Troubles And Corrective Measures; Mechanical Parts - JUKI LK-1900AN Engineer's Manual

11. Troubles and corrective measures

(1) Mechanical parts

Trouble
1. Wiper cannot spread a thread.
2. Abnormal noise
3. Deformation in sewn patterns
To the next page
Cause (1)
1-1) Interference between wiper
and needle
1-2) Displacement of front-rear
wiper position
1-3) Thread holding before
wiper action
2-1) Backlash between the
oscillator and the shuttle
driver shaft is large.
2-2) Too much clearance between
inner hook and shuttle driver
3-1) Too much backlash in the
Y feed gear
3-2) Too much backlash in the
X feed gear
3-3) Travelling torque in X di-
rection is excessive.
3-4) Travelling torque in Y direc-
tion is excessive.
To the next page
Cause (2)
1-A) Wiper mounting position is inad-
equate.
2-A) Wiper mounting position is inad-
equate.
3-A) The right left wiper mounting po-
sition is inadequate (insufficient
distance to the needle).
1-A) Backlash is too much in the Y
feed arm and the motor base.
1-B) Backlash is too much in the Y feed
pulse motor and the motor base.
3-A) The motor is pressed against the
X feed arm too strongly.
3-B) The feed plate or the work clamp
foot is caught by the needle hole
guide.
4-A) The pulse motor is pressed against
the Y feed shaft too strongly.
Check and corrective measures
Adjust the wiper position.
Adjust the wiper position.
Adjust the wiper position.
Check oscillator gear positioning and adjust
the lower shaft gear backlash.
Adjust the clearance between inner hook
and shuttle driver
Adjust backlash of motor base.
Adjust backlash of Y feed pulse motor.
Adjust backlash of the X feed gear.
Adjust backlash of the motor.
Tighten the set screw further for the needle
hole guide.
Adjust backlash of the feed motor gear.