Fixing Control Circuit; Small Size Paper Printing Speed Control (Throughput Reduction Control) - Canon LBP6670dn Series Service Manual

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Technology > Fixing System > Fixing control circuit > Small Size Paper Printing Speed Control (Throughput Reduction Control)

Fixing control circuit

The fixing control circuit controls the temperature in the fixing unit. The printer uses an on-
demand fixing method.
The Figure below shows the configuration of the fixing control circuit.
H1
TP1
TH1
FIXNG HEATER CONTROL signal
Fixing heater
DC controller
control circuit
Engine controller
• Fixing heater (H1): Heats the fixing film
• Thermistor (TH1): Detects fixing temperature (Contact type)
• Thermoswitch (TP1):Prevents an abnormal temperature rise of the fixing heater
(Contact type)
These temperature controls in the fixing unit are performed by the fixing heater control circuit
and the fixing heater safety circuit according to the commands from the DC controller.
2 Technology > Fixing System > Fixing control circuit > Small Size Paper Printing Speed Control (Throughput Reduction Control)
Fixing film
Pressure roller
FIXING TEMPERA TURE signal
Fixing heater
safety circuit
Fixing control circuit
Low-voltage power supply unit
■ Small Size Paper Printing Speed Control (Throughput
Reduction Control)
During continuous printing, the throughput is changed to reduce heat buildup on parts not in
contact with paper, to improve fixing characteristics and reduce curling.
The throughput reduction is implemented according to the following conditions.
Fixing Mode
Envelope 1 – 23 imprints
17 ppm
Envelope 2 1 – 27 imprints
17 ppm
Envelope 3 1 – 31 imprints
12 ppm
Postcard 1 – 31 imprints
12 ppm
16K 1 – 89 imprints
16 ppm
16K Rough 1 – 34 imprints
16 ppm
Long Narrow 1 imprint or more
3 ppm
F-2-14
Throughput
23 – 39 imprints 40 – 47 imprints 48 imprints or more
12 ppm 8 ppm 6 ppm
28 – 62 imprints 63 – 174 imprints 175 imprints or more
12 ppm 8 ppm 6 ppm
32 – 47 imprints 48 – 79 imprints 80 imprints or more
8 ppm 6 ppm 4 ppm
32 – 47 imprints 48 imprints or more
8 ppm 6 ppm
90 imprints or more
14 ppm
35 imprints or more
8 ppm
2-9
T-2-2
2-9