Heater Lamp; Fuser Roller; Pressure Roller; Separation Fingers - Toshiba e-STUDIO206L Service Manual

3.15.2

Functions

1. Heater lamp

The heater lamps are halogen lamps to apply heat to the fuser roller. The fuser unit in this
equipment has 3 heater lamps with different functions each other.
3 heater lamps having different functions are called the center heater lamp, the side heater lamp
and the sub heater lamp. The center heater lamp has a coil wound up on its center and this part
generates heat. The side heater lamp has coils wound up on its both ends and these parts generate
heat. The sub heater lamp has a coil wound up in whole and generates heat to assist the center
heater lamp and the side heater lamp.
For e-STUDIO206L/256/306 / 207L/257/307, the sub heater lamp is not installed.
The following is the output of each heater lamp.
Center heater lamp: 600W
Side heater lamp: 600W
Sub heater lamp: 300W

2. Fuser roller

The fuser roller applies heat onto the paper and is heated by the heater lamps installed inside of the
fuser roller. The heat from this roller fuses toner onto the paper. The fuser roller in this equipment is
a thin roller and the warming-up time is shortened.

3. Pressure roller

The pressure roller is a sponge roller which assures the nip amount of the fuser roller. The pressure
from the spring presses the paper onto the fuser roller to fuse the toner onto the paper efficiently.
The pressure roller is electrical conductive, and to improve the transferability and prevent offset,
positive (+) bias is applied to the pressure roller and the entrance guide. A sponge roller with a lower
hardness is adopted for the pressure roller in this fuser unit to enable envelopes to pass through.
The outside diameter of the pressure roller is ø30(mm) for e-STUDIO206L/256/306 / 207L/257/307
and ø35(mm) for e-STUDIO356/456/506 / 357/457/507.

4. Separation fingers

The separation fingers are installed, five above the pressure roller and five above the fuser roller, in
order to separate the paper adhered on each roller.
5. Center thermistor / Side thermistor
This thermistor detects the temperature of the fuser roller to maintain it in a certain temperature
range between the lower limit causing the poor fusing and the upper limit causing the high
temperature offsetting. When the temperature of the fuser roller is lower than the preset
temperature, it turns ON the power supply to the heater lamps, and when it is higher than the preset
temperature, it cuts off the supply.
The center thermistor detects the temperature of the center part of the fuser roller, and the side
thermistor detects the temperature of one side of fuser roller and control the both sides.
6. Edge thermistor
It detects the temperature abnormality at the both ends of the fuser roller. This area may be
overheated without heat absorption by paper since paper does not pass through this area. This
thermistor is not related to the temperature control of the fuser roller.
7. Thermostat
The thermostat cuts off the power supply to the heater lamps by opening itself if the fuser roller
becomes abnormally hot as a result of the problem such as thermistor malfunction. The thermostat
for this equipment is used to prevent abnormal operation. When the thermostat detects any
abnormality, it must be replaced as well as the other damaged parts in the fuser unit.
8. Exit sensor
The exit sensor detects if the leading edge of the paper or the paper has passed through the fuser
unit. This sensor is also used for the detection of a paper jam in the fuser unit and paper exit section.
© 2011-2014 TOSHIBA TEC CORPORATION All rights reserved e-STUDIO206L/256/306/356/456/506 / 207L/257/307/357/457/507
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OUTLINE OF THE MACHINE
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