Heat Roll - Lexmark T650n Service Manual

4062-XXX

Heat roll

The heat roll is a hollow metal tube with a coated surface. This tube is heated by the inner heater lamp. The
heat is applied to the media passing between the heat roll and pressure roll, fusing the toner on the media.
Pressure roll
The pressure roll is used to apply pressure to the media surface for fusing. Pressure is applied to the media
between the pressure roll and heat roll, pressing the melted toner against the media.
Heater lamp
The heater lamp is a quartz glass tube containing a heater coil. A terminal is mounted to the end of the heater
rod via a harness.
Thermal cutoff
If the heat roll temperature exceeds the preset temperature, the thermal cutoff cuts off the circuits of the main
heater lamp and sub heater lamp.
Thermistor
The thermistor monitors the surface temperature of the media-feed portion of the heat roll to control on/off of
the main heater lamp and sub heater lamp.
Sensor (fuser output)
The sensor (fuser output) detects the arrival of media at the detection point in the exit area of the fuser, and
also detects the ejection of media from this point.
Sensor (narrow media)
The sensor (narrow media) detects the arrival of narrow media at the detection point in the exit area of the
fuser, and also detects the ejection of media from this point. It is used to make adjustments to ensure that
narrow media is properly fused.
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Service Manual