Abstract: An ink-jet printer and an apparatus and a method of driving a recording head for an ink-jet printer for suppressing satellite droplets. Two piezoelectric elements are provided for every ink chamber corresponding to each nozzle. Timing of displacement of the piezoelectric elements is adjusted by applying a drive signal for ink droplet ejection to one of the piezoelectric elements and a drive signal for suppressing satellite droplets when a droplet is ejected to the other piezoelectric element. An auxiliary pressure generated by the displacement of the latter piezoelectric element is superimposed on an ejection pressure generated by the displacement of the former piezoelectric element. Trailing of an ink droplet is cut off at an early stage and generation of satellite droplets is suppressed.

Abstract: An ink-jet printer and an apparatus and a method of driving a recording head for an ink-jet printer are provided for faithfully performing various image representations through ink droplet ejection driving signals of different waveforms. Based on a waveform selection signal from a selection controller, a waveform selector selects one of a plurality of drive signals from a drive waveform generator in a time-division manner. The selected signal is supplied to a piezoelectric element of a corresponding nozzle. Control is thereby performed on ink droplet ejection with a drive signal having a temporally varying waveform. The drive signals include a signal having a varying voltage waveform that disables ink droplet ejection in isolation from another waveform. A new composite drive signal waveform is generated by time-divisional selection not only at a point between ejection cycles but also at a point during the ejection cycle.

Abstract: An ink-jet printer and a drive method for driving a recording head of an ink-jet printer are provided for controlling a size and a velocity of an ejected ink droplet. The ink-jet printer includes a droplet outlet orifice through which an ink droplet is ejected, an ink chamber communicating with the outlet orifice, an ink feed duct for feeding ink to the ink chamber, and a piezoelectric element for expanding and contracting the ink chamber in response to an applied voltage. A process for ink ejection includes a first step in which a meniscus in the outlet orifice is retracted towards the ink chamber by expanding the ink chamber, a second step in which the meniscus is moved towards the orifice by filling the chamber with ink, and a third step in which an ink droplet is ejected by contracting the ink chamber. The size and the velocity of the ink droplet ejected in the third step are controlled by controlling a position and a velocity of periodic travel of the meniscus at a start point of the third step.