Computerized Control System for Square Buttonhole Machine Preparation before Sewing
9
2.4
Threading at Bobbin
In order to avoid the personal injury caused by the sudden start of
machine, user has to turn off power and make sure the motor stops
before performing the following operation
1
）
Install the shuttle core into the case in the direction of the arrow
；
2
）
Thread the thread through the threading open
①
and then pass the spring
②
, then go through the open
③
.
Finally, pull the thread from the slot
④
.
※
Attention: The threading method at slot
④
in straight buttonhole sewing is different from
that of zigzag buttonhole.
2.5
Adjustment of Bobbin Thread Tension
In order to avoid the personal injury caused by the sudden start of
machine, user has to turn off power and make sure the motor stops
before performing the following operation
