JUKI DDL-8000A, Руководство инженера

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Trouble Cause (1) Cause (2) Check and corrective measures
4. Stitch skipping
The machine fails to form a com-
plete stitch.
4-1) The needle is defective. 1-A) The needle is bent. Replace the needle.
1-B) The needle mounting direction
is inappropriate. The needle is
not mounted fully to the end.
Mount the needle appropriately. Replace the
needle clamp screw.
Defective sewing is likely to occur when the
needle recess portion faces frontward.
1-C) The needle tip is blunt. Replace the needle.
1-D) The needle is too thin or thick
for the thread to be used.
Replace the needle.
1-E) The feeding force is too weak. Lift the feed dog height.
4-2) The matters related to the
hook are inappropriate.
2-A) The blade top of the hook is
blunt or worn.
Sharpen the blade top of the hook or replace
the hook.
2-B) The timing of the hook is inap-
propriate.
Correct the timing. (The proper timing depends
on the type of material and thread. In general,
the timing should be set earlier for synthetic
thread or heavy-weight material, and it should
be set later for light-weight material.)
2-C) The height of the needle bar is
inappropriate.
Properly adjust it with respect to the hook
point.
2-D) The clearance between the
hook point and needle is wrong.
Minimize the clearance.
2-E) The loop shape is unstable.
(Mesh type materials)
Wind the needle thread or use the T-type
thread guide.(B1418227T00).
2-F) A needle holder does not exist. Replace the current hook with a hook with a
needle holder equipped. 11141355 for MS,
22890404 for SH
4-3) The tension of the needle
thread is too high.
Reduce the tension of the needle thread. Use
silicon.
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