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WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the sewing machine
Trouble
Cause (1)
Cause (2)
Check and corrective measures
3. Needle breakage
3-1) Needle entry
1-A) Needle hits the throat plate or presser
foot because the needle entry is not
correctly positioned for the plate or
foot.
Align the needle entry to the needle.
3-2) Spreader
2-A) Too little clearance between spreader
and needle.
Refer to the standard adjustment figures.
3-3) nterference of looper with
scooping movement of
needle
3-A) Needle hits looper resulting in needle
breakage.
Make adjustment so that looper does not hit
the looper. For the correction of the contact at
looper’s back, adjust the moving amount, front
and rear.
3-4) Needle guard
4-A) Too strong contact against needle
guard or needle point hits needle
guard due to incorrect position.
Refer to the standard adjustment figures.
3-5) Needle thickness No.
5-A) Too thin needle for fabric used.
Use thicker needle.
3-6) Thread tension
6-A) Needle thread tension is too strong.
Reduce the needle thread tension.
3-7) Feed dog height, Needle
height
7-A) Feed dog is too high or needle height
is too low resulting in needle break-
age due to needle swerve.
Refer to the standard adjustment figures.
3-8) UT59
Thread hook
8-A) Needle hits thread hook.
Check to be sure that air is supplied.
Check to be sure that thread hook is located in
the standby position.
4. Worn out needle point
4-1) Needle guard
1-A) Incorrect height or incorrect position,
front and rear
Check to see the height of needle guard and
clearance between needle guard and needle.
4-2) Interference with looper
2-A) Moving amount, front and rear is ill
balanced.
Adjust moving amount, front and rear and cor-
rect the incorrect position of looper’s back and
the contact when it returns.
4-3) UT59
Thread hook
3-A) Needle hits thread hook.
Refer to "12.-(9) Setting the raveling preven-
tion parameter".
