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AR-C172M  SETTING AND ADJUSTMENTS  8 - 16

6) With the scanner unit B in contact with the both stoppers on

the CCD mounting plate at the same time, fit the edge of the
scanner unit A with the frame right edge and fix the scanner
unit A with the screw.

1) Make a test chart on A3 (11" x 17") paper as shown below.

(Draw a rectangular with four right angles.)

2) Set the test chart made in procedure 1) on the document

table. (Leave a space of about 30mm between the reference
position and the test chart.) With the document cover open,
make a copy on A3 (11" x 17").

3) Check for distortion in the sub scanning direction.

If La = Lb, there is no distortion.

If there is some distortion in the sub scanning direction, perform
the following procedures.

4) Loosen either of two fixing screws of the scanner unit drive

pulley. (Either one on the front or the rear side will do.)

5) With the scanner unit drive shaft kept stationary, turn the scan-

ner unit drive pulley manually to change the parallelism of
scanner units A and B. (Change the relative positions of the
scanner unit drive pulley and the drive shaft.)

6) Tighten the scanner unit drive pulley fixing screw.

Repeat procedures 2) – 6) until the condition of procedure 3)
is satisfied.

If the distortion in the sub scanning direction cannot be deleted
with the above procedures, perform ADJ 6D, Scan image distor-
tion adjustment.

L

L

L

L

L = 10mm

Lb

La

AR-C172M  SETTING AND ADJUSTMENTS  8 - 17

1) Make a test chart on A3 (11" x 17") paper as shown below.

(Draw a rectangle with four right angles.)

2) Set the test chart made in procedure 1) on the document

table. With the document cover open, make a copy on A3 (11"
x 17").

3) Check for distortion in the main scanning direction.

If the four angles of the rectangle on the copy are right angles,
there is no distortion. (Completion of the adjustment)

If there is some distortion in the main scanning direction, perform
the following procedures

4) Check the difference (distortion balance) of left and right

images distortions.

If Lc = Ld, the distortion on the left is equal to that on the right.
(The distortions are balanced.)

If the above condition is satisfied, go to procedure 6).

If the above condition is not satisfied, perform the following proce-
dure.

5) Change the height balance of the front frame side scanner rail.

[Rail adjustment]

1) Make a copy from the table glass, and check the copy out-

put.

In this case, set the test chart correctly. If it is set inclined,
the adjustment cannot be made correctly.

2) If the check result is outside the specified range, perform

the following procedure.

3) Remove the front cabinet on the scanner side, and check

the installing position of the MB rail.

4) Loosen the screw on the right side of the MB rail.

Repeat procedures 2) to 5) until the image distortions are bal-
anced.

6) Without changing the balance between the front frame side

scanner rail, change the overall height.

7) Set the test chart made in procedure 1) on the document

table, and make a copy on A3 (11" x 17") paper. Check that
the main scanning distortion is within the specified range.

Perform procedures 6) to 7) until the main scanning direction
distortion is in the specified range.

If this adjustment cannot remove the sub scanning direction distor-
tion, perform ADJ 6D, Scan image distortion adjustment.

If scan image distortion cannot be removed with ADJ 6A, ADJ 6B,
and ADJ 6C, perform this adjustment.

Change the position of the scanner unit distortion adjustment plate
on the right side of the scanner unit so that the scanner image dis-
tortion becomes minimum. The scan image distortion is adjusted
by adjusting the overall mechanical distortion of the scanner unit.

L

L

L

L

L = 10mm

Lc

Ld

Lc

Ld

Copy A

Copy B

There is no difference 

between the distortion on 

the right and that on the left.

Lc = Ld

There is some difference 

between the distortion on 

the right and that on the left.

Lc 

≠

 Ld

A

A

B

C

Scanner adjustment plate WH

B

C

AR-C172M  SETTING AND ADJUSTMENTS  8 - 18

This adjustment must be performed in the following cases:

• When the CCD unit is removed from the machine.

• When the CCD unit is replaced.

• When the copy image focus is improper.

• When the copy magnification ratio in the copy image main scan-

ning direction is not proper.

• When the MFP main PWB is replaced.

• When the EEPROM of the MFP main PWB is replaced.

• When a U2 trouble occurs.

1) Enter the SIM 48-1 mode.

2) Set the set item B to 50 (initial value).

3) As shown in the figure below, place a scale on the original

table.

4) Make a normal copy on A4 paper.

5) Compare the scale image length and the actual scale length.

6) Obtain the main scanning direction copy magnification ratio

according to the following formula.

