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(8) Adjusting the timing relation between the looper and needle bar
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the
sewing machine.
Standard adjustment
1. Timing relation between the looper and the needle bar (synchronization)
It is the standard that dimension
A
is the same as dimension
B
when the needle bar goes up from
the lower dead point, the blade point of looper passes the rear of needle, and the left end of right nee-
dle aligns with the blade point of looper, and when the needle bar comes down from the upper dead
point, the blade point of looper passes the front of needle, and the right end of right needle aligns with
the blade point of looper.
(Looper timing is more advanced by a piece of needle than the needle bar timing.)
Going of looper
Returning of looper
