JUKI MF-7800D Series, Руководство инженера

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1. Loosen setscrews in the looper thread cam and adjust while
checking that looper thread comes off from the periphery of the looper
thread cam.
(Caution) When setscrews in the looper thread cam are
loosened, looper thread cam moves in the shaft
direction as well.
Assemble so that the clearances provided between the
cam and the thread guide are equal.
2. Adjusting the looper thread winding prevention plate (former type)
Adjust the clearance provided between the top end of section
A
of
looper thread winding prevention plate and the edge of looper
thread cam to approximately 0 to 0.3 mm (looper thread winding
prevention plate has a slot at the section of setscrew and
moves as if it rotates making setscrew as the center), and tighten
setscrews and to fix the looper thread winding prevention plate.
3. Adjustment of the bobbin thread cam entanglement preventive cutter
(new type)
Adjust the clearances to 0.5 to 1mm between the tip of bobbin thread
entanglement preventive cutter and metal cover and between
the end plane of cutter and that of bobbin thread cam . Tighten
setscrews to fix them.
o When the position of looper
thread cam slips greatly out
of position, stitch skipping or de-
fect of thread tightness on the
back of the looper is apt to
occur.
o It is effective to adjust as narrow
as possible the clearance
provided between the top end of
click section (section
A
) of looper
thread winding prevention plate
and the edge of looper thread cam
. However, when making them
come too near and come in
contact with each other, looper
thread cam is scratched and
w i n d i n g i s c a u s e d b y t h i s
adjustment, instead.
o The effect of thread entanglement
prevention becomes great if the
clearances are adjusted to a
minimum between the tip of
bobbin thread entanglement
preventive cutter and metal
cover and between the end
plane of cutter and that of
bobbin thread cam . However,
if these clearances are made too
small, collision of parts may occur
and bobbin thread cam and
metal cover may be damaged,
thus causing thread entanglement
on the contrary.
Adjustment Procedure Results of Improper Adjustment
Equal clearances