Crank Balancer Positioning; Lower Shaft Backlash Adjustment And Connection/Disconnection - JUKI LK-1900AN Engineer's Manual

(5) Crank balancer positioning

[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

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 .
Standard adjustment
Standard adjustment
Face A
– 12 –
0.1 mm or less