DOWNLOAD Sharp MX-6500N / MX-7500N (serv.man19) Service Manual ↓ Size: 5.74 MB | Pages: 98 in PDF or view online for FREE

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 17

*1 To adjust with the center area most focused, adjust so that
the color shift at the center becomes smaller than that on the F
side and the R side.

Adjust the most high density position of the check patterns in
order to be stayed in the color registration adjustment standard
frame of center.

(Adjust the center of the most high density position to scale 0)

To make the whole shift small averagely and to adjust the shift
of each pattern equally.

Exsample)  In case if the pattern 1 is adjust to the scale 0, the
image of pattern 2 shift to opposite direction.

Reference adjustment value:1 scale / 2 adjustment value

If the most high density position is at +10 (The 5th scale), input
the adjustment value -10 from the current value.

 

This adjustment must be performed in the following cases:

* When the scanner (reading) section is disassembled.

* When the copy image is distorted.

 

Before execution of this adjustment, remove the document table
glass.

1)

Remove the lamp unit, and then loosen the screws which are
fixing the scanner unit A and the drive wire. Release the scan-
ner unit A from the drive wire.

2)

Turn the scanner drive pulley manually and shift the scanner
unit B to bring it into contact with the stopper.

When the scanner unit B is in contact with the two stoppers on
the front and the rear frames simultaneously, the parallelism is
proper.

If this requirement is not met, do the following steps.

3)

Loosen the fixing screw of the pulley angle on the front frame
side of the scanner unit B.

4)

Adjust the position of the pulley angle on the front frame side
of the scanner unit B so that it is in contact with two stoppers
on the front and the rear frames simultaneously.

5)

Fix the pulley angle on the front frame side of the scanner unit
B.

If a satisfactory result is not obtained from the above proce-
dures, perform the following procedures.

Loosen the fixing screw of the scanner unit drive pulley which
is not in contact.

Without moving the scanner unit drive shaft, turn the scanner
unit drive pulley manually and adjust so that the scanner unit B
is in contact with both stoppers on the front frame and the rear
frame simultaneously. (Change the relative position of the
scanner unit drive pulley and the drive shaft.) Fix the scanner
unit drive pulley fixing screw.

***(FRONT) OFFSET_*_F

Front pattern 1/2

***(REAR OFFSET_*_R

Rearpattern 1/2

***(SUB)OFFSET_*_S

All pattern 1/2 *1 

㻯㼛㼘㼛㼞㻌㼕㼙㼍㼓㼑㻌㼟㼔㼕㼒㼠㻌㼏㼔㼑㼏㼗㻌㼟㼏㼍㼘㼑㻌
㻔㻿㼡㼎㻌㼟㼏㼍㼚㼚㼕㼚㼓㻌㻌㼐㼕㼞㼑㼏㼠㼕㼛㼚㻕

㻵㼙㼍㼓㼑㻌㼟㼔㼕㼒㼠㻌㼒㼕㼚㼑㻌㼍㼐㼖㼡㼟㼠㼙㼑㼚㼠㻌

㼒

㼒

check

scale

(Main

rection)

㼞㼑㼒㼑㼞㼑㼚㼏㼑㻌㼒㼞㼍㼙㼑

image

shift

scanning

di

r

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 18

6)

With the scanner unit B in contact with both stoppers, fit the
edge of the scanner unit A with the right edge of the frame, and
fix the scanner unit A with the fixing 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 prepared in the procedure 1) on the docu-
ment table. (Shift the test chart edge 30mm from the reference
position as shown below.) With the document cover open,
make a copy on A3 (11" x 17") paper.

3)

Check for distortion in the sub scanning direction.

If La = Lb, there is no distortion.

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

4)

Loosen either one of the fixing screws of the scanner unit drive
pulley. (Either one on the front frame or on the rear frame will
do.)

5)

Without moving the scanner unit drive shaft, manually turn the
scanner unit drive pulley to change the parallelism of the scan-
ner unit A and B. (Change the relative position of the scanner
unit drive pulley and the drive shaft.)

6)

Tighten the scanner unit drive pulley fixing screw.

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

If the distortion in the sub scanning direction cannot be deleted with
the above procedures, perform ADJ5D Scan image distortion
adjustment (Whole scanner unit).

L

L

L = 10mm

L

L

30mm

La

Lb

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 19

 

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 prepared in the procedure 1) on the docu-
ment table, and make a copy on A3 (11" x 17") paper.

3)

Check for distortion in the main scanning direction.

If the four angles of the rectangle of the copy image are right
angles, it is judged that there is no distortion. (The work is
completed.)

If there is any distortion in the main scanning direction, perform
the following procedure.

4)

Check the difference (distortion balance) between left-hand
and right-hand side 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 the procedure 6).

If not, perform the following procedures.

5)

Change the height balance of the scanner rail on the front
frame side.

Remove the lower cabinet of the operation panel. Loosen the
scanner rail fixing screw to change the balance between the
right and the left heights of the scanner rail.

Repeat the procedures 2) - 5) until the difference between the
image distortions (distortion balance) is deleted.

6)

Without changing the balance of the scanner rail on the front
frame side, change the overall height.

7)

Set the test chart prepared in the procedure 1) on the docu-
ment table, and make a copy on A3 (11" x 17") paper. Check
that the distortion in the main scanning direction is within the
specified range.

Repeat the procedures 6) and 7) until the distortion in the main
scanning direction is in the specified range.

If the distortion in the sub scanning direction cannot be deleted with
the above procedures, perform ADJ5D Scan image distortion
adjustment (whole scanner unit).

 

This adjustment is executed when scan image distortion cannot be
adjusted with ADJ5A, ADJ5B, and ADJ5C related to the scan
image distortion adjustment.

Change the upper and lower positions of the scanner unit distortion
adjustment plate on the right edge of the scanner unit so that the
scan image distortion is minimized. By adjusting the distortion of
the whole scanner unit, the scan image distortion is adjusted.

1)

Loosen the fixing screw (A).

2)

Adjust the scanner unit distortion adjustment plate.

L

L

L = 10mm

L

L

Lc

Ld

Copy A

Lc

Ld

Copy B

There is no difference
between the distortion on
the right and that on the left.

Lc     Ld

Lc     Ld

There is some difference
between the distortion on
the right and that on the left.

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 20

 

 

This adjustment must be performed in the following cases:

* The DSPF section has been disassembled.

* The DSPF unit has been replaced.

* When a DSPF JAM is generated.

* When a skew is generated in the document feed operation.

* When there is a distortion (skew) in the scan image in the DSPF

unit.

1)

Close the DSPF unit and check the clearance between the
projections in the front side and the rear side and the SPF
glass holding resin surface.

2)

Visually check to insure that the clearance A is 1mm or less
and the clearance B is 0mm (in contact).

If the above requirement is not met, do step 3).

3)

Turn the height adjustment screw to adjust the DSPF front/rear
frame horizontal level.

When the front frame side is higher (there is a clearance in B):
Turn the height adjustment screw R of the DSPF rear frame
clockwise.

When the rear frame side is higher (clearance A is more than
1mm): Turn the height adjustment screw L of the DSPF rear
frame counterclockwise.

Repeat steps 2) to 3) until an acceptable result is obtained.

4)

After adjustments of A and B, check to insure that the projec-
tion on the front right side is in contact with the glass surface of
the main unit.

 

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.

A

B

0mm

1mm

R

L