Sharp MX-2314N Service Manual page 64

When the adjustment is made by turning the LSU skew adjustment
screw of K, the states of C, M and Y (SKEW) are changed. Execute
SIM50-22 to check to confirm that C, M, and Y (SKEW) are OK.
When an abnormality occurs, "ERROR" is displayed.
In this case, check each drive section and the process section.
The adjustment result can be checked by the following manual
adjustment mode.
* ADJ 5B
Image skew adjustment (Manual adjustment) (SIM50-20)
* ADJ 5C
Color registration offset adjustment (SIM50-20)
When the color registration is greatly shifted due to replacement of
the LSU, etc, if SIM50-22 is used to perform the color registration
automatic adjustment, an error may occur.
In this case, the adjustment may be properly executed by setting
the adjustment items A - I of SIM50-20 to "100" and executing the
automatic adjustment again.
If color shift in an actual print image differs in the center, the front
side, and the rear side, the color shift offset adjustment can
improve it. (Refer to ADJ 5C.)
Normally there is a difference in color shift in several dots. Perform
the adjustment only when the adjustment is required.
5-B Print engine image skew (LSU skew)
adjustment (Manual adjustment)
(No need to adjust normally)
If a more accurate adjustment than the automatic adjustment ADJ
5A is required, use this method of adjustment.
This adjustment is made by changing the parallelism of the LSU
unit scan laser beams for the OPC drum.
1) Enter the SIM 50-20 or 64-01 mode.
2) Select the paper feed tray with A3 (11" x 17") paper in it, and
press [EXECUTE] key.
3) The image skew (image registration) adjustment pattern is
printed.
4) Check the printed black image for any skew.
Use the four cross points printed in black to measure the
squareness.
There are following two methods of checking the black image
for any skew (right angle).
Method 1
Measure the distances between opposing corners of the rect-
angle print pattern, and compare the two distances to check
the squareness.
MX-3114N ADJUSTMENTS AND SETTINGS 5 – 15
Method 2
Check the squareness of the vertical and horizontal sides of
the rectangle print pattern by using A3 or 11" x 17" paper
sides.
In the case of Method 2, the right angle of paper to be used
may not be exact. Be sure to check the right angle of paper to
be used in advance.
A B
Diagonal
line C
Method 1
Measure the length of the diagonal lines of the rectangle print
pattern.
Calculate the difference between the measured lengths C and
D of the diagonal lines.
Check to insure that the difference between C and D is in the
following range.
C - D = 0.8mm
If the difference between C and D is in the above range, there
is no need to adjust.
Method 2
Fit the side of A3 or 11" x 17" paper to the long side of the rect-
angle print pattern.
Measure the slant (skew) of the vertical side for the horizontal
side of paper as shown in the figure.
If the above distance is 0.5mm or less, there is no need to
adjust.
If the above condition is not satisfied, perform the following
procedure.
5) Open the front cover, remove the waste toner box, and turn the
four LSU image skew adjustment screws in the same direction
by the same amount.
For the adjustment, remove the front cover and the waste
toner box, and turn the skew adjustment screw.
Diagonal
line D
About 300mm