Adjusting The Top Covering Thread Trimmer Mechanism; Adjusting The Engagement Of Knives; Adjusting The Pressure Of Clamp Spring; Adjusting The Position Of The Blade Point Of Moving Knife - JUKI MF-7500 Series Instruction Manual

VIII. ADJUSTING THE TOP COVERING THREAD TRIMMER MECHANISM
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest. In addition, cut the air
supply from air compressor.
❽
❶
❸
❷


❷
❾
❾
❹
❺
❼
❻

❷
Fig. A
1. Adjusting the engagement of
knives
1) Adjust so that the engagement of fixed knife ❶
with moving knife ❷ is 0.5 mm.
2) When adjusting the engagement, loosen setscrews
❹ and move knife holder ❺ up or down to adjust.
2. Adjusting the pressure of
clamp spring
1) Top covering thread is held with clamp spring ❸
after thread trimming.
2) Holding pressure can be adjusted by loosening nut
❻ and turning screw ❼ .
3) Holding pressure is increased when tightening
screw ❼ and it is decreased when loosening screw
❼ .
After the adjustment, tighten nut ❻ .
4)
5) Make the holding pressure as low as possible with-
in the range of holding the top covering thread.
3. Adjusting the position of the
blade point of moving knife
1) Bring the needle bar to its highest position.
2) When hinge screw ❽ is lowered, moving knife ❷
lowers together.
Adjust so that the hook of moving knife ❷ enters
3)
the recess in the top face of spreader ❾ to be
brought to the position where the moving knife
catches the top covering thread when moving knife
❷ is brought to the lowermost position. Then, tight-
en screws  ,  and  .
Adjust the moving knife vertically so that a clear-
ance of 0.5 mm is provided between the recess
section of spreader ❾ and the moving knife, and
laterally so that the moving knife ❷ is brought to
the center of the width of recess in spreader, as
illustrated in Figure A.
Screws  are for adjusting vertical position of the
4)
knife, screws  for adjusting lateral position of
the knife, and screws  for adjusting angle of the
knife.
Make sure that the moving knife does not in-
terfere with other components such as press-
er, needle, spreader, etc. within the working
range of moving knife ❷ .
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