JUKI LU-2800 Series, Engineer'S Manual

Page: 31 / 143

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Adjustment procedures Results of Improper adjustment
2) Knee lifter (Without thread trimmer only)
1. Loosen setscrews of the face plate and the rear cover to re-
move the face plate and the rear cover.
2. Loosen clamping screw ❶ of the knee lifter connecting arm.
3. Adjust the lifting amount to 19 to 20 mm in the state that the
lifter plate ❸ is in contact with the spring receiving ❷ .
At this time, place a thing thickness of which is 20 mm between
the top surface of throat plate
❹
and the under surface of
presser foot ❺ to facilitate adjustment.
4. Move the knee lifter link C ❻ to the horizontal position in the
state of step 3, and tighten clamping screw ❶ of the knee lifter
connecting arm in the state that the knee lifter link C ❻ is in
contact with screw
❼
of the knee lifter connecting arm.
5. Remove the 20 mm thick thing placed between the top surface
of throat plate ❹ and the under surface of presser foot ❺ .
6. Attach the face plate and the rear cover.
7. Remove the knee press plate and tilt the machine arm.
8. Loosen stopper nut
❽ to adjust the lifting amount by screwing
amount of stopper screw
❾
.
To use the machine with the amount of alternate vertical move-
ment is set at 6.5 mm or more, adjust that the height from the
top surface of throat plate
❹ to the under surface of presser
foot ❺ is 16 ± 0.5 mm.
(Step 7. to 8. is standard gauge type only.)
(Caution) 1. Check to be sure that parts of the knee lifter
mechanism does not come in contact with the
frame and other parts around it when the knee
lifter link C
❻ is positioned horizontally.
If the knee lifter link C ❻ comes in contact with
the aforementioned parts, loosen the thrust col-
lar setscrews and adjust the lateral position of
the link.
2. Tighten clamping screw ❶ of the knee lifter con-
necting arm so that the knee lifter link C ❻ is no
lateral play.
3. For the standard gauge type machine, the walk-
ing foot interferes with the needle bar when the
amount of the alternating vertical movement of
the walking foot and the presser foot is set at
6.5 mm or more. To use the machine with the
amount of the alternating vertical movement is
set at 6.5 mm or more, set the lifting amount of
the knee lifter at 16 ± 0.5 mm.
When the lifting amount is higher
than the specified value :
o
The top end of the needle bar
interferes with the walking foot
and the walking foot may be
damaged when the presser foot
is raised.
When the lifting amount is lower
than the specified value :
o
The presser foot is not sufficient -
ly raised and the working prop-
erty may be deteriorated