Second Paper Feed Unit (Optional Lower Cassette)
This unit contains no drive motor, so the main motor (M1) drive is transmitted to the paper take-up
and transport sections in the unit via the drive transmission gear. Although the feeding method is
the same as for the paper feed tray in the printer, this unit uses a corner separation system as its
paper separating function. The paper take-up solenoid in the lower cassette is controlled by the
printer via a circuit board in the optional unit.
When the paper regulation plate is set to the inside position, switch S1 on the circuit board is
automatically turned on, causing the printer to recognize that B5-size paper will be fed. On the other
hand, when the paper regulation plate is set to the outside position, S1 remains off, causing the
printer to recognize that A4-size paper will be fed.
2.1.1.2 Drum Charge
The PC drum is charged with static electricity before laser exposure. The r otat ing charge brush and
pre-film are used as the charging method. Less ozone is generated by the corona charge of the
rotating charge brush and the pre-film, and the PC drum can be charged with low voltage because
the charge is dirctly applied to the PC drum. The rotating charge brush is rotated by the drive of the
M1 main motor via its gear.
PWB-A
Paper Empty Sensor (P|1)
Paper Regulation
Plate
Paper Take-Up Roller
Paper Take-Up Clutch
Drive Transmission
Gear
Paper Lift-Up Plate
Transport Roller
Corner Separation
Plate
Paper Take-Up
Solenoid
Figure 2-4. Paper Feeding from the Lower Paper CassetteDrum Cartridge
Rotating Charge
Brush
PC Drum
Protecting
Shutter
PC Drum
Charged Surface:
(approx. -800 V)
PC Drum
Protecting
Shutter
Drum Charging
and Pre-film Bias PWB-F
C169 MAIN-B
A
B Pre-film
A: Drum Charging Bias
B: Drum Ground
IC201
Figure 2-5. Drum ChargeOperating Principles EPL-5500 Service Manual
2-4 Rev. B