JUKI DDL-9000A Engineer's Manual page 15

Adjustment Procedure
[Feed locus change]
By adjusting the phase of the vertical feed cam
the up/down timing for the feed locus and needle.
Adjustments can be carried out with two setscrews
1. Timing standard
The vertical feed shaft engraved marker line
vertical feed cam engraved marker line
Refer to [3.-(3) Needle and feed timing].
2. Timing fast
If you adjust the vertical feed shaft engraved marker line
vertical feed cam engraved marker line
vertical feed timing is hastened against horizontal feed.
(Also hastened against the needle)
(Cautions) Adjustments should be done within –20
graduations).
3. Timing slow
If you adjust the vertical feed shaft engraved marker line
vertical feed cam engraved marker line
vertical feed timing is delayed against horizontal feed.
(Also delayed against the needle)
(Cautions) Adjustments should be done within +20
graduations).
(Cautions) 1. When timing of the vertical feed cam
the feed timing is also changed against the needle.
When the timing is adjusted, re-adjustment is
required in accordance with [(3) Needle and feed
timing].
2. The angle of the engraved marker line graduation 1
denotes 10
, it is possible to change
at 0°.
and the minus side, the
and the plus side, the
°
.
.
coincides with the
to the
°
(2
to the
°
(2
is changed,
– 11 –
Results of Improper Adjustment
o When tightening the two setscrews
of the vertical feed cam
work should be done while a good
centering is secured.
Otherwise, there will be adverse
torque or unusual sound generation,
or abnormal wear may be caused.
o Since the motion in horizontal
direction is reduced at the
beginning of feeding, the material
cloth is fed assuredly by the effect
of creep reduction.
o Feeding force is reduced around
the end of feeding because the
feed dog lowers faster.
o The motion becomes moderate at
the beginning of feeding, thus
making the material cloth biting
worse.
o Light materials tend to be less
damaged.
o The material cloth is fed assuredly
at the end of feeding. Thanks to
the leading effect, puckering tends
to be improved.
, this