DOWNLOAD Sharp AR-285 (serv.man11) Service Manual ↓ Size: 747.22 KB | Pages: 28 in PDF or view online for FREE

1) Remove the screw and the connector which connect the toner

hopper and the developing unit, and separate them. 

2) Loosen the DV doctor fixing screw A.

3) Insert a thickness gauge (0.6mm) into the clearance of 40mm 

∼

 70mm from the DV doctor edge.

4) Press the DV doctor in the arrow direction and tighten the DV

doctor fixing screw. (Perform the same procedure for the front and
the rear frame.)

5) Check that the clearance (2 positions) at 40mm 

∼

 70mm from the

both ends is 0.6 

±

 0.03mm. 

When inserting a thickness gauge, be careful not to scratch the
DV doctor and the MG roller. 

1) Remove the screw and the connector which connect the toner

hopper and the developing unit, and separate them. Put the devel-
oping unit on a flat floor. 

2) Tie a needle or pin on a string. 

3) Hold the string and put the needle horizontally and move it toward

the MG roller. (Do not use a clip which is too big to have a correct
position since the MG roller diameter is small.)

4) With the needle tip at 2 

∼

 3 mm apart from the MG roller surface,

mark the point on the surface which is on the extended line of the
needle tip. 

5) Measure the distance between the marking position and surface P

of the developing unit and check that it is 17mm.

If the distance is not as specified above, loosen the fixing screw A
of the main pole adjustment plate, and move the adjustment plate
to adjust. 

P

7 – 2

1) Set the digital multi-meter range to the DCV range. 

2) Put the test rod between the DV bias output check pin (CN2-1 pin)

of the high voltage unit and the chassis (GND).

3) Execute SIM 8-1.

The DV bias can be measured without installing the OPC drum
and the developing unit. 

4) When the output voltage is within the adjustment range, change

the displayed value and adjust. (1 step: about 1 V)

Adjustment range

Developing negative bias voltage (Auto)

–500 

±

5V

Developing negative bias voltage
(Character)

–500 

±

5V

Developing negative bias voltage
(Character, Photo)

–500 

±

5V

Developing negative bias voltage (Photo)

–500 

±

5V

Developing negative bias voltage (FAX)

–500 

±

5V

Developing bias (Printer)

–500 

±

5V

Developing positive bias voltage

+150 

±

5V

(The value and the output voltage may not coincide.)

1) Install the DV unit, the drum holder unit, and the charger units to

the copier. 

2) Turn on the main switch, and execute SIM 8-2 to check the grid

voltage set value. 

(Measurement at the high voltage PWB check point)

3) Remove the rear cabinet. 

4) Connect the digital multi-meter to the grid voltage output check pin

(CN2-5 pin).

5) Set the digital multi-meter range to the DCV range.

(Use a digital multi-meter which allows measurement up to
DC1000 V.)

6) Manually turn on the door switch. 

7) Turn on the main switch, and execute SIM 8-2 to check. 

8) If the output voltage is not in the specified range, change the

displayed value and adjust. (1 step: about 1V)

Adjustment range

Grid voltage (Auto)

–642 

±

5V

Grid voltage (Character)

–642 

±

5V

Grid voltage (Character, Photo)

–642 

±

5V

Grid voltage (Photo)

–642 

±

5V

Grid voltage (Printer)

–642 

±

5V

Grid voltage (FAX)

–642 

±

5V

(The value and the output may not coincide.)

7 – 3

1) Remove the developing unit, the transfer/separation charger unit,

and the main charger unit from the copier. 

2) Remove the process unit from the copier. 

3) Remove the OPC drum from the process unit, and install the

electrode sheet by using a ring rubber, tape, etc. 

4) Install the OPC drum with the electrode sheet installed to the

process unit, and install the process unit to the copier. 

5) Install the drum holder unit to the copier so that the electrode

sheet lead wire can be taken out from the developing unit side.

6) Clean the transfer charger wire and install the transfer/separation

charger unit to the copier.

(Do not install the main charger unit.)

