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7-4. Adjustment of the picker
The picker device is used in order to stabilize idling
of the bobbin at the time of thread trimming.
7-4-1. Checking the standard adjustment
1) Check to make sure that the power switch is in
the "OFF" state. Tilt the sewing machine.
2) Bring thread trimming solenoid
❶
in the pull-in
state by hand.
3) In this state, the standard adjustment value of the
clearance between picker link
❸
and picker arm
❹
is 0.5 mm. At this time, a clearance of 0 to 0.3
mm is provided between bobbin
❺
and picker
❻
.
1. If there is no clearance between bobbin
❺
and the tip of picker
❻
, picker
❻
strongly press
bobbin
❺
. As a result, the bobbin fails to supply a required length of bobbin thread at the
time of thread trimming. In this case, the bobbin thread is likely to be trimmed short and
thread slip-off at the beginning of sewing is likely to occur.
2. If there is an excessively large clearance between bobbin
❺
and the tip of picker
❻
, thread
required for thread trimming may slip off the tip of picker and the length of needle thread
remaining at the needle tip after thread trimming will be short. In addition, bobbin
❺
is
likely to idle frequently at the time of thread trimming causing problems at the beginning of
sewing.
When it is necessary to check how the
picker is adjusted, install the bobbin
case and bobbin in the hook first, then
check the picker.
(0.5 mm)
To be in contact
Once the standard adjustment is carried
out correctly, there is a slot-shape space in
picker link
❸
to allow the picker to make a
necessary returning action (damper function).
0 to 0.3 mm
❼
❸
❺
❻
❹
❻
❻
In the standard
adjustment state
of the picker, the
center of picker
❻
is almost aligned
with the center of
U-shape section of
bobbin case.
❶
❷
❸
❻
❸
❹
7-4-2. Standard adjustment
1) Loosen picker link pin nut
❷
(9 mm). Carry out adjustment by moving picker link
❸
to the right and left.
2) After the adjustment, tighten picker link pin nut
❷
.
7-4-3. Standard adjustment (Adjustment at the tip position)
1) Loosen picker setscrews
❼
(two pieces). Adjust the position of picker.
2) After the adjustment, tighten picker setscrews
❼
(two pieces).
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the
sewing machine.