Leibinger JET2 neo, Manual

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Page 52 Operation
– Elements and procedures
Group 6
Release R1.12 en JET2 neo
6.2.3 Drop charging
In order to be able to charge the drops it is necessary for the ink to have electrical
conductivity. This is possible through the use of specific salts that dissociate in the solvent
used. The drop brake-off point of the modulated jet is automatically set in such a manner
that this happens inside the charging electrode.
The drops can now be charged up by creation of voltage between jet and charging
electrode, because they are given a negative charge through the charge shift resulting in
the charge electrode gap. A specific charge voltage is clearly allocated for each drop
charge.
6.2.4 Drop deflection
After the drops have left the charging electrode they fly through an electrical field. Here,
those droplets that were previously charged in the charging electrode are deflected. The
drops that have not been charged fly straight ahead into the gutter. Here they are sucked
up and fed back to the circular flow of ink. The charged drops are only deflected in one
direction, the other direction is performed by the product to be inscribed.
6.2.5 Creation of a character
Each character is defined by a two-dimensional matrix, e.g. 7 x 5. An ink drop can be
assigned to every point of intersection. The character is formed by deflecting the ink drops
in a vertical direction and by moving the product which is to be imprinted horizontally. The
ink drops which are not to be positioned are not given electrostatic charges in the charging
electrode, and pass through the electrical field without being deflected and on into the
gutter tube. The controller (CPU) of the printer calculates the values which are required
for the generation of charging voltages of the single characters.