7) Connect the electrode sheet and the digital multi-meter (or an

ammeter). Manually turn on the door switch.

8) Check the drum current on the front frame side and the rear frame

side.

The current on the front and the rear frame sides: within 6.0uA

•

Turn on the main switch, and execute SIM 8-6.

(THVG will be turned ON for about 30 sec.)

•

Measure the drum current on the front frame side and the rear
frame side.

•

When the microswitch is OFF, the drum current on the front
frame side is displayed.

•

When the microswitch is ON, the drum current on the rear
frame side is displayed.

•

Check that the current on the front and the rear frame side is
6.0

µ

A or less.

If the current is greater than 0.6

µ

A, replace the charger unit

with new one.

9) Adjust THVG output current.

•

Turn on the main switch and execute SIM 8-6.

UKOG-0110FCZZ

UK0G

-0110FCZZ

A

(QCLIZ0005FCZZ)

(QCLIZ0006FCZZ)

(QCLIZ0010FCZZ)

(QCLIZ0004FCZZ)

(QCLIZ0002FCZZ)

PHOG-0007FCZZ

QTIPH0017FCZZ

(VRN-RT2EK304F)

300K

Ω

 X 2

Electrode sheet (UKOG-0110FCZZ)

Electrode sheet harness (DHAI-0304FCZZ)

Orange

Orange

Blue

White

Black

White

Red

(Parts arrangement)

Orange

White

Blue

Black

(Microswitch)

(QSW-M0118FCZZ)

Green

Blue

Black

Yellow

Red

N/C

N/O COM

(OFF)

N/C

N/O COM

(ON)

7 – 4

(THVG will be turned on for about 30 sec.)

•

If the output current is not in the specified range, change the
displayed value and adjust. (1 step: about 0.1 

µ

A)

Transfer charger current

Adjustment spec

TC drum current (Front surface mode)

+

13.5

−

0

+

1.5

µ

A

TC drum current (Back surface mode)

+

13.5

−

0

+

1.5

µ

A

Check that the black clip is securely grounded to the machine
chassis. 

When UKOGE0043CS01 is used:

Knob 1:

Set to DCmA.

Knob 1:

Connect to 2. 

Red clip: Connect to (+).
Blue clip: Connect to (–).

When an ammeter is used:

Red clip: Connect to (+) of the ammeter.
Blue clip: Connect to (–) of the ammeter.

1) Install the DV unit, the drum holder unit, and the charger units to

the copier.

2) Remove the rear cabinet. 

3) Connect the digital multi-meter to SHVG output check pin (CN2-3

pin). 

4) Set the digital multi-meter range to the DCV range. 

5) Manually turn on the door switch. 

6) Execute SIM 8-7. (SHVG will be turned on for about 30 sec.)

7) If the output voltage is not in the specified range, change the

displayed value and adjust. (1 step: about 1V)

Adjustment range

Separation DC component voltage (Front
surface mode)

–140 

±

10V

Separation DC component voltage (Back
surface mode)

–140 

±

10V

This adjustment must be performed in the following cases:

•

When both sensors are cleaned in maintenance.

•

When the value of DMLED/PCLED in SIM 44-12 are greater than
about 100.
Clean both sensors and perform the adjustment.

1) Execute SIM 44-2.

2) When the adjustment is completed, the gain value is displayed. If

an error occurs during the adjustment, the error display is made.

This adjustment must be performed in the following case:

•

When new developer is supplied.

1) Execute SIM 25-2.

2) The adjustment is automatically made with the toner density sen-

sor output value displayed. After 3 minutes from starting stirring,
the toner density sensor is sampled 16 times, and the average
value is stored as the toner density adjustment value. 

When new developer is supplied, clear the developer counter
with SIM 24-5.

2

20

200

(DCmA)

F

R

Green grip

Yellow grip

Black grip

Body chassis
(no coating)

Black

Blue

Red

White

Orange

Orange

Microswitch

Blue grip

Red grip

Digital multi-meter
(UKOGE0043FC01)

White

7 – 5