Longitudinal Position Of The Blade Point Of Lower Knife; Adjusting The Height Of The Lower Knife - JUKI MF-7900 Series Engineer's Manual

4) Longitudinal position of the blade point of lower knife

❷
0.4 ± 0.2 mm

5) Adjusting the height of the lower knife

0 to 0.1 mm
❷
❶
❷
❶
❸
❶
❸
❹
– 160 –
1. Bring the needle bar to its highest
position.
2. Adjust so that the clearance be-
tween the blade point of lower knife
❶ and the front end face in the
thickness direction of the looper ❷
is 0.4 ± 0.2 mm when the distance
between the blade point of lower
knife ❶ and the center of needle
bar is 24 ± 0.5 mm.
Loosen nut ❸ , move the lower
3.
knife holder ❹ back and forth, and
adjust the position of the blade point
of lower knife ❶ .
After the adjustment, tighten nut ❸ .
4.
(Caution)
❹
1. Bring the needle bar to its highest position.
2. When operating the air cylinder to the right di-
rection, the lower knife ❶ is projected to the left
direction.
Loosen setscrew ❹ of guide ❸ , move the
3.
guide ❸ up and down so that the clearance
between the under surface of lower knife ❶ and
the top surface of looper ❷ is 0 to 0.1 mm.
After the adjustment, tighten setscrew ❹ ,
4.
and make sure that the thread trimmer device
moves smoothly by operating manually the air
cylinder.
(Caution) Perform the work with the needle bar at
the highest position when actuating the
thread trimmer mechanism by hand.
1. Perform the work with
the needle bar at the
highest position when
actuating the thread
trimmer mechanism by
hand.
2. After the adjustment,
actuate plunger by
hand and confirm that
the thread trimmer de-
vice smoothly works.