Sharp AR-BC260 Service Manual page 110

ADJ 6C Copy image main scanning direction
distortion adjustment
1) Make a test chart on A3 (11" x 17") paper as shown below.
(Draw a rectangle with four right angles.)
L
L
L
2) Set the test chart made in procedure 1) on the document
table. With the document cover open, make a copy on A3 (11"
x 17").
3) Check for distortion in the main scanning direction.
If the four angles of the rectangle on the copy are right angles,
there is no distortion. (Completion of the adjustment)
If there is some distortion in the main scanning direction, perform
the following procedures
4) Check the difference (distortion balance) of left and right
images distortions.
Lc
Copy A
Ld
There is no difference
between the distortion on
the right and that on the left.
Lc = Ld
If Lc = Ld, the distortion on the left is equal to that on the right.
(The distortions are balanced.)
If the above condition is satisfied, go to procedure 6).
If the above condition is not satisfied, perform the following proce-
dure.
5) Change the height balance of the front frame side scanner rail.
[Rail adjustment]
1) Make a copy from the table glass, and check the copy out-
put.
In this case, set the test chart correctly. If it is set inclined,
the adjustment cannot be made correctly.
2) If the check result is outside the specified range, perform
the following procedure.
3) Remove the front cabinet on the scanner side, and check
the installing position of the MB rail.
L
L = 10mm
Lc
Copy B
Ld
There is some difference
between the distortion on
the right and that on the left.
Lc ≠ Ld
AR-BC260 SETTING AND ADJUSTMENTS 8 - 17
4) Loosen the screw on the right side of the MB rail.
Repeat procedures 2) to 5) until the image distortions are bal-
anced.
6) Without changing the balance between the front frame side
scanner rail, change the overall height.
7) Set the test chart made in procedure 1) on the document
table, and make a copy on A3 (11" x 17") paper. Check that
the main scanning distortion is within the specified range.
Perform procedures 6) to 7) until the main scanning direction
distortion is in the specified range.
If this adjustment cannot remove the sub scanning direction distor-
tion, perform ADJ 6D, Scan image distortion adjustment.
ADJ 6D Scan image distortion adjustment
If scan image distortion cannot be removed with ADJ 6A, ADJ 6B,
and ADJ 6C, perform this adjustment.
Change the position of the scanner unit distortion adjustment plate
on the right side of the scanner unit so that the scanner image dis-
tortion becomes minimum. The scan image distortion is adjusted
by adjusting the overall mechanical distortion of the scanner unit.
B
B
A
A
C
Scanner adjustment plate WH
C