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Adjustment Procedures
Results of Improper Adjustment
Adjustment Procedures
Results of Improper Adjustment
1) Turn the handle until the needle guide claws are brought to the
position where they start closing.
2) Loosen four setscrews
B
, turn the tubular cam of the needle bar
guide (reference value : 86˚), and adjust so that the needle guide
claws completely close at the position of 0.8 to 0.5 mm before the
lower needle bar reaches its lower fixed position.
* When the needle guide claws are closed, check that the guide
claws have no play by moving the guide claws back and forth
by hand.
™
If the clearance is large :
The thread does not enter the
thread path guide, causing thread
breakage.
™
If the clearance is small :
The thread path guide comes in
contact with the support cylinder of
the lower needle bar, causing
thread path guide breakage.
™
If the timing shifts, the needle guide
comes in contact with the needle
bar or the needle guide does not
catch the thread.
Loosen setscrew
A
and adjust so that the edge of the thread path
guide is within 0.5 mm away from the upper position of the center of
needle. Then adjust so that a 0.3 to 1.0 mm clearance is obtained
between the thread path guide and the support cylinder of the lower
needle bar. After making the adjustment, tighten setscrew
A
.
Check that the thread passes inside of the thread path guide (side
B
) when the thread comes off the drum.
