Fixing Unit System; Overview/Configuration; Outline; Various Control Mechanisms - Canon LBP7200Cdn Service Manual

Chapter 2

2.6 FIXING UNIT SYSTEM

2.6.1 Overview/Configuration

2.6.1.1 Outline

The fixing power supply controls the temperature in the fixing unit. The printer uses an on-demand fixing method.
TH803
Fixing presser roller
- Heater (H801): Heats the fixing film
- Thermistor (T802): Detects the fixing film temperature (Contact type)
- Thermal fuse (FU1): Prevents the fixing heater temperature from rising abnormally high
The thermal fuse is located at the center of the fixing heater.
If the temperature of the fixing heater rises abnormally high, the thermal fuse blows to interrupt power supply to the fixing heater.
These temperature controls in the fixing unit are performed by the fixing control circuit and the fixing heater safety circuit according to the commands from the DC
controller.

2.6.2 Various Control Mechanisms

2.6.2.1 Controlling the Speed of the Fixing Unit

2.6.2.1.1 The speed control of small size paper (throughput down control)

This is a control to prevent the abnormal temperature rising of the fixing heater end side when printing continuously using less than A4 size width paper.
If the paper width is less 210 mm (A4 size) is printed continuously, it adjusts the number of the sheets printed, spread the pickup interval and slow the throughput.
Setting on the driver
Normal paper
Normal paper L
Heavy paper 1
Heavy paper 2
Heavy paper 3
Coat paper 1
Coat paper 2
Coat paper 3
2-14
TH801
FU1
Paper type
Normal paper (75 to 90g/m2)
Thin paper (60 to 74g/m2)
Thick paper (86 to 119g/m2)
Thick paper (120 to 128g/m2)
Thick paper (129 to 163g/m2)
Coat paper (120 to 130g/m2)
Coat paper (155 to 165g/m2)
Coat paper (210 to 220g/m2)
TH802
Fixing
power suplly
Fixing Controll
Fixing Heater
Drive signal
Fixing Temperature signal
F-2-18
T-2-5
Paper size
A4
LTR
LGL
A4
LTR
LGL
A4
LTR
LGL
A4
LTR
LGL
A4
LTR
LGL
A4
LTR
LGL
A4
LTR
LGL
A4
LTR
LGL
DC Contoroller
circuit
Fixing heater
safety circuit
Print speed (ppm)
20.0 < 10.0 < 6.6 < 5.0 < 3.3
21.0 < 10.2 < 6.7 < 5.0 < 3.3
14.1 < 9.2 < 6.3 < 4.7 < 3.2
20.0 < 10.0 < 6.6 < 5.0 < 3.3
21.0 < 10.2 < 6.7 < 5.0 < 3.3
14.1 < 9.2 < 6.3 < 4.7 < 3.2
20.0 < 10.0 < 6.6 < 5.0 < 3.3
21.0 < 10.3 < 6.7 < 5.0 < 3.2
14.1 < 9.2 < 6.3 < 4.7 < 3.2
20.0 < 10.0 < 6.6 < 5.0 < 3.3
21.0 < 10.3 < 6.7 < 5.0 < 3.2
14.1 < 9.2 < 6.3 < 4.7 < 3.2
9.7 < 6.0 < 4.9 < 3.9 < 2.8
9.9 < 6.2 < 5.0 < 4.0 < 2.8
8.3 < 5.4 < 4.5 < 3.7 < 2.7
6.5 < 4.9 < 3.9 < 3.3 < 2.4
6.9 < 5.1 < 4.0 < 3.3 < 2.5
5.6 < 4.3 < 3.6 < 3.0 < 2.3
6.5 < 4.9 < 3.9 < 3.3 < 2.4
6.9 < 5.1 < 4.0 < 3.3 < 2.5
5.6 < 4.3 < 3.6 < 3.0 < 2.3
6.5 < 4.9 < 3.9 < 3.3 < 2.4
6.9 < 5.1 < 4.0 < 3.3 < 2.5
5.6 < 4.3 < 3.6 < 3.0 < 2.3
0021-2021
0021-2047