OKIDATA OKIPAGE 20, Service Manual

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transfer roller and the paper. As a results, toner charged negative that is attracted to the image drum
surface is transferred to the upper side of the paper by the positive charge on the lower side of the paper.
(7) Fusing
After the end of the transfer, the unfused toner image is fused on the paper under heat and pressure as it
passes between the heater roller and the back-up roller. The heater roller with a Teflon coating
incorporates a 750W heater (Halogen lamp), which heats the heat roller.
A thermistor which is in contact with the heater roller regulates the heater roller at a predetermined
temperature (about 180 ~ 200°C). A safety thermostat cuts off voltage supply to the heater by opening the
thermostat in the event of abnormal temperature rises.
The back-up roller is held under a pressure of 5 kg from the pressure spring at each side.
(8) Cleaning
After the end of the transfer, residual toner on the image drum is attracted to the cleaning roller temporarily
by static electricity to clean the image drum surface.