ā 19 ā
1) For 1-needle or 2-needle overlock machine
1
Adjust needle guard
A
with setscrews in the needle guard so that
it lightly comes in contact with the needle when the blade point of the
lower looper reaches the needle center.
2
To adjust the clearance provided between needle guard
B
and the
needle when the needle bar is at the lowest point of its stroke, loosen
setscrews in the needle guard support and turn needle guard
B
to
adjust the clearance to 0.1 mm.
3
Adjust the height of needle guard
B
to 1 mm from the throat plate
bottom surface with setscrew in the needle guard.
2) For safety stitch machine
1
Loosen setscrews in the needle guard, and adjust the clearance
provided between needle guard
C
and the needle so that it lightly
comes in contact with the needle.
2
Adjust the installing height of needle guard
C
to 5 mm with setscrew
in the needle guard.
3
Adjust the clearance provided between needle guard
D
and the needle
to 0.1 mm with setscrews .
(Caution) Check again the clearance provided between needle guard
B
and the needle after adjusting the height of needle
guard
C
.
o Excessively close contact
between the needle guard
A
and the needles will lead to
needle bend or stitch skipping.
oA clearance left between the needle
guard
A
and the needles will cause
the looper blade point to come in
contact with the needles, leading to
needle or blade point breakage, or
other troubles.
o If the needle guard
B
is too high,
thread loops will be damaged
with resultant stitch skipping.
Also, double chain loops will be
affected, causing double chain
stitch skipping.
o If the needle guard
B
is too low,
the needle cooling felt will be low-
ered, resulting in deteriorated effect
of the cooling and needle guard.
oExcessive clearance between
the needle guard
B
and the
needle will cause stitch skipping
due to needle shake. On the con-
trary, insufficient clearance will
cause the needle guards to catch
the needles between them, lead-
ing to wear on the needle guards
and scratches on the needles.
o If the needle guard
C
is too high,
the needle thread loops will be
damaged, and stitch skipping
occurs. If it is too low, the needle
points will be crushed.
o If the clearance between the
needle guard
C
and the needles
is too large, the double chain
looper blade point will come in
contact with the needles, causing
the breakage of the needles,
causing the breakage of the
needles or looper blade point.
No clearance left between them
will cause them to come in exces-
sively close contact with each other,
and bend of needle, wear on the
needle guard and scratches on the
needles will occur.
o Excessive clearance left be-
tween the needle guard
D
and
the needles will cause stitch skip-
ping due to needle shake, and
insufficient clearance will cause
the needle guards to catch the
needles between them, leading
to wear on the needle guards
and scratches on the needles.
Adjustment Procedure Results of Improper Adjustment