Epson AcuLaser C8500, Руководство по обслуживанию

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EPSON AcuLaser C8500 Revision C
Operating Principles 2-34
2.5.8 IBT I
TRANSFER ASSY
The TRANSFER ASSY consists of the following parts.
„
1ST BTR
„
BACK UP ROLL
„
CONTACT ROLL
„
IBT DRIVE ROLL ASSY
„
TR0 SENSOR
„
IBT BELT ASSY
†
The 1ST BTR (First Bias Roll) is a conductive roll that sandwiches the IBT
BELT ASSY together with drum, and transfers the toner image on the drum
to the surface of the IBT BELT ASSY (primary transfer).
†
The CONTACT ROLL is metal roll of small diameter that makes contact
with the BACK UP ROLL, and supplies transfer voltage to the BACK UP
ROLL for secondary transfer.
†
The BACK UP ROLL is a conductive roll that sandwiches the IBT BELT
ASSY together with 2ND BTR from the inside, and induces a charge to the
2ND BTR for secondary transfer.
†
The IBT DRIVE ROLL ASSY transmits the drive of the PROCESS MOTOR
ASSY to the IBT BELT ASSY.
†
The positions of the each color toner image transferred must line up
accurately on the IBT BELT ASSY. A silver mark (TRO mark) is therefore
applied to the rear edge of the IBT BELT ASSY as a reference for transfer
position of toner images. The TRO SENSOR detects the transfer reference
mark once per cycle of the IBT BELT ASSY. A TRO signal (signal for
reference point for forming YMCBk image and transfer reference point)
when a certain amount of time elapses following a detection signal.
For B/W Mode (TRO-less mode), without using TRO signal, where the
DRUM and the DEVELOPER ASSY meet is the reference point and a print
control is conducted.
†
The IBT BELT ASSY transfers a toner image of each color developed on
the drum to the IST BTR, forming a complete toner image of the 4
overlapped colors. When the 4-color toner image is formed, a supply of
negative voltage is received from the BACK UP ROLL, and a complete
toner image consisting of 4 colors is transferred (secondary transfer) to
paper.
Figure 2-40. IBT I