Sharp MX 3501N - Color Laser - Copier, Service Manual

Page: 70 / 448

MX3500N ADJUSTMENTS 6 – 25
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)."
11-D Scan image distortion 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.
ADJ 12
Scan image focus adjustment
(CCD unit position adjustment)
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 press [OK] key.
3) Place a scale on the document table as shown in the figure
below.
4) Make a normal copy on A4 paper.
Press [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
A
A
A
A
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
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