JUKI MEB-3200 Engineer's Manual page 17

Adjustment Procedures
The standard adjustment value of the clearance between the
needle and the looper is 0.03 to 0.1 mm.
Loosen looper setscrew 1 and adjust the clearance between
needle 2 and left looper 3, and between the needle and right
looper 4.
Dimensions for reference
Clearance between the needle and needle guard 5 : 0 to 0.1 mm
Clearance between the needle and holder 6 : 0.2 mm
(Caution) Be sure to adjust the clearance wnen the needle
size is changed.
Adjustment Procedures
1. Provide a clearance of 0 to 0.1 mm between needle 2 and
needle guard 3.
2. Loosen setscrew 1 and move needle guard 3 back and forth
to adjust the clearance.
3. Tightn setscrew 1.
4. Check the clearance both at the time of inside needle and
outside needle.
(Caution) 1. Be sure to adjust the needle guard when the
needle size is changed or when the adjustment
of needle and looper is performed.
2. Adjust the clearance when needle aligns with the
looper blade point at the time of the inside needle
and outside needle respectively.
Adjustment Procedures
1. Installation position of left and right spreaders
1) Clearance A between left spreader 1 and the top surface
of left looper is as large as a piece of looper thread used.
2) The center of the top end of forked section of Left spreader
1 agrees with the center of looper thread hole of left looper.
3) Clearance between right spreader 4 and the top surface of
right looper is 0 to 0.1 mm.
4) Right spreader 4 agrees with the right spreader and the
crest line of the inside of right looper (needle side).
5) Loosen setscrew 2 in the spreader stopper and adjust the
position of spreader stopper 3 to fix the spreader. (Make
the same adjustment for both left/right spreaders.)
2. Timing to open/close the spreaders
1) Adjust so that the spreaders open/close equally on the left
and right without interfering with the needle.
2) Loosen setscrew 6 in spreader driving shaft guide 5 and
move the guide up and down to make the adjustment.
Results of Improper Adjustment
™ When the clearance is larger
than the specified value, stitch
skipping may occur.
Results of Improper Adjustment
Results of Improper Adjustment
™ When closing timing of the left
spreader is delayed, stitch
skipping may occur. (Loop
b e c o m e s s m a l l w h e n t h e
outside needle catches thread.)
™ When the clearance between
spreader and looper is smaller
or larger than the specified
value, stitch skipping or needle
breakage will be caused.
(Caution) Adjust the clearance
by correcting the spreader.
Using the cutting pliers or the
like causes breakage of the
spreader. Put a piece of
wooden board or the like on
the top end of spreader and
gradully bend it by hand.
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