Sharp AL-1000 Service Manual page 52

AL-1000/1010
10) Check the horizontal image distortion.
If LL = LR, there is no horizontal distortion
LL and LR: Distance between the copy
LL LR
Black background
11) If LL is not equal to LR, perform the following proce-
dure.
Loosen the setscrew of the copy lamp unit/No.2/3 mirror
unit drive pulley in the front or the rear frame.
Scanner unit drive pulley
12) Without moving the copy lamp unit/No.2/3 mirror unit
drive pulley shaft, manually turn the copy lamp
unit/No.2/3 mirror unit drive pulley whose setscrew was
loosened, and adjust the parallelism of copy lamp
unit/No.2/3 mirror unit.
13) Tighten the set screw of the copy lamp unit/No.2/3 mir-
ror unit drive pulley.
14) Check the image distortion in the same manner as step
10).
Repeat procedures 11) to 14) until horizontal image dis-
tortion is eliminated.
image horizontal line and
the edge of the black
background.
Set screw
b. Vertical image distortion adjustment
I. Summary
In this adjustment, the left and right balance is adjusted by
changing the left and right balance of the No. 2 scanner unit
frame on the front frame side.
II. Note
Horizontal image distortion adjustment
III. Cases when the adjustment is required
1) When the copy lamp unit/No.2/3 mirror unit drive section
is disassembled or its part is replaced.
2) When the copy image is distorted as follows:
Document
IV. Necessary tools
Screwdriver (+)
Screwdriver (–)
Scale
Test chart for distortion adjustment (Make by yourself.)
Draw a rectangle on A4 or 8 1/2" × 11" paper as shown
below:
Be sure to make four right angles.
L
V. Adjustment procedure
1) Set the test chart for image distortion adjustment on the
document glass, and make a normal copy on a paper of
A4 or 8 1/2" × 11".
2) Check image distortion in the right and the left sides.
If the both vertical lines are in parallel with each other,
the right-left distortion balance is proper. (However, there
may be some distortion.)
2) If all the four angles are right angles, there in no distor-
tion and the following procedures are not required.
Greater distortion
9-3
Copy C Copy D
L
L
L = 10mm
L
Smaller distortion