JUKI LK-1900AN, Engineer'S Manual, Page: 24 / 140

– 12 –
(5) Crank balancer positioning
Standard adjustment
[Rotating direction]
When the needle bar
3
lowers and the clearance between the needle bar connecting
4
and the needle
bar bushing, lower
5
is 5.7 mm (LK-1903AN: 4.6 mm), the two set screws
7
of the crank balancer
6
as-
sume the horizontal condition.
[Axial direction]
Keep the close contact with the main shaft eccentric cam
8
and the crank balancer
6
.
(6) Lower shaft backlash adjustment and connection/disconnection
Standard adjustment
1. Size of lower shaft backlash is 0.1 mm at the tip of the driver
5
. The shaft is required to rotate
smoothly.
2. Define the stop position of the lower shaft
6
so that the set screw
7
settles almost in the center of
the flat section
8
of the lower shaft
6
.
0.1 mm or less
Face A
5.7mm
(LK-1903AN: 4.6mm)