Sharp MX-2314N Service Manual page 65

(Skew adjustment screw rotation direction)
When C is greater than D in the method 1 or there is some
skew in the direction A in the method 2, turn the screw clock-
wise.
When C is smaller than D in the method 1 or there is some
skew in the direction B in the method 2, turn the screw coun-
terclockwise.
(Reference of the rotation amount of the skew adjustment
screw)
In case of the method 1, 0.8mm/about 1.5 rotations
In case of the method 2, 0.5mm/about 1.5 rotations
Repeat the procedures 2) to 6).
After completion of the black image skew adjustment, go to the
procedure 7).
6) Perform the same procedures as 1) and 2).
7) Check the printed color image for any skew.
If the difference between the shift amounts on the F and R
sides is within  1 scale of the fine adjustment check scale,
there is no need to perform the adjustment.
Measure the skew amount from the print patterns on the front
and rear sides of each color.
Color image shift check
scale (Fine adjustment)
B-sub
B-main
A-sub
A-main: Main scan rough adjustment pattern
A-sub: Sub scan rough adjustment pattern
B-main: Main scan fine adjustment scale
B-sub: Sub scan fine adjustment scale
C: Main scan sub scan fine adjustment pattern
In each Y/M/C color print pattern printed separately in the F
side and in the R side, note the same print color pattern and
check to confirm that the F side and the R side are in the same
condition.
Rough adjustment pattern check:
R side
F side
C (Image shift fine adjustment
reference frame)
A-main
Color image shift
check section
(Rough adjustment)
MX-3114N ADJUSTMENTS AND SETTINGS 5 – 16
Check the sub scan rough adjustment color image shift check
section on the R side and the F side of each color, use the cen-
ter position of the black scale as the reference, and check the
balance in shifts of the color image line positions in the positive
and the negative directions. The balance in the R side must be
the same as that in the F side.
Fine adjustment pattern check:
Check the square frames on the R side and the F side of each
color. (Normally five sections of high density can be seen.)
Check the sub scanning direction position of the center area of
high density (one of the above five sections). These must be
on the same position on the R side and the F side.
In this case, use the sub scan direction color image shift check
scale (fine adjustment) as the reference.
Visually check the color density and make the darkest section
as the center, and use it as the read value of the shift amount.
Check that the difference in the center position of the dark den-
sity section is within 1 step.
The positional relations of the front and the rear frame of the
print color patterns of a same color are compared. There is no
need that all the colors are in the same state. Compare only
the positional relations of color patterns of a same color.
If the above condition is not satisfied, perform the following
procedure.
8) Turn the LSU skew adjustment screw of the adjustment target
color to adjust.
(Skew adjustment screw rotation direction)
When the F side is skewed to the right side for R side: Turn the
screw clockwise.
When the F side is skewed to the left side for the R side: Turn
the screw counterclockwise.
(Reference of the rotation amount of the skew adjustment
screw)
Skew of difference by one step between F and R sides (Differ-
ence by one scale of the fine adjustment check scale) / Turn
for about 2 clicks.
Repeat the procedures 7) to 8) until a satisfactory result is
obtained.
5-C Color registration offset adjustment
(No need to adjust normally)
This adjustment is used to set the offset value for the automatic
color registration adjustment (ADJ 5A).
If there is any difference in color phase at the center and the four
corners of an actual print image, this adjustment may improve it.
Especially when there is any color shift at the center area, this
adjustment may improve it effectively.
This adjustment cannot eliminate color shifts in all the areas, but
average the overall color shifts.
After the automatic adjustment, use this color registration offset
adjustment to correct color shift partially, performing the adjustment
efficiently.
Before execution of this adjustment, check to confirm that the fol-
lowing adjustment has been properly made.
* ADJ 5A or ADJ 5B image skew adjustment (LSU unit)
[Kinds of adjustment values]
There are following two kinds of registration adjustment values.
• Base registration adjustment value: XXX(FRONT)/XXX(REAR)
They are manual adjustment values and automatic adjustment
values, and reflected when the automatic registration adjustment
is executed. It varies for every operation of the automatic regis-
tration adjustment.