Hitachi UX Twin Nozzle - Faults - no Indication on Screen

6-82
6.5 Faults – No indication on screen
6.5.1 Chipped print (lower dots)
Direction of
deflection
Missing dots
Gutter
Ink/foreign
matter
Print
drop
Chipped print
Replace the ink.
Adjust the ink stream
position so that the ink
stream is centered with
respect to the gutter.
No
Is the ink stream
positioned at the
center of the gutter?
Yes
Is the ink pressure
higher than the
specified limit?
No
Yes
Has the operating
time exceeded the ink
shelf life?
No
Yes
Resume the
operation.
Sprinkle the makeup
over the gutter edge
section to clean it.
Is there ink or dirt
buildup on top of the
gutter edge section?
Yes
No
Adjust the charge voltage.
Yes
Is the charge
voltage properly
adjusted?
No
Adjust the ink
pressure until it is
within the limits.
Can the ink pressure be
adjusted?
No
Yes
Provide pressure relief,
then replace the
pressure-reducing valve.
[Caution]
1. If the ink stream does not enter into the center of the gutter, the dot
with small amount of deflection will hit the gutter inlet and will not go
out of the printhead.
Since this may cause a missing dot, set the ink stream at the center of
the gutter to prevent this problem.
2. If the ink pressure is high, the ink ejection speed becomes faster and the
amount of the deflection becomes small. When this dot with small
deflection hits the gutter, a dot missing will occur.
To prevent this problem, set the ink pressure within the range specified.