Patent ID: 8308259

Claim:
A driving device for a liquid droplet jetting device, the liquid droplet jetting device including a plurality of pressure chambers which includes first and second pressure chambers disposed along a predetermined direction with respect to a nozzle from which a liquid droplet is jetted, a first pressure generating unit provided corresponding to the first pressure chamber, and a second pressure generating unit provided corresponding to the second pressure chamber, the first pressure generating unit generating pressure for jetting a liquid droplet outside the nozzle after pulling the liquid inside the nozzle when a first voltage of a predetermined first waveform for jetting the liquid droplet outside the nozzle after pulling the liquid inside the nozzle is applied, the second pressure generating unit generating pressure for deforming a liquid level of the liquid pulled inside the nozzle by applying the first voltage when a second voltage of a second waveform, whose voltage value is smaller than that of the first waveform, for deforming the liquid level of the liquid pulled inside the nozzle by applying the first voltage to the first pressure generating unit is applied, the driving device comprising: an application unit that generates the first voltage of the first waveform and applies the first voltage of the first waveform to the first pressure generating unit and that generates the second voltage of the second waveform and applies the second voltage of the second waveform to the second pressure generating unit; and a controller that controls the