Hitachi UX Twin Nozzle Service Manual page 334

6.5.10 Problems due to inappropriate ink stream position in charged
electrode
If the ink stream does not pass through the center of charge electrode, the problems
>
bellow may occur:
(1) The height of printed characters may become larger than the standard height.
(2) Since the ink drops are not charged normally:
- The print quality may be degraded (distorted characters).
- Print fault such as crashed character or character distortion may occur.
(3) There are ink drops for auto-phase detection among the drops which are not
used for printing. These ink drops for auto-phase detection are slightly
charged but may not be deflected correctly by the deflection electrode. As the
result, the ink drop cannot be caught into the gutter hole, stick to the gutter
and cause alarm of "Ink Drop Charge Too High" or "No Ink Drop Charge".
> Check the ink stream passing position through charge electrode and adjust the
electrode's position so that the ink stream passes through its center.
> Adjustment procedures:
Loosen the screws(2pcs) fixing the charge electrode, use the slight clearance to
change the position of electrode, and then tighten the screws.
Good
Nozzle
Charge
Ink
electrode
stream
Center
Closer
Ink stream drifts to one side.
6-92
Closer
Ink stream is oblique