Patent ID: 6494556
Filing Date: 2002-12-17
Classification: B41J

Abstract:
A liquid jetting apparatus comprising:a nozzle orifice from which a liquid drop is ejected; a pressure chamber communicated with the nozzle orifice; a pressure generating element for generating pressure change in liquid in the pressure chamber; a drive signal generator for generating a drive signal including: a vibration pulse signal configured to vibrate a meniscus of the liquid in the nozzle orifice, which is separated into at least one pressure reducing element configured to reduce pressure of the liquid in the pressure chamber to such an extent that a liquid drop is not ejected from the nozzle orifice and at least one pressure increasing element configured to increase pressure of the liquid in the pressure chamber to such an extent that a liquid drop is not ejected from the nozzle orifice; and a plurality of ejection pulse signals each including an ejection element configured to eject liquid drop from the nozzle orifice, at least one of the ejection elements being placed between the pressure reducing element and the pressure increasing element; and a pulse supplier for selectively supplying at least one of the pressure reducing element, the pressure increasing element and the ejection element from the drive signal to the pressure generating element so as to generate pressure change in liquid in the pressure chamber in accordance with the configuration of the respective elements, wherein the pressure reducing element and the pressure increasing element are never selected with the ejection pulse signal when the ink drop is ejected.