Patent ID: 6478395
Filing Date: 2002-11-12
Classification: B41J

Abstract:
A liquid jetting apparatus comprisinga pressure chamber having an inside space whose volume is changeable, into which a liquid is supplied and which is communicated with a nozzle, a Helmholtz resonance frequency of said pressure chamber having a period of TH, a signal-generating unit that can generate a driving signal including: a first signal-element for causing the pressure chamber to expand, a second signal-element for causing the pressure chamber to contract from an expanded state thereof in order to jet a drop of the liquid through the nozzle, and a third signal-element for causing the pressure chamber to expand to an original state before outputting the first signal-element after the drop of the liquid is jetted, and a pressure-generating unit that can cause the pressure chamber to expand and contract, based on the driving signal, wherein an interval between a starting time of outputting the first signal-element and a starting time of outputting the second signal-element is set substantially equal to the period TH of the Helmholtz resonance frequency, an interval between a starting time of outputting the second signal-element and a starting time of outputting the third signal-element is also set substantially equal to the period TH of the Helmholtz resonance frequency, and a sum of an amplitude of the first signal-element and an amplitude of the third signal-element is set substantially equal to an amplitude of the second signal-element.