Ink-jet printing method and device therefor

An ink-jet printing method of the type including the steps of imparting ultrasonic vibrations to the pressurized ink so as to cause the ink jet to emerge through a nozzle and break into a train of ink drops equally spaced apart from each other in time in flight and using a charge electrode and a pair of deflection electrodes in such a way that said ink drops may be selectively steered to travel to strike against a recording medium or to a gutter, CHARACTERIZED by providing an ink drop generator with a first ultrasonic transducer and a second ultrasonic transducer so as to impart the ultrasonic vibrations to the pressurized ink,

• energizing normally said first ultrasonic transducer in such a way that the formation of each ink drop or breakup of the ink jet into each ink drop may be so timed that each ink drop may be charged or not charged when only said first ultrasonic transducers is energized or when both said first and second ultrasonic transducers are energized simultaneously in response to the ink-placement signal de-energizing or energizing said second ultrasonic transducer, whereby the formation of each ink drop may be so timed as to cause said each ink drop to be not charged or to be charged thereby steering the uncharged or charged ink drop so as to strike against said recording medium.