16
(A)
(B)
Guide line
The upper knife timing is the same as that of the needle bar. In fact, when the needle bar is at the highest position, the
upper knife should be also at the highest position.
To adjust the timing of the needle and the upper knife
To check:
1. Turn the handwheel toward you.
2. Check if the upper knife is also at the highest position
when the needle bar is at the highest position.
If not, adjust as follows.
Setscrew
Setscrew
To adjust:
1. Open the side cover.
2. Set the needle bar to the highest position by turning
the handwheel toward you.
3. Loosen the setscrews (2 pcs.). Turn the upper knife
drive cam to adjust the timing. Tighten the setscrews (2
pcs.).
When the upper knife timing is late:
Turn the upper knife drive cam to the direction (A).
When the upper knife timing is early:
Turn the upper knife drive cam to the direction (B).
NOTE:
Make sure the guide line on the edge surface of the
upper drive cam and the guide line on the main shaft are
matched.
Loosen the setscrews (2 pcs.) and push the upper knife
drive cam to check the guide line on the main shaft.
4. Turn the handwheel toward you to check the timing of
the needle and the upper knife again.
5. Close the side cover.
Needle
Upper knife
Highest position
of the needle
Highest position
of the upper knife
Upper knife drive cam
Mechanical Adjustment
MODEL: AirThread 2000D
