JUKI LU-2800 Series, Руководство инженера

Страница: 124 / 143

– 1
12 –
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the sewing machine.
Trouble Cause Checking Corrective measures
1. Thread breakage 1-1) Thread path, needle point, hook blade
point or innerhook resting groove on
the throat plate has sharp edges or
burrs.
1-A) Check the sharp edge or burr
on the respective parts.
Remove the sharp edges or burrs on the blade
point of hook using a fine emery paper.
Buff up the groove section on the throat plate.
Replace the needle with a new one.
2. Thread is worn out. 2-1) Needle thread tension is too high. Adjust the needle thread tension.
2-2) Needle comes in contact with the
blade point of hook.
2-A) Check the clearance. Refer to “2.-(6) Needle-to-hook timing”.
2-3) Clearance of opener is too large. 3-A) Check the clearance. Decrease the clearance.
Refer to “2.-(5) Adjusting the opener”.
2-4) Amount of oil in the hook is insuffi -
cient.
4-A) Check the amount of oil in the
hook.
Adjust the amount of oil in the hook.
Refer to “2.-(15) Lubrication”.
2-5) Trimmed with the tooth of the feed
dog.
5-A) Check the feed dog. Provide a groove behind the feed dog needle hole.
5-B) Check the alternate vertical
movement.
Reduce the amount of alternate vertical move-
ment.
5-C) Check the sewing speed. Reduce the sewing speed.
8. Troubles and corrective measures
(1) With regard to sewing