4
22 ± 0.5 mm
!4
!3
!3
center of needle
bar
!2
4
– 10 –
6. Initial position of the looper
thread trimmer mechanism
When the lower knife 4 is located at its leftmost posi-
tion, the top end of the lower knife 4 has to be spaced
22 ± 0.5 mm from the center of needle bar.
7. adjusting the stopper
Adjust the position of stopper !4 so that a clearance of
0.3 to 1 mm is provided between looper !3 and clamp
pressure adjusting spring !2 when the counter knife is
located at its leftmost position (forward end).
8. adjusting the height of the
lower knife
When the needle bar advances from its upper dead
point by 15º, the clearance of 0 to 0.1 mm has to be
provided between the under surface of lower knife 4
and the top surface of looper !3 .
Perform the work with the needle bar at the
highest position when actuating the thread
trimmer mechanism by hand.