Sharp AR-250, Service Manual

Page: 60 / 196

(AR-250/281/286/287/336/337/405/407/501/505/507)
(2) Vertical image distortion balance adjustment
(No. 2/3 mirror base unit installing position
adjustment)
This adjustment is to adjust the parallelism of the mirror base to the
OPC drum surface and the original surface.
1) Manually turn the mirror base drive pulley to bring mirror base B
into contact with mirror base positioning plate.
If, at that time, the front frame side and the frame side of mirror
base B are brought into contact with the mirror base positioning
plate simultaneously, the parallelism is correct and there is no
need for adjustment.
Illust: AR-280
(3) Vertical (sub scanning direction) distortion
adjustment [Winding pulley position adjustment]
This adjustment is executed in the following cases:
·
When the mirror base drive wire is replaced.
·
When the lamp unit, or No. 2/3 mirror holder is replaced.
·
When a copy shown below is made.
1) Set A3 white paper on the original table as shown below.
illust: AR-280
2) With the original cover open, make a normal (X 1.0) copy.
3) Measure the black distance at the lead edge and the rear edge of
the copy paper.
If La = Lb, the procedures 4) through 7) are not required.
25~30mm
Lb
La
Original
Paper exit
direction
Copy
Allow a little space.
Glass holding plate
Fit the paper edge and
the glass holding plate edge.
A3 white paper
Paper exit direction
La: Lead edge black background section
Lb: Rear edge black background section
7/13/2000 6 – 10