Conducting liquid e.g. ink, drops selective charging device for ink jet print head, has charge electrode and air gap, at constant potential, to transfer charge to jet sections, where electrode is provided downstream gap along jet path

摘要

The device has an ejection nozzle (4) to eject a liquid in the form of a continuous jet (14). An electric signal is applied on a piezoelectric actuator to generate jet sections, where a jet shatter point (B) is at same distance from the nozzle for each section. An air gap (20) and a charge electrode (22) are carried at a constant potential to transfer an electric charge to each section, where the transfer is different based on the sections` lengths. The gap extends over a thickness along the path of the jet from the point, and the electrode is provided downstream the gap along the path. Independent claims are also included for the following: (1) a method for selectively charging the drops (2) a method for inkjet printing.