AR-155 (serv.man8). AR150 155 ARF151 Service Manual-Operational Descriptions - Sharp Copying Equipment Service Manual (repair manual)

CODE: 00ZARF151/A1E

[ 1 ] GENERAL .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  1  -  1

[ 2 ] SPECIFICATIONS  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  2  -  1

[ 3 ] CONSUMABLE  PARTS  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  3  -  1

[ 4 ] EXTERNAL  VIEWS  AND  INTERNAL  STRUCTURES  .  .  .  4  -  1

[ 5 ] UNPACKING  AND  INSTALLATION  .  .  .  .  .  .  .  .  .  .  .  .  .  5  -  1

[ 6 ] OPERATIONAL  DESCRIPTIONS  .  .  .  .  .  .  .  .  .  .  .  .  .  .  6  -  1

[ 7 ] DISASSEMBLY  AND  ASSEMBLY  .  .  .  .  .  .  .  .  .  .  .  .  .  .  7  -  1

[ 8 ] ADJUSTMENTS  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  8  -  1

[ 9 ] SIMULATION, FAX SOFTWARE SWITCH,

  TROUBLE  CODES  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  9  -  1

[10] USER  PROGRAM  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 10  -  1

[11] ELECTRICAL  SECTION  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 11  -  1

[12] CIRCUIT  DIAGRAM  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 12  -  1

CONTENTS

Parts marked with “  ” are important for maintaining the safety of the set. Be sure to replace these parts with specified
ones for maintaining the safety and performance of the set.

(AR-F151)

AR-F151

The outline of operation is described referring to the basic configuration.

Setting conditions

1) Set copy conditions such as the copy quantity and the copy density with the operation section, and press the COPY button. The information

on copy conditions is sent to the MCU.

Image scanning

2) When the COPY button is pressed, the scanner section starts scanning of images.

The light from the copy lamp is reflected by the document and passed through the lens to the CCD.

Photo signal/Electric signal conversion

3) The image is converted into electrical signals by the CCD circuit and passed to the MCU.

Image process

4) The document image signal sent from the CCD circuit is processed under the revised conditions and sent to the LSU (laser unit) as print data.

Electric signal/Photo signal (laser beam) conversion

5) The LSU emits laser beams according to the print data.

(Electrical signals are converted into photo signals.)

6) The laser beams are radiated through the polygon mirror and various lenses to the OPC drum.

Printing

7) Electrostatic latent images are formed on the OPC drum according to the laser beams, and the latent images are developed to be visible im-

ages (toner images).

8) Meanwhile the paper is fed to the image transfer section in synchronization with the image lead edge.
9) After the transfer of toner images onto the paper, the toner images are fused to the paper by the fusing section. The copied paper is discharged

onto the exit tray.

Operation

section

Scanner section

CCD 

MCU (Main control/image process section)

Laser beam

Paper exit

Fusing section

Paper transport section

Manual paper

feed section

Cassette paper

feed section

Printer section

LSU (Laser unit)
Laser diode, Polygon mirror lens

Process section

AR-F151

6 – 1

The scanner has sensors that are arranged in a line. These sensors scan a
certain area of a document at a time and deliver outputs sequentially. When
the line is finished, the next line is scanned, and this procedure is repeated.
The figure below shows the case where the latter two sections of an image
which are scanned are shown with solid lines and the former two sections
which are being transmitted are shown with dotted lines.
The direction of this line is called “main scanning direction,” and the scanning
direction  “sub scanning direction.”
In the figure above, one line is divided into 4 sections. Actually, however, one
line is divided into thousands of sections. For scanning, the light receiving ele-
ment called CCD is used.
The basic resolution indicates the scanner capacity. The basic resolution is ex-
pressed in dpi (dot/inch) which shows the number of light emitting elements per
inch on the document.
The basic resolution of this machine is 400dpi.
In the sub scanning direction, at the same time, the motor that drives the op-
tical system is controlled to scan the image at the basic resolution.

1

Copy lamp (Xenon lamp)

2

Reflector (light conversion plate)

3

No. 1 mirror

4

No. 2 mirror

5

No. 3 mirror

6

Lens

7

No. 2/3 mirror unit

8

Copy lamp unit

9

CCD

10

Mirror motor

11

MHPS (Mirror home position sensor)

The scanner unit performs scanning in the digital optical system.
The light from the light source (Xenon lamp) is reflected by a document and passed through three mirrors and reduction lenses to the CCD element
(image sensor) where images are formed. This system is known as the reduction image sensor system. Photo energy on the CCD element is con-
verted into electrical signals (analog signals). (Photo-electric conversion). The output signals (analog signals) are converted into digital signals (A/D
conversion) and passed to the MCU (main control/image process section). The resolution at that time is 400dpi.
The mirror unit in the scanner section is driven by the mirror motor.
The MHPS is provided to detect the home position of the copy lamp unit.

(6)

(5)

(4)

(3)

(2)

(1)

(10)

(11)

(9)

(8)

(7)

1

2

3

4

5

5

4

3

2

1

Sub scanning direction

Sensor scanning area

Main 
scanning 
direction

Original

Image data sent to the ICU PWB

To MCU PWB

The image data sent from the MCU (image process circuit) is sent to
the LSU (laser unit), where it is converted into laser beams.

The LSU unit is the writing section of the digital optical system.
The semiconductor laser is used as the light source, and images are
formed on the OPC drum by the polygon mirror and f

θ lens, etc.

The laser beams are passed through the collimator lens, the cylindrical
lens, the polygon mirror, the f

θ lens, and the mirror to form images on

the OPC drum in the main scanning direction. The laser emitting PWB
is provided with the APC (auto power control) in order to eliminate fluc-
tuations in the laser power. The BF PWB works for measurement of the
laser writing start point.

(1)

(2)

(3)

(4)

(5)

 : Laser beam

path for BF PWB

AR-F151

6  –  2

No.

Component

Function

(1)

Semiconductor laser

Generates laser beams.

(2)

Collimator lens

Converges laser beams in
parallel.

(3)

Polygon mirror,
polygon motor

Reflects laser beams at a
constant rpm.

(4)

BD (Mirror, lens,
PWB)

Detects start timing of laser
scanning.

(5)

f

θ lens

Converges laser beams at a
spot on the drum.

Makes the laser scanning
speeds at both ends of the
drum same as each other.
(Refer to the figure below.)

Makes the laser scanning speeds at both ends of the drum same as
each other.

Effective scanning width:

216mm (max.)

Resolution:

600dpi

Beam diameter:

75um in the main scanning
direction, 80um in the sub scanning
direction

Image surface power:

0.20 

±0.03mW (Laser wavelength

780  – 795nm)

Polygon motor section:

Brushless motor 20.787rpm
No. of mirror surfaces: 6 surfaces

General block diagram (cross section)

Top view

(1) Heat roller
A pressure roller is used for the heat roller and a silicone rubber roller
is used for the lower heat roller for better toner fusing performance and
paper separation.

(2) Separator pawl
Three separator pawls are used on the upper heat roller. The separator
pawls are teflon coated to reduce friction with the roller and prevent a
smear on the paper caused by the separator pawl.

a 

≠ b ≠ c

a

b

c

d = e = f

d

e

f

 

f

θ LENS

Heat roller

Thermistor

Thermal fuse

Heater lamp

Separator pawl

Separator pawl

PPD2

Thermal fuse

Thermistor

Heat roller

Paper guide

Pressure roller

AR-F151

6  –  3