Inkjet recording apparatus

An inkjet recording apparatus comprising:

• a plurality of nozzles each of which can eject ink droplets toward a recording medium, and configured to have a meniscus of ink formed therein;
• pressurizing chambers that communicate with the plurality of nozzles, respectively, and into which ink is charged;
• a piezoelectric element that is deformed by a driving voltage being applied, and operates to eject the ink having been charged into the pressurizing chambers, as ink droplets, from the nozzles;
• an ambient condition obtaining portion that can obtain an ambient condition;
• an application portion that applies the driving voltage to the piezoelectric element;
• and
• a control portion that causes the application portion to output an ejection driving voltage by which the piezoelectric element is deformed so as to eject droplets from the nozzles in a printing period in a printing state, and that causes the application portion to output a vibration driving voltage by which the piezoelectric element is vibrated a predetermined number of times so as to vibrate a meniscus in each nozzle in a non-printing period between printing periods in the printing state, wherein
• the control portion changes the number of times the piezoelectric element is vibrated in the non-printing period, based on the ambient condition obtained by the ambient condition obtaining portion, and causes the application portion to output a vibration driving voltage by which the piezoelectric element is vibrated the number of times, per unit time, which has been changed,
• the ambient condition obtaining portion can obtain a humidity condition,
• the control portion executes:
• a first mode in which the control portion chances the number of times the piezoelectric element is vibrated in the non-printing period, based on the ambient condition obtained by the ambient condition obtaining portion, and the control portion does not cause the application portion to output the vibration driving voltage by which the piezoelectric element is vibrated the changed number of times, and
• a second mode in which the control portion changes the number of times the piezoelectric element is vibrated in the non-printing period, based on the ambient condition obtained by the ambient condition obtaining portion, and the control portion causes the application portion to output the vibration driving voltage by which the piezoelectric element is vibrated the changed number of times, and
• the control portion can switch between the first mode and the second mode, based on the humidity condition obtained by the ambient condition obtaining portion.

An inkjet recording apparatus comprising:

• a plurality of nozzles each of which can eject ink droplets toward a recording medium, and configured to have a meniscus of ink formed therein;
• pressurizing chambers that communicate with the plurality of nozzles, respectively, and into which ink is charged;
• a piezoelectric element that is deformed by a driving voltage being applied, and operates to eject the ink having been charged into the pressurizing chambers, as ink droplets, from the nozzles;
• an ambient condition obtaining portion that can obtain an ambient condition;
• an application portion that applies the driving voltage to the piezoelectric element;
• a zero shear viscosity calculating/obtaining portion that calculates or obtains a zero shear viscosity of ink, based on the ambient condition obtained by the ambient condition obtaining portion, and
• a control portion that causes the application portion to output an ejection driving voltage by which the piezoelectric element is deformed so as to eject droplets from the nozzles in a printing period in a printing state, and that causes the application portion to output a vibration driving voltage by which the piezoelectric element is vibrated a predetermined number of times so as to vibrate the meniscus in each nozzle in a non-printing period between printing periods in the printing state, wherein
• the control portion changes the number of times the piezoelectric element is vibrated in the non-printing period, based on the zero shear viscosity calculated or obtained by the zero shear viscosity calculating/obtaining portion, and causes the application portion to output the vibration driving voltage by which the piezoelectric element is vibrated the number of times having been changed.