–
50
–
Standard Adjustment
Results of lmproper Adjustment
(1) Loosen setscrew
!0
in the needle bar bracket and adjust the height
of the needle bar.
(2) After adjusting the height of the needle bar, adjust clearances
C
provided between needles
8
and needle holes
9
in the throat
plate to equal and fix the needle bar with setscrew
!0
.
*
Refer to 5.- (9) Height of the needle.
1. Standard position of the rear needle guard
It is the standard that the lateral position of rear needle guard
1
is
the position where the rear needle guard receives the needle in the
range of
B
in the illustration.
2. It is the standard that the ridge line of rear needle guard
1
enters
in the eyelet of right needle (section
A
) when the needle bar is in
the lowest position.
3. When the top end of looper
3
comes from the extreme right position
to the center of right needle, the clearance provided between the
right needle and the top end of looper
3
becomes 0 to 0.05 mm
and the pressing amount of the top end of the needle becomes 0.1
to 0.2 mm.
It is the standard for the middle needle that when the top end of
looper
3
comes to the center of middle needle, the clearance
provided between middle needle and the top end of looper
3
becomes 0 to 0.05 mm and the pressing amount of the top end of
needle is such an amount that the rear needle guard touches the
middle needle.
*
For the details, refer to the standard adjustment procedure in 5.-
(11) Adjusting the needle guard.
™
When the position of the height of the
needle bar is excessively different,
stitch skipping, needle breakage,
thread breakage, etc. will be caused.
™
When the adjustment value is
excessively different from the specified
value, needle breakage or stitch
skipping will be caused.
