– 108 –
❸
0.05 to 0.1 mm
❷
❶
1.5 mm
2.3 mm
❹
❺
❸
Hook driving shaft
setting collar
The hook driving shaft setting
collar is aligned with the end
face of hook driving shaft C
Right hook
Hook driving shaft D
Hook driving shaft
setting collar
The hook driving shaft
setting collar is aligned
with the end face of hook driving shaft D
Hook driving shaft C
Left hook
8-2. Adjusting the timing between the needle and the blade point of hook
1) Place the sewing machine into the hook adjustment mode.
2) Loosen lower shaft setting collar clamp screw
❸
and hook driving shaft saddle setscrews
❹
and
❺
mounted on the top surface of bed. Then, turn the handwheel counterclockwise to lift the needle bar by 2.3
mm from its lower end.
(The needle bar goes up by 2.3 mm by advancing the rotation angle of main shaft by 25° from the value
indicated on the main shaft rotation angle display when the needle bar rests at its lowest point.)
3) In the state described in 2), align hook blade point
❶
with the center of needle
❷
, and change the po-
sition of hook driving shaft saddle to the right and left so that a clearance of 0.05 to 0.1 mm is provided
between the hook blade point and the needle. Then, firstly tighten setscrews
❹
and
❺
first, and sec
-
ondly tighten lower shaft setting collar clamp screw
❸
.
At this time, a clearance of 1.5 mm is provided between the blade point of the hook and the top end of
the needle eyelet. (The hook driving shaft setting collar must be aligned with the end face of hook driv-
ing shaft C and D.)
