JUKI LK-1900AN Engineer's Manual page 27

Adjustment procedures
1. Loosen the two set screws 5 and increase the backlash of the
lower shaft gear 3 .
(Caution) If the lower shaft gear 3 has insufficient backlash,
the oscillator 2 does not swing correctly. In such a
case, refer to "(6) Lower shaft backlash adjustment
and connection/disconnection" and provide a suf-
ficient backlash.
2. The two set screws 1 and the two set screws 7 should have
been loosened in advance. In this case, the second screw of
the set screws 1 and 7 should be loosened first. Then, the
first one can be loosened.
3. Adjust the clearance to 8.5 to 9.0 mm between the oscillator 2
and the frame, and decide the positioning of the oscillator 2 .
4. Tighten the two set screws 7 and then fix them so that the
oscillator 2 is not displaced.
(Tighten the first screw first so that it comes in contact flatly
with the oscillator shaft 4 . Then, tighten the second one.)
5. Tighten the two set screws 1 and fix the oscillator arm 6 .
(Tighten the first screw first so that it comes in contact flatly
with the oscillator shaft 4 . Then, tighten the second one.)
6. Refer to "(4) Crank connecting rod connection/disconnection"
and decide the positioning of the crank rod.
7. Make backlash adjustment for the lower shaft gear 3 , accord-
ing to "(6) Lower shaft backlash adjustment and connection/
disconnection."
(Caution) 1. In the case of disassembly and adjustment,
grease up treatment is always needed for the
specified places (2 positions) and the gear
area A of the oscillator 2 .
2. When the crank rod (under-cam) is removed,
actions for oscillator gear positioning must be
taken, without fail.
Refer to "(4) Crank connecting rod connection/
disconnection."
Adjustment procedures
1. Loosen the set screw 1 and remove it.
2. When the adjusting screw 2 is tightened, the quantity of oil
can be regulated for the lubrication pipe left 4 .
3. After adjustments, tighten the set screw 1 to fix it.
(Caution) 1. In the state of standard shipping, the hook lu-
brication reducer 3 is positioned so that it is
lightly tightened and then return-loosened by 4
turns.
2. When reducing the oil amount, the screw
should not be tightened up fully. Tighten the
hook lubrication reducer 3 and then return
it by two turns. In this position, wait for half a
day to see how it goes. Too much reduction
can be a cause of hook wear.
Results of Improper adjustment
If the position for fixing the oscil-
o
lator 2 is inadequate, this can
also be a cause of the frictional
wear or lock-up of the oscillator
pin, crank rod lid, under cam,
and the crank rod.
Results of Improper adjustment
If the amount of hook lubricant
o
is reduced too much, this can be
a cause of frictional wear of the
hook race plane or lock-up.
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