JUKI LU-2800 Series, Руководство инженера

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Adjustment procedures Results of Improper adjustment
1. Set the stitch dial to “0”.
2. Turn the handwheel to bring the height of the feed dog
❸ to
the maximum. (Bring the needle bar to the lowest dead point of
its stroke.)
3. Loosen clamping screw
❶
of the vertical feed front arm.
4. Turn the vertical feed front arm ❷ to adjust the height of the
feed dog ❸ from top surface of the throat plate ❹ to the dimen-
sion A. Then securely tighten clamping screw ❶ of the vertical
feed front arm.
When the height of the feed dog ❸
is higher than the specified value :
o
Stitch pitch becomes larger than
the scale of the feed dial.
o
Balloon stitches will result.
o
Return of sewing product will
occur.
o
The feed dog ❸ comes in con-
tact with the knife, and the knife
and the feed dog
❸
may be
damaged.
When the height of the feed dog ❸
is lower than the specified value :
o
Stitch pitch becomes smaller
than the scale of the feed dial.
o Feed force will be deteriorated.
Adjustment procedures Results of Improper adjustment
1. Loosen two setscrews
❶
of the hook.
2. Draw out hook ❷ in the direction of the arrow.
3. Loosen four setscrews ❼ to remove the lubrication base ❻ .
4. Replace the washer ❸ to adjust so that the clearance between
throat plate ❹ and top surface of hook stopper section of hook
❷ is dimension A.
(Refer to "4. Selective parts and consumable parts" about the
types of washer
❸ .)
5. Align the notched section of hook shaft ❺ and No. 1 screw of
setscrews ❶ of the hook. Then tighten two setscrews ❶ of the
hook.
o
Stitch skipping or thread break-
age will result.
o
Needle breakage will result.
o
Irregular stitches will result.