Inkjet printer operating a binary continuous-jet with optimum deflection and maximised print speed

An ink jet printer comprising:

• at least one electrical pulse signal generator;
• a drop generator comprising
• at least one ink ejection nozzle which receives ink under pressure from a stimulation chamber in hydraulic communication with the nozzle at least one ejection nozzle;
• and
• at least one flexible element, the deformation of which by an electromechanical actuator supplied electrically by the at least one pulse signal generator, modulates a volume of the stimulation chamber to break a continuous ink jet emitted along an axis Z of each said ejection nozzle into segments;
• and
• a block of electrodes offset with respect to the axis Z of each said ejection nozzle and comprising at least two deflection electrodes, said at least two deflection electrodes being nearest from the nozzle and of an individual height He separated from each other by a dielectric of height Hd,
• in which, in a printing operation
• the at least two deflection electrodes are adapted to receive signals in phase opposition, and
• the drop generator is configured to output to the electromechanical actuator calibrated pulses in which
• a first period less than or equal to Tc1 creating first jet segments each having a length less than or equal to a first length hC1 less than the height Hd of the dielectric so that said first jet segments are deviated with a minimum amplitude by the at least two deflection electrodes in response to the signals in opposition phase and,
• a second period Tc3 creating second jet segments individually alternately with the first jet segments and of a length less than or equal to hc1, said second jet segments each having a second length hc3 substantially equal to 2*[(1+α)He+Hd] so that said second jet segments are deviated with a maximum amplitude, α, being a coefficient correction dependent of an extension of an electrostatic field on each side of an electrode and of the capillary forces in the second jet segments over a height of the block.