Hitachi PB - 1 Problems Due to Inappropriate Ink Beam Position in Charged Electrode; Miscellaneous

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6.6Miscellaneous
6.6.1 Problems due to inappropriate ink beam position in charged
electrode
● If the ink beam does not pass through the charged electrode, the following
problems may occur:
① The height of printed characters will be larger than standard
② Since the ink particles are not charged normally:
・The character quality will degrade (characters are distorted).
・Print fault, such as appearance of crushed characters, will occur.
③ Since the amount of charge on particles that are slightly charged for auto
phase detection among the dots not used for printing is abnormal, those
particles will be excessively deflected by the deflecting field and cannot
enter the gutter hole. Therefore, the gutter will be dirty, causing an
alarm of either excessive electrical charge or no electrical charge.
● Check the ink beam passing position in charge electrode, and adjust the
electrode so that the ink beam passes through its center.
● Adjustment procedure:
① Loosen the screw holding the charge electrode, use the slight clearance to
change the position of electrode, and then tighten the screw.
② Use small pliers to apply force to the bent portion of charge electrode for
correction.
Good
Nozzle
Ink
beam
Charge
electrod
Center
Closer
Beam drifts to one side.
Closer
Beam is oblique