JUKI lbh-1790 series Engineer's Manual page 31

Adjustment Procedures
1. Loosen four setscrews 2 in the presser lifter motor, put a sheet
of thin paper (approximately 0.05 mm thick) between gear,
large 3 and gear, small 4, close the play, and fix four
setscrews 2 in the presser lifter motor to almost adjust the
backlash.
2. After adjusting the backlash, apply grease to gear section of
gear, large 3 and gear, small 4.
Loosen setscrew 1 in the presser bar position bracket when the
presser is in the lowest position and adjust so that the height
between presser bar position bracket 2 and the work plane of
the machine arm is 8 mm. Then tighten setscrew 1 in the presser
bar position bracket.
Results of Improper Adjustment
™ When backlash is large, presser
f o o t l i f t i n g w o r k i n g n o i s e
increases.
™ W h e n b a c k l a s h i s s m a l l ,
b a c k l a s h i s c l o s e d a n d
malfunction occurs.
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