Fuser Unit - Panasonic DX-2000 Service Manual

Beam Detection (BD) Lens and Beam Detection (BD) Sensor
The BD Lens receives the reflected light from the Polygon Mirror and redirects it into the BD Sensor, which converts the laser
beam into electrical signals and sets the start timing for the scanning line.
f-θ lens
This amorphous plastic, molded lens is designed to provide parallel laser light across the surface of the drum, providing a
constant scanning speed.
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).
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