LIQUID DISCHARGE DEVICE, HEAD UNIT CONTROL CIRCUIT FOR CONTROLLING HEAD UNIT OF LIQUID DISCHARGE DEVICE, AND METHOD FOR DETERMINING DISCHARGE STATE OF LIQUID IN DISCHARGING PORTION OF LIQUID DISCHARGE DEVICE

摘要

PROBLEM TO BE SOLVED: To determine a discharge state of liquid in a discharging portion without setting a determination criterion for each discharging portion.;SOLUTION: The liquid discharge device comprises: a discharging portion which is provided with a piezoelectric element which is supplied with a driving signal and is displaced according to change in potentials of the driving signal, a pressure chamber whose volume is varied according to the displacement of the piezoelectric element and a nozzle that can discharge liquid filled into the pressure chamber according to the variation of the volume of the pressure chamber; a supplying portion that can supply to the piezoelectric element a first driving waveform signal or a second driving waveform signal having a waveform different from the first driving waveform signal as the driving signal; a detecting portion that outputs a first residual vibration signal representing a residual vibration which occurs at the discharging portion when the supplying portion supplies the first driving waveform signal as the driving signal to the piezoelectric element and outputs a second residual vibration signal representing a residual vibration which occurs at the discharging portion when the supplying portion supplies the second driving waveform signal as the driving signal to the piezoelectric element; and a determining portion that determines a discharge state of liquid in the discharging portion on the basis of the first residual vibration signal and the second residual vibration signal.;SELECTED DRAWING: Figure 14;COPYRIGHT: (C)2017,JPO&INPIT