Main scanning direction copy magnification ratio

=

x 100 [%]

(Example) Fit 10mm of the scale with 10mm of the copied scale

and compare them.

Main scanning direction copy magnification ration

=

x 100 = 1

If the copy magnification ratio is not satisfactory, perform the
following procedure.

7) Remove the original guide L and R, and remove the table

glass.

8) Remove the dark box cover.

9) To prevent against the optical axis shift of the CCD unit, mark

the CCD unit base as shown in the figure below.

∗

This procedure must be performed when replacing the CCD
unit.

10) Loosen the two fixing screws of the CCD unit. 

∗

✕

✕

✕

✕

If one of these screws is loosened, the CCD unit base posi-
tion and angle may be changed. If so, it cannot be adjusted
in the market, and therefore the whole scanner unit must be
replaced.

11) Slide the CCD unit in the arrow direction (CCD sub scanning

direction) to change the installing position.

When the copy image is longer than the original, move in the
direction of B.

When the copy image is shorter than the original, move in the
direction of A.

One scale of scribe line corresponds to 0.2%.

At that time, fix so that the CCD unit is in parallel with the scales
on the front frame side and on the rear frame side of the CCD unit
base.

∗

At that time, fix the CCD unit so that it is in parallel with the line
marked in procedure 9).

(Original dimension – Copy dimension)

Original dimension

100 – 99

100

10

20

90

100

110

10

20

90

100

110

100mm scale
(Original)

Copy image
(1mm (1%)
shorter than 
the original)

1.0mm

A

B

AR-C172M  SETTING AND ADJUSTMENTS  8 - 19

12) Make a copy, and check the copy magnification ratio.

If the copy magnification ratio is outside the range of 100% ± 1%,
repeat procedures 9) to 11) until it is in the range.

Note: Due to the structure of the optical system, when the CCD

unit fixing position is changed with SIM 48-1 set to 50, the
copy magnification ratio is adjusted to the specified level
(100 ± 1.0%) and the specified resolution is provided.

This adjustment must be performed in the following cases:

• When the copy magnification ratio in the copy image sub scan-

ning direction is improper.

• When the scanner motor is replaced.

• When a U2 trouble occurs.

• When the MFP main PWB is replaced.

• When the EEPROM of the MFP main PWB is replaced.

Before this adjustment, perform the focus adjustment (CCD unit
installing position adjustment).

1) Place a scale on the original table as shown below.

2) Enter the SIM 48-1 mode.

3) Make a normal copy and obtain the copy magnification ratios.

Copy magnification ratio

=

x 100 [%]

4) Check that the copy magnification ratio is within the specified

range (100 ± 1.0%).

If the copy magnification ratio is within the specified range
(100 ± 1.0%), the adjustment is completed.

If not, perform the following procedure.

5) Change the scan mode adjustment value of SIM 48-1.

When the adjustment value is increased, the sub scanning
direction copy magnification ratio is increased.

A change in the adjustment value by 1 corresponds to a
change in the copy magnification ratio by about 0.1%.

Repeat procedures 3) to 5) until the coy magnification ratio is
within the specified range (100 ± 0.28%).

Note: Fix the adjustment value of SIM 48-1 adjustment mode (F –

R) to 50.

This adjustment must be performed in the following cases:

When the scanner (reading) section is disassembled.

When the scanner (reading) unit is replaced.

When the RSPF section is disassembled.

When the RSPF unit is installed.

When the RSPF unit is replaced.

When a U2 trouble occurs.

When the MFP main PWB is replaced.

When the EEPROM of the MFP main PWB is replaced.

1) Make a copy in the adjustment chart adjustment mode. (Docu-

ment table or RSPF)

2) Check the copy image center position.

If A – B = ± 1.0mm, there is no need to adjust.

If the above condition is not satisfied, perform the following
procedures.

3) Enter the SIM 50-12 mode.

4) Select the adjustment mode with the scroll key.

5) Enter the adjustment value with the 10-key and press the [OK]

key.

The entered value is set.

∗

When the set value is increased, the main scanning print posi-
tion is shifted by 0.1mm to the front side.

Repeat procedures 2) to 5) until the above condition is satisfied.

(Original dimension – Copy dimension)

Original dimension

10

20

90

100

110

10

20

90

100

110

10

20

90

100

110

(Example 2) 
Copy B
(Longer than 
the original)

(Example 1) 
Copy A
(Shorter than 
the original)

Scale 
(Original)

A

B

A – B =   1.0mm

(100%)