Toshiba e-STUDIO2500c, Service Manual, Page: 329 / 402

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May 2006 © TOSHIBA TEC e-STUDIO2500c/3500c/3510c FUSER UNIT / PAPER EXIT SECTION
15 - 5
15.4 Description of Operation
The fuser belt is located between the fuser roller and pressure roller. The fuser roller is pressed with the
spring force from the pressure roller side, and it is rotated by the fuser motor (M17) drive. The fuser belt
also rotates simultaneously. Then the paper transported to the fuser unit is hold between the fuser belt
and pressure roller and the toner is fused on the paper with heat and pressure. After this, the separation
fingers and separation plate separate the paper from the fuser belt. Then the paper is transported to the
inner tray, paper exiting options or ADU through the exit roller.
The fuser unit of the equipment has 2 heater lamps (center heater lamp / side heater lamp) installed in
the heat roller and 1 (pressure roller lamp) in the pressure roller.
The pressure roller lamp is turned ON/OFF constantly to maintain the preset temperature in order to
stabilize the surface temperature of the pressure roller, reduce warming up time and enhance fusing
ability.
The heat roller center thermopile (THMP1) and heat roller rear thermopile (THMP2) control the temper-
ature of heat roller and the heat roller center thermostat (THMO1) and heat roller rear thermostat
(THMO2) detect the temperature abnormalities of heat roller. If the temperature becomes excessively
high, the heat roller front thermistor (THM3) is opened to stop the power supply to the center and side
heater lamps (LAMP1 / LAMP2).
Also, the pressure roller center thermistor (THM4) and pressure roller rear thermistor (THM5) control
the temperature of pressure roller. If the temperature becomes excessively high, the pressure roller
thermostat (THMO3) is opened to stop the power supply to the pressure roller lamp (LAMP3).
When transporting OHP film or thick paper, the transport speed is reduced by 1/2 of the normal one in
order to improve fusing efficiency.