JUKI MO-6000S series, Руководство инженера

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6. TROUBLES AND CORRECTIVE MEASURES
Trouble Case (1) Case(2) Check and Corrective measures Page
1. Needle thread breakage Threading
Thread path
Needle guard
Needle
Needle heat
Thread
Thread tension
Contact
Double thread hooking (only for double chain stitch)
Deffective double chain-off thread (only for double
chain stitch)
Threading
The thread is entangled with the thread guide, or the
machine head has been incorrectly threaded.
Scratches, burrs or rust on the pawls or needle holes of
the throat plate, stitch tongue, lower looper, double chain
looper, needle thread take-up, needle thread presser
spring, thread guide, or tension discs causes friction.
The needle hits the needle guard intensely, and sharp
edges are produced on them, causing thread breakage.
The needle is too thin for the thread.
The needle gets very hot, depending on the type of
materials, number of plies and sewing speed, and
causes the thread to burn and break.
The thread is weak because of its poor quality.
The thread tension is too high.
The double chain looper or lower looper has been
improperly positioned and strikes the feed dog or throat
plate.
Poor drawing up of the needle thread causes the looper
to catch it again.
Refer to the clause referring to defective double chain-
off thread.
The thread is entangled with the thread guide, or the
looper has been incorrectly threaded.
Refer to the threading diagram.
Remove such scratches, burrs, etc. and perform thread
path finishing. Replace major components such as looper,
which have been deformed, causing thread breakage.
Replace the needle and needle guard if they have worn,
Replace the needle by a proper one.
Use a thinner needle. Reduce the sewing speed. Use the
needle cooler. Use an S-point needle or needle for
synthetic thread.
Replace the thread by one with good quality.
Reduce the thread tension. Check whether the needle
thread take-up guide and needle thread guide are
positioned too high, causing such excessive thread
tension.
Properly position the double chain looper or lower looper.
Increase the needle thread tension. Properly position the
thread cam. Properly position the double chainstitch
thread guide.
Refer to the treading diagram.
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