JUKI LK-1900B series Engineer's Manual

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(4) Crank balancer positioning
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the
sewing machine.
Standard adjustment
[Rotating direction]
When the needle bar
❸
lowers and the clearance between the needle bar connecting
❹
and the needle
bar bushing, lower
❺
is 5.7 mm(LK-1903B,1903BN:4.6mm), the two setscrews
❼
of the crank balanc-
er
❻
assume the horizontal condition.
[Axialdirection]
Keep the close contact with the main shaft eccentric cam
❽
and the crank balancer
❻
.
(5) Lower shaft backlash adjustment and connection/disconnection
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the
sewing machine.
Standard adjustment
1. Size of lower shaft backlash is 0.1 mm at the tip of the driver
❺
.Theshaftisrequiredtorotatesmooth-
ly.
2.Denethestoppositionofthelowershaft
❻
so that the setscrew
❼
settles almost in the center of the
atsection
❽
of the lower shaft
❻
.
0.1 mm or less
Face A
5.7 mm
(LK-1903B : 4.6 mm)
❶
❷

JUKI LK-1900B series Specifications

General

Brand	JUKI
Model	LK-1900B series
Category	Sewing Machine
Language	English