– 15 –
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
6. Adjusting the engagement between the
knives
1) Adjusting the position of the moving knife and
counter knife
The standard initial position of moving knife
❶
is 5 mm from the center of needle. The stan-
dard initial position of counter knife
❷
is 5 mm
from the center of needle.
Loosen screw
C
and adjust the position of the
knives.
2) Adjusting the forward travel amount of the mov-
ing knife
When you turn the handwheel in the reverse
direction while pushing the cylinder of thread
trimming solenoid, moving knife
❶
is rotated
by the thread trimming cam. At this time, adjust
the position of moving knife
❶
so that its end
portion moves away from the end portion of
counter knife
❷
by 1.0 to 1.5 mm when the
forward travel amount of moving knife
❶
is
maximized. (Standard installation position)
❷
❶
Counter knife
Counter
knife
Counter knife
5 mm
1 to 1.5 mm
5 mm
3 mm
3 mm
B
A
C
Moving
knife
Moving
knife
Moving knife
Feed dog
❶
, hook
❷
and pump
❸
should be
periodically cleaned.
4-11. Periodical cleaning of the sewing machine
❶
❷
❷
❸
3) Adjusting the counter knife pressure
A. The standard adjustment position of the knives is achieved when the moving knife and counter
knife come in light contact with each other, as shown in the figure.
B. Especially when using thick threads, the knives cannot trim them sharply. In this case, increase
the pressure applied to the counter knife.
C. To adjust the pressure applied to the counter knife, loosen locknut
B
with a box wrench and ad-
just the pressure applied to the counter knife with screw
A
.
After the completion of adjustment, tighten locknut
B
.
