JUKI MEB-3200 Engineer's Manual page 41

Adjustment Procedures
Remove the knife cover and adjust following the procedure below.
(Position of the looper thread guide plate and inclination of the
counter knife)
1. Loosen two setscrews 2.
2. Turn moving knife 3 in the direction of the arrow mark A and
adjust the position of looper thread guide plate 1 so that the
slot end corner on the lower side of moving knife 3 is aligned
with the corner on the lower side of looper thread guide plate
1.
3. Turn moving knife 3 in the direction of the arrow mark A and
adjust the position of counter knife 4 so that there is no
clearance in the engagement section and they come in uniform
contact with each other before or after the corner of the blade
of moving knife 3 is aligned with the top end of counter knife
4.
4. Arrange counter knife auxiliary spring, upper 6 and counter
knife auxiliary spring, lower 7 with counter knife 4. (The convex
side of counter kife auxiliary spring, lower 7 is on the side of
counter knife 4.)
5. Tighten two setscrews 2 to fix the counter knife.
(Caution) When removing or loosening the setscrew of
moving knife 3, the position of moving knife 3 may
change. In this case, perform the adjustment of the
clearance of the looper thread guide plate as descrived in
the aforementioned steps.
(Moving knife pin)
1. Be sure to confirm that moving knife pin 5 protrudes 1.8 to 2
mm in the direction of the rear face of moving knife 3.
Results of Improper Adjustment
™ If counter knife 4 comes in one-
sided contact with the moving
knife, thread trimming failure
such as end thread remaining,
thread cutting failure, etc. will
occur. As a result, one-sided
worn-out of the blade or blade
breakage will be caused.
(Caution) If there is a clearance
i n t h e c e n t e r o f t h e
engagement section, it is
necessary to sharpen the
blade.
™ If looper thread guide plate 1 is
located excessively upward, the
top end rubs against the slot of
moving knife 3. As a result,
damage of parts will be caused.
In addition, it comes in contact
with the knife cover. As a result,
malfunction will occur.
™ If looper thread guide plate 1 is
located excessively downward,
looper thread of sewing start
cannot be made free and the
thread is cut. As a result, thread
waste is increased.
™ If the protruding amount of
moving knife pin 5 is large, the
pin interferes with section B of
presser plate, right 8. As a
result, malfunction or parts
breakage will be caused.
™ If the protruding amount of
moving knife pin 5 is small,
looper thread of sewing start is
c u t a n d t h r e a d w a s t e i s
increased.
(In the case where the sewing
length is long, moving knife pin
5 cannot make free the looper
thread of sewing start.)
37
− −