If the main shaft eccentric cam
is not secured, the main shaft eccentric
cam
should be positioned first.
1. Loosen 2 set screws
securing the crank balancer
.
2. Remove 4 set screws
, then remove the crank rod cover
.
3. Turn the main shaft in the forward direction
A
so that the needle bar
lowers and the clearance between the needle bar connecting
and needle bar lower bushing
is 4.6 mm.
4. Secure the crank balancer
with 2 set screws
under the condi-
tions that 2 set screws
securing the balancer
are horizontally
positioned and the balancer
is moved in the direction of Arrow
B
to make it into contact with the main shaft eccentric cam
. For
tightening 2 set screws
, tighten them alternately.
– 12 –
Adjustment Procedures
Results of Improper Adjustment
o If the mounting angle of the crank
balancer
is wrong, vibration
during sewing will be intensified.
o If the sewing machine is used for
a long time under the condition of
wrong securing position, the life
of main shaft bearing may be
shortened.
o If the crank balancer
is not
moved in the direction of Arrow
B
, it may interfere with the sew-
ing machine frame.