Hitachi IJ PH Service Manual page 181

6.5.2 Chipped print (upper dots)
No
Adjust the ink stream
position so that the ink
stream is centered with
respect to the gutter.
No
Since it is conceivable that the
ink flow path may be clogged,
clean the ink final filter and
joints, backwash the nozzle,
and disassemble and clean the
nozzle.
Yes
Can normal
prints be made?
No
Replace the ink.
Yes
Pour the intensifier over
the deflection electrode to
clean it.
No
Adjust the charge voltage.
NOTICE
Do not repeat the nozzle backwash procedure more than two times.
If it is repeated to an excess, the ink becomes thin, thereby
causing disordered prints. If the ink is thin and disordered
prints are encountered, replace the ink.
Chipped print
Is the ink stream
positioned at the
center of the gutter?
Yes
Is the ink pressure
Yes
lower than the
specified limit?
No
Is it possible to make
normal prints with the
ink pressure raised
above the specified
limit?
Provide pressure relief and
Yes
then replace the pressure-
reducing valve.
Is there any ink or dirt
buildup on the plus
deflection electrode?
No
Is the charge
voltage properly
adjusted?
Yes
Resume the
operation.
6-44
Direction of
deflection
Can the ink pressure be
Yes
adjusted?
No
Adjust the ink pressure
until it is within the l
imits.
Missing
dots