JUKI AMS-221EN Series Engineer's Manual page 73

Adjustment Procedures
1. If the dimensions of 0.3 x 8mm are not secured, retouching is re-
quired with the aid of an oil stone.
Dimension A
Part No.
(mm)
0.8 14103253
1.3 14103352
1.7 14103659
1.9 B1817210DAD Shuttle race ring D
Adjustment Procedures
1) Stroke adjustment
Loosen the setscrew
Turning it clockwise increases the movable distance and thread draw-
ing amount.
2) Adjustment of thread take-up spring tension
Turn the thread tension post
tightened to adjust the thread take-up spring
it clockwise increases the thread take-up spring
it counterclockwise decreases the tension.
(Caution) Set the stroke of the thread take-up spring
for thin threads with thread number #50 or higher.
Name of part
Shuttle race ring A
Shuttle race ring B
Shuttle race ring C
, and turn the thread tension assembly
using a thin driver with the setscrew
Remarks
Optional
Standard
Optional
Optional
o If the stroke of the thread take-up
.
o If the stroke of the thread take-up
tension. Turning
tension, and turn
shorter
(Caution)
If the thread take-up spring
interferes with the L-shaped
thread guide
up spring
the initial position before thread
trimming, and the length of re-
maining needle thread may be
short. If such a trouble occurs,
bend the section
take-up spring
clearance
– 69 –
Results of Improper Adjustment
Results of Improper Adjustment
spring is larger than the specified
value:
Length of remaining needle
thread is shortened, causing the
needle thread to slip off the needle
at the sewing start.
spring is smaller than the speci-
fied value:
Needle thread breakage will oc-
cur at the time of thread trimming
when using a thin thread.
, the thread take-
may fail to return to
of the thread
C C C C C
to widen the
.
B B B B B