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MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 21

2)

Copy the adjustment chart (created in step 1) to A3 (11" x 17")
paper in DSPF duplex mode, and then check the image for
skews (Set in the DSPF feed tray so that the mark on the
adjustment chart is at the edge). 

-  Check with one of the following methods.

[Check Method 1]

[Check Method 2]

Check that the squareness of the main scanning direction
print line for the longitudinal direction of paper is within
1.0mm.

If the front surface copy image is as shown above and the
back surface copy is not as shown above, go to the step 3)
of "ADJ6C DSPF skew adjustment (Back surface mode)."

If the above requirement is not met for the paper's front side,
then do step 3).

3)

Loosen the hinge screws and lower the two attachments.

4)

Open the DSPF and loosen the screw.

5)

Adjust by turning the DSPF skew adjusting screw on the right
side of the DSPF rear frame.

[When the main scanning direction print line is shifted to the
left]

If a < b, then turn counterclockwise the DSPF skew 
adjusting screw.

[When the main scanning direction print line is shifted to the
right]

If a > b, then turn clockwise the DSPF skew adjusting screw.

Repeat steps 2) to 5) until an acceptable result is obtained.

Paper pass direction

a

b

c

d

(Front side)
Make sure that the output satisfies the condition: |a-b| ± 1 mm

(Back side)
Make sure that the output satisfies the condition: |c-d| ± 1 mm

0 - 1.0mm

1

2

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 22

 

This adjustment must be performed in the following cases:

* The DSPF section has been disassembled.

* When replacing the DSPF unit.

* The DSPF unit generates skewed scanned images.

1)

Make an adjustment chart.

Print the self print pattern (grid pattern) of SIM64-2 in the
duplex print mode.

A=1, B=1, C=254, D=255

Make sure that the print grid pattern is almost in parallel with
the paper edges, and apply position marks 'A', 'B', 'C' and 'D' to
the leading and trailing edges of the paper for both front and
back sides of the paper.

2)

Copy the adjustment chart (created in step 1) to A3 (11" x 17")
paper in DSPF duplex mode, and then check the image for
skews (Set in the DSPF feed tray so that the mark on the
adjustment chart is at the edge). 

-  Check with one of the following methods.

[Check Method 1]

[Check Method 2]

Check that the squareness of the main scanning direction
print line for the longitudinal direction of paper is within
1.0mm.

If the back surface copy image is as shown above and the
front surface copy is not as shown above, go to the step 3)
of "ADJ6B DSPF skew adjustment (Front surface mode)."

If the back surface copy is not as shown above, perform the
procedures of step 3) or later.

3)

Open the upper door, and remove the adjustment cover.

4)

Turn the DSPF skew adjustment screw on the CCD unit to
adjust.

Paper pass direction

a

b

c

d

(Front side)
Make sure that the output satisfies the condition: |a-b| ± 1 mm

(Back side)
Make sure that the output satisfies the condition: |c-d| ± 1 mm

0 - 1.0mm

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 23

[When the main scanning direction print line is shifted to the
left]

If c < d, turn the DSPF skew adjustment screw A 
counterclockwise, or turn the adjustment screw B clockwise.

[When the main scanning direction print line is shifted to the
right]

If c > d, turn the DSPF skew adjustment screw A clockwise,
or turn the adjustment screw B counterclockwise.

* The adjustment screws A and B must be turned in proper

balance. For example, if the trouble is not removed by turn-
ing the adjustment screw A 180 degrees clockwise, do not
turn the adjustment screw A furthermore, but turn the adjust-
ment screw B 180 degrees counterclockwise.

Repeat steps 2) to 5) until an acceptable result is obtained.

 

 

This adjustment must be performed in the following cases:

* The CCD unit has been removed from the machine.

* The CCD unit has been replaced.

* When the copy image focus is not properly adjusted.

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

ning direction is not properly adjusted.

* U2 trouble has occurred.

1)

Enter the SIM 48-1 mode.

2)

Set the adjustment item CCD (MAIN) to 50 (default value).

Select the adjustment item with the scroll key, and enter the
adjustment value with 10-key and press [OK] key.

3)

Place a scale on the original table as illustrated below.

4)

Make a normal copy on A4 paper.

Go to the copy mode, and make a copy.

5)

Compare the copied image of the scale and the actual scale
length in terms of length.

6)

Obtain the copy magnification ratio correction ratio in the main
scanning direction from the following formula.

Main scanning direction copy magnification ratio correction
ratio = (Original size - Copy image size) / Original size x 100%

(Example) 
Compare the scale of 10mm with the scale of 10mm on the
copy image.

Main scanning direction copy magnification ratio correction
ratio = (100 - 99) / 100 x 100 = 1

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

7)

Remove the document table glass.

8)

Remove the dark box cover.

9)

To prevent against shift of the CCD unit optical axis, mark the
CCD unit base as shown below.

NOTE: This procedure must be executed also when the CCD unit

is replaced.

10) Loosen the CCD unit fixing screws.

NOTE: Never loosen the screws marked with X.

If any one of these screws is loosened, the position and the
angle of the CCD unit base may be changed to cause a
problem, which cannot be adjusted in the market. In that
case, the whole scanner unit must be replaced.

 

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10

20

90

100

110

10

20

90

100

110

1.0mm

100mm scale
(Orignal)

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

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 24

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 scale, shift the
CCD unit in the direction B. When the copy image is shorter
than the original scale, shift the CCD unit in the direction A.

One scale of mark-off line corresponds to 0.2%.

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

* Fix the CCD unit so that it is in parallel with the line marked

in procedure 9).

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

If the copy magnification ratio is not in the range of 100 +/- 1%,
repeat the procedures of 9) - 11) until the condition is satisfied.

NOTE: By changing the CCD unit fixing position with the simula-

tion 48-1 adjustment value at 50, the copy magnification
ratio is adjusted within the specified range (100 +/- 1.0%)
and the specified resolution is obtained based on the opti-
cal system structure.

 

This adjustment must be performed in the following cases:

* When the DSPF CCD unit is replaced.

* When the DSPF CCD unit is replaced.

* When the COPY/SCAN/FAX image focus is not properly

adjusted.

* When the DSPF unit is removed.

* When the DSPF unit is replaced.

1)

Make a duplex copy in DSPF mode.

2)

Make sure that the copied image on the back side of the paper
is satisfactorily focused.

If the image is not satisfactorily focused, do the following
steps.

3)

Open the door. Remove the screws, and remove the transport
PG upper.

4)

To prevent against shift of the CCD unit optical axis, mark the
CCD unit base as shown below.

5)

Loosen the CCD unit fixing screws (4 pcs.).

* Never loosen the screws marked with 5.

Loosening these screws could possibly change the CCD
unit base optical axis. Once the optical axis has been
changed, it cannot be corrected through on-site adjust-
ments. Solving such a problem requires the replacement of
the entire scanner unit.

6)

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 scale, shift the
CCD unit in the direction B. When the copy image is shorter
than the original scale, shift the CCD unit in the direction A.

One scale of mark-off line corresponds to 0.2%.

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

* Fix the CCD unit so that it is in parallel with the line marked

in procedure 4).

7)

Make a copy and check the copy magnification ratio again.

If the copy magnification ratio is not in the range of 100 +/- 1%,
repeat the procedures of 4) - 6) until the condition is satisfied.

NOTE: By changing the CCD unit fixing position with the simula-

tion 48-1 adjustment value at 50, the copy magnification
ratio is adjusted within the specified range (100 +/- 1.0%)
and the specified resolution is obtained based on the opti-
cal system structure.
 

A

B