Fusing-I - Epson ColorPage EPL-C8200 Service Manual

EPSON ColorPage EPL-C8200

2.5.10 Fusing-I

1. Fuser Assembly
The Fuser Assembly fuses the toner on the paper with heat and
pressure, and transfers the paper in and out, to and from the Fuser
Assembly. The Fuser Assembly consists of the Main Fuser
Assembly and the Fuser Tray Assembly.

Main Fuser Assembly
The Main Fuser Assembly consists of the Heat Roll, Pressure
Roll, H/R Heater, P/R Heater, Temperature Sensor Assembly
and others.
• The Heat Roll is a cylindrical metal roll with a rubber layer on
the surface. It applies heat to the paper to fuse the toner onto
the paper.
• The Pressure Roll is a cylindrical metal roll with the rubber
layer on the surface. It applies heat and pressure on the
paper to fuse the toner on the paper.
• The H/R Heater is a halogen lamp in which heating coils have
been sealed. (The heating coils provide the heat source for
the Heat Roll.) The H/R Heater is installed inside the Heat
Roll and heats the Heat Roll to the fusing temperature.
• The P/R Heater is a halogen lamp in which heating coils have
been sealed. (The heating coils provide the heat source for
the Pressure Roll.) The P/R Heater is installed inside the
Pressure Roll and heats the Pressure Roll to the fusing tem-
perature.
• The Temperature Sensor Assembly is a thermistor sensor. It
always touches the Heat Roll and detects the temperature on
the Heat Roll's surface. (A thermistor is an element that
changes its resistance by temperature.) From the detected
temperature, the Temperature Sensor Assembly controls the
ON/OFF of the H/R Heater and P/R Heater and prevents
overheating (primary overheating prevention mechanism).
• The Thermostat is connected (in series) to the power supply
circuits of the H/R Heater and P/R Heater. If the primary over-
heating prevention mechanism of the Temperature Sensor
Chapter 2 Operating Principles
Assembly fails, the contact point in the Thermostat opens,
shutting off the power supply to the H/R Heater and P/R
Heater (secondary overheating prevention mechanism).
• The Thermal Fuse is connected in series to the power supply
circuits of the H/R Heater and P/R Heater. If the primary and
secondary overheating prevention mechanisms fail, the Ther-
mal Fuse is melted by the heat, shutting off the power supply
to the H/R Heater and P/R Heater (tertiary overheating pre-
vention mechanism).
• The Fuser Exit Sensor detects a paper pass from the position
change of the Fuser Exit Actuator.
• The H/R Finger prevents paper from being rolled into the
Heat Roll.
• The P/R Finger prevents paper from being rolled into the
Pressure Roll.
Revision A
2-35