Technical & Service Manual

2 Fusing the copies and output of the copies

Outline
Motor M1 rotates the drive roller of the fuser. The drive roller turns the fusing
film which, in turn, rotates the lower roller.
The inside of the fusing film is heated by the heater. The temperature of the
heater is monitored by the thermistor TH1. The heater temperature detection
signal TH1 is transmitted to the DC control PBA. As a result, the DC control
PBA varies the heater drive signal HTRD to control the temperature of the
heater.
A thermistor TH2 is located at the rear end of the heater. This is to protect
against over-heating.
If the front door is opened, there is a reduction of pressure between the fuser
film and the lower roller.
502 TSM Océ 3121
Fixing assembly end
temperature signal (TH2)
Sub thermistor (TH2)
Fixing temperature signal (TH1)
Main thermistor (TH1)
Fixing heater drive circuit
Relay
Zero cross signal
Composite power
supply PCB
5V
5V
5V
5V
5V
5V
24V
Relay drive signal
Fixing heater drive signal (HTRD)
A
DC controller PCB
CPU
A
I/O
PWM
Functional description