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AR-651/810 TRANSFER/TRANSPORT UNIT 13 - 2
13. 3. Functions
(1) Transfer belt unit
The transfer belt is coated with a high-precision flat rubber belt and has electrical resistance. The
transfer belt unit is divided into a belt support/power supply section and a cleaning mechanism. The
belt support/power supply section supports the belt and rotates to supply power, and the cleaning
mechanism scrapes of toner from the belt surface.
(2) Transfer belt support/power supply mechanism
As shown in Figure 1, the transfer belt is supported by 3 rollers (transfer belt drive roller, follower roller
and power supply roller). Voltage having a polarity opposite to that of the toner on the photoconductive
drum is applied to the power supply roller. The current flowing to the transfer belt is controlled to a
constant current of 80µA. (Though the applied voltage changes as current is constant, the voltage
change is normally within the range +2 to +5kV.) +510 voltage is applied to the follower roller by the
varistor. A voltage probe is required for measurement. To prevent danger, do not use a digital voltmeter.
(3) Transfer belt cleaning mechanism
The cleaning mechanism has two functions, a function for scraping off residual toner and paper dust
from the belt surface by the cleaning blade and cleaning brush and transporting the used toner with the
recovery auger, and a function for bringing the transfer belt into contact with and separating from the
drum.
(4) Cleaning blade
After the paper is separated, the cleaning blade removes paper dust and foreign matter remaining on
the belt surface.
(5) Cleaning brush
The cleaning brush is electroconductive for electro-statically cleaning the toner. A voltage opposite to
that of the toner is applied to the toner. The current flowing to the brush is controlled to a constant
current of 5µA. (Though the applied voltage changes as current is constant, the voltage change is
normally within the range +100 to +500V.) A voltage probe is required for measurement. To prevent
danger, do not use a digital voltmeter.
(6) Recovery auger
The recovery auger transports the scraped toner to the used toner transport auger section.
(7) Transport guide
The transport guide guides the paper that is held in contact by static electricity to the fuser unit. It is
made of the material that prevents electrification caused by the friction with the paper.
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