Service manual

DRUM UNIT
2-E-2
2 UNIT EXPLANATION
[3] Separation Claw Control
The separation claw is driven by SD4 (separation
claw). The vibration of the separation claw is put in by
M2 (drum). SD4 is controlled directly by PRCB (printer
control board).
1. Operation
a. Separation claw ON/OFF control
SD4 is a pull-type solenoid powered by 24 VDC.
It turns ON to press separation claws against the
drum to help image copied paper separate.
(1) SD4 operation timing
SD4 turns ON after a lapse of specified time from
turning ON of PS45 (leading edge detection) in
the second paper feed section. It turns OFF after
a lapse of the time set by the PRCB timer.
b. Separation claw swing control
Separation claws are swung by M2 (drum) via
the cam mechanism.
2. Signals
a. Output signal
(1) SD4 DRIVE (PRCB to SD4)
SD4 drive control signal.
[L]: SD4 ON
[H]:SD4 OFF
[4] Paper Guide Plate Control
To prevent toner from adhering to the paper guide
plate, a constant voltage is applied to the paper guide
plate. This voltage is supplied from HV2 (high voltage
unit 2) and is controlled by the serial data sent from the
PRCB (printer control board) via the ADUSDB (ADU
stand drive board). When the front door of this machine
opens or closes, MS1 (interlock 1) or MS2 (interlock 2)
operates to interrupt the DC power supply to HV2,
stopping the voltage application to the paper guide
plate.
1. Operation
a. ON/OFF timing
Turning ON/OFF in sync with M2 (drum)
b. Applied voltage
-500 VDC
2. Signal
a. Output signal
(1) GP CONT (ADUSDB to HV2)
This signal controls turning ON/OFF the voltage
application to paper guide plate.
[L]: Voltage applied
[H]:Voltage not applied
24VDC
SD4 DRIVE
24VDC
PGND
M2CONT
M2EM
DCPS2
PRCB
M2
MS2 MS1
SD4
GP CONT
GP
ADUSDB
24VDC
PGND
DCPS2
PRCB
HV2
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