Service manual

FO-4700U
FO-47UC
3 – 4
7. DRUM CHARGE
The PC Drum is charged with static electricity before laser exposure.
The Rotating Charge Brush and the Precharge-film are used for the
charging method.
The rotating brush charging and the Precharge-film charging generate
little ozone in the printer. Because the charge is directly applied to the
PC Drum, the PC Drum can be charged by low voltage. At the same
time, PC Drum can be charged stably and evenly.
The Precharge-film supplies the charge to the Rotating Charge Brush to
improve the charging efficiency.
The Rotating Charge Brush is turned by the drive of the Printer Motor
(M1) via a gear.
5. PAPER PATH
Paper can be fed into the printer from the Multi Purpose Tray (250 sheets)
or from the Manual Feed Port (1 sheet).
Installing the Paper Cassette Unit (500sheets) adds another feeding
method.
The paper fed by the Paper Take-Up Roller is transported to the Image
Transfer Roller, Fusing Roller and then Paper Exit Roller. After this, the
paper is fed out onto the Print Tray.
Fig. 4
6. PAPER TAKE-UP SECTION
6-1. Multi-Purpose Tray
When the Paper Take-Up Solenoid (SL1) is energized, the drive of the
Printer Motor (M1) is transmitted to the Paper Take-Up Roller via the
Paper Take-Up Clutch (one-way clutch) to turn the Paper Take-Up Roller
one revolution. At the same time, the Depressing Cam turns and lifts the
Paper Tray to feed the top (first) sheet of paper.
The Fixed Separating Pad is used for the paper separation system. It
prevents the second or later sheets of paper from being fed together
with the top sheet.
The printer has no paper size detecting mechanism. It recognizes the
paper size by the paper length which is calculated by the Paper Take-Up
Sensor (PS1) activation timing. Therefore, paper having different widths
are recognized as the same paper size if they have the same length
Fig. 5
Fig. 6
Print Head
Unit
Exposure
Print Exit
Image
Transfer
Fusing
PC Drum
Development
Drum
Cartridge
Toner Cartridge
2nd Transport Unit
Paper Take-up
Sensor (PS1)
Paper Take-up
Clutch
Paper Take-up Solenoid (SL1)
Paper Take-up Roller
Depressing Cam
Paper Empty
Sensor (PE1)
Tray Lifting Plate
Paper Tray
Drum Cartridge
Rotating Charge Brush
Laser Exposure
Sleeve Roller
PC Surface Polisher
Paper Dust Remover
Pre-charge Film
Image Transfer Roller
PC Drum
charged surface:
approx. -800V
Drum Cover