Adjust Dspf Skews - Sharp MX-M550U Service Manual

4-B

Adjust DSPF skews

This adjustment is needed in the following situations:
* The DSPF section has been disassembled.
* The DSPF unit has been replaced.
* The DSPF unit generates skewed scanned images.
1) Create an adjustment chart by printing in duplex mode the self-
print pattern (grid pattern) specified in Simulation 64-1.
Make sure that the print grid pattern is almost in parallel with
the paper edges, and apply position marks 'A', 'B', 'C' and 'D' to
the leading and trailing edges of the paper for both front and
back sides of the paper.
A
2) Copy the adjustment chart (created in step 1) to A3 (11" x 17")
paper in duplex mode, and then check the image for skews
(Set in the DSPF feed tray so that the mark on the adjustment
chart is at the edge).
Check with one of the following methods.
[Check Method 1]
(Front side)
Make sure that the output satisfies the condition: |a-b|
A
a
(Back side)
Make sure that the output satisfies the condition: |c-d|
C
c
B
1mm
B
b
1mm
D
d
MX-M700N ADJUSTMENTS 6 – 13
[Check Method 2]
Check that the squareness of the main scanning direction print
line for the longitudinal direction of paper is within 0.5mm.
If the above requirement is met for the copied image of the
paper's front side but not for the paper's back side, skip to step
4.
If the above requirement is not met for the paper's front side,
then do step 3.
3) Loosen the hinge screws and lower the two attachments.
4) Open the DSPF and loosen the screw.
A