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MX-1800N  ADJUSTMENTS  6 – 21

b)

Adjustment value calculation
Add or subtract the shift amount calculated above to or from the current adjustment value, and the result value is used as the new
adjustment value.
Adjustment value = Current adjustment value + Shift amount (correction value)
(When the shift amount (correction value) is plus)
Adjustment value = Current adjustment value – Shift amount (correction value)
(When the shift amount (correction value) is minus)

 

This adjustment is required 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. (For details, refer to Chapter [C]-3.)
1) Loosen the fixing screws of the scanner unit A and the drive

wire, and remove the scanner unit A from the drive wire.

A

B

C

A: 100

A: 73 (= 100 – 27)

B: 112

B: 119 (= 112 + 7)

C: 95

C: 110 (= 95 + 15)

MX-1800N  ADJUSTMENTS  6 – 22

2) Turn the scanner drive pulley manually and shift the scanner

unit B to bring it into contact with the stopper. When the scan-
ner unit B is in contact with the two stoppers on the front and
the rear frames simultaneously, the parallelism is proper.

If not, perform the following procedures.

3) Loosen the fixing screw of the pulley angle on the front frame

side of the scanner unit.

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
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.

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 with A3 (11" x 17") paper as shown below.
(Draw a rectangular with four right angles.)

L

L

L = 10mm

L

L

MX-1800N  ADJUSTMENTS  6 – 23

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 "ADJ 11D Scan image distortion
adjustment (whole scanner unit)."

 

1)

Make a test chart on A3 (11" x 17") paper. (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 copy image are right angles, there is
no distortion. (Completion of the adjustment)

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

4)

Check the difference (distortion balance) between the image
distortions on the right and the left.

If Lc = Ld, there is no difference between the right and the left
image distortions.
If the above condition is satisfied, go to the procedure 6).
If not, perform the following procedures.

La

Lb

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

There is some difference

between the distortion on

the right and that on the left.

Lc

≠ Ld

MX-1800N  ADJUSTMENTS  6 – 24

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) 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 "ADJ 11D Scan image dis-
tortion adjustment (Whole scanner)."

 

This adjustment is executed when scan image distortion cannot be
adjusted with ADJ 11A, ADJ 11B, and ADJ 11C 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.

 

This adjustment is required 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 not properly adjusted.
* When the copy magnification ratio in the copy image main scan-

ning direction is not properly adjusted.

* When a U2 trouble occurs.
1)

Enter the simulation 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 touch [OK] key.

3)

Place a scale on the document table as shown in the figure
below.

4)

Make a normal copy on A4 paper.
Touch [CLOSE] key to shift from the simulation mode to the
copy mode, and make a copy.

5)

Compare the scale length with the scale image length on the
copy paper.

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

CLOSE

0

A:

A㧦xx

B㧦xx

C㧦xx

D㧦xx

㧧

CCD(MAIN)

㧧

CCD(SUB)

㧧

SPF(MAIN)

㧧

SPF(SUB)

SIMULATION NO.48-01

MAGNIFICATION ADJUSTMENT

xx

1 99

OK

TEST