Service manual
CLEANING/TONER RECYCLE UNIT
2-I-2
2 UNIT EXPLANATION
[3] M14 (Blade) Control
M14 (blade) is a 24V DC driven motor and drives the
cleaning blades. By M14, the cleaning blade contacts
on the drum surface slight pressing or pressing to
clean the drum surface. These two blades are auto-
matically switched by M14. M14 is controlled directly
by PRCB (printer control board). Related signals are
PS30 (blade 1) and PS31 (blade 2).
1. Operation
M14 turns ON/OFF in synchronized with ON/
OFF of M2 (drum).
The blade is controlled (pressing, slight pressing,
and switching) by PS30 and PS31 detecting the
blade position, and M14 rotating forward and
backward.
The following table shows the relationship
between PS30/PS31 and blade position.
*Note: CW/CCW indicate the M14 rotating direc-
tion for pressing, slight pressing, and
switching. The sensor logic for slight
pressing position is different between CW
and CCW rotation.
CCW: ON
CW: OFF
a. Blade auto switching control
This unit uses two blades with M14 rotating to
automatically replace blades. During automatic
blade replacement, M2 (drum), M3 (developing),
developing bias, guide plate voltage, and PCL
are turned ON, toner is adhered to the drum, and
then the blade cleans it to prevent blade peeling.
<Timing>
a) At the end of job after every 20,000 copies.
*Changeable with 25 mode DIPSW.
b. Blade setting mode
Blade setting mode is available in 36 mode as a
task after blade replacement during mainte-
nance. Blade setting mode adheres toner on
drum as in blade auto replacement control and
then the blade cleans toner to prevent blade
peeling.
c. Black stripe creation control
In order to improve durability of the blade (stabi-
lize load, prevent paper dust crushing), a black
stripe toner is adhered on drum once every five
copies and then cleaned.
*Changeable with 25 mode DIPSW.
2. Signals
a. Input signal
(1) PS30 (PS30 to PRCB)
Blade position detection signal 1.
(2) PS31 (PS31 to PRCB)
Blade position detection signal 2.
b. Output signal
(1) M14 DRIVE 1,2 (PRCB to M14)
M14 drive control signal.
PRCB
PS30
PS31
5VDC
PS30
SGND
PS31
M14
M14 DRIVE 1
M14 DRIVE 2
DCPS1
DCPS2
24VDC
PGND
5VDC
SGND
Sensor
Blade Position
Pressing CW/
CCW
Slight
pressing
CW/
CCW
Switching
PS30
OFF OFF
ON or
OFF*
ON ON
PS31
ON OFF OFF OFF ON
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