Engine Section - Sharp AR-M450 Service Manual

2. Engine section

A. LSU right angle adjustment
This adjustment is required in the following cases:
•When the LSU is replaced.
•When a distortion is generated in printer output.
(Check with self-print pattern "71.")
After completion of this adjustment, perform the following adjustments:
•Print off-center adjustment
•Void area adjustment
1) Execute SIM 64-1.
2) Make self-print of print pattern 71 and grid pattern from tray 1.
3) Check the self-printout.
<Right angle check method>
<1> Make a self-print pattern 71.
<2> Draw a line perpendicular to the sub scanning direction
(paper transport direction) with a square.
At that time, let the point of intersection of the perpendicular line
and the horizontal line be the start point.
<3> Measure distance A at a position 220mm apart from the point of
intersection of the vertical line outputted by self print and the line
drawn with a square.
<4> Check that distance A satisfies the specification below.
A
Print
lead edge
220mm
4) If the printout is out of the specifications, perform the following
procedures.
5) Loosen two screws (M4) which are fixing the LSU.
6) Turn the adjustment screw on the upper side (rear of the printer
operation panel) clockwise and counterclockwise to adjust the height
of the LSU front side.
7) After completion of adjustment, tighten the two fixing screws of the
LSU unit.
8) Print the grid pattern again and check it.
9) Repeat procedures 7) to 10) until the printout is in the specified
range.
10) After completion of the work, apply screw lock to the screws.
<Specifications>
Print distortion
adjustment
B. Print off-center adjustment
This adjustment is performed in the following cases:
•When the center is misaligned in printing.
•When the LSU is replaced.
•When the option paper feed unit or the automatic duplex unit is installed
or replaced.
Before execution of this adjustment, the following adjustments must have
been completed.
•LSU right angle adjustment
•Print magnification ratio adjustment
A
After completion of this adjustment, the following adjustment must be
executed.
•Void area setup
1) Execute SIM 50-10.
2) Set the paper fed tray and the magnification ratio for the adjustment.
3) After entering the adjustment values, press START key, and printing
4) Check the off-center (distance from the paper edge) of the printed
*
AR-M350 ADJUSTMENTS 9-2
Print lead edge
Measurement
position
SIM 64-1
Self-print pattern
71
is started.
copy. Repeat procedure 2) until the specification is satisfied.
When adjusting the off-center of LCC1, load paper only on the left
tray of LCC.
When adjusting the off-center of LCC2, load paper only on the right
tray of LCC.
This is because no distinction of right and left is made when
selecting a tray.
=
Print lead edge
>
Specification ± 1.5mm
a b
Specification Set value
=90°±0.13° Adjustment
scale 1 = about
0.25° shift in