Panasonic DF-1100 Service Manual page 207

System Description
Fusing and Paper Exit
Fuser Unit (431)
The Fuser Unit, consisting of the Fuser Lamp, Fuser Roller, Pressure Roller, Thermistor, and Thermostat,
bonds the toner into the paper using heat and pressure.
Fuser Lamp (408)
Located in the Fuser Roller is a Halogen lamp that serves as the heat source for the Fuser Roller.
Fuser Roller (414)
A Teflon coated roller supplies the heat for bonding the toner to the paper. The temperature of the surface
is kept constant at approximately 190 C ( 10 C) (or 374 F).
Pressure Roller (409)
This converted PFA tube Silicon Rubber Roller applies pressure to the Fuser Roller, assisting in bonding the
toner to the paper.
Thermistor Assembly (405)
The Thermistor, a heat sensitive resistor, in contact with the Fuser Roller, monitors the surface temperature.
The temperature detected is used to control the ON/OFF switching of the Fuser Lamp. It also acts as the
primary overheat prevention device. A comparator circuit on the FCB PC Board acts as a secondary
overheat protection and becomes active at approximately 200 C (392 F).
Thermostat
A Thermostatic Fuse, part of the power line for the Fuser Lamp, provides an extra overheat protection by
opening when the Fuser Roller surface temperature reaches 230 C (446 F) and remains there for 1 minute.
If the primary and secondary overheat protection does not halt the rise in temperature, the thermostat opens,
removing power from the Fuser Lamp. When the Thermostat opens, it must be replaced.
Paper Exit Sensor (610)
This sensor detects the presence of printed paper at the exit. If no paper passes, or if paper is over the sensor
too long, a "RECORDING PAPER JAM" message is displayed. When paper passes over the sensor, the
output is Low (Low Active).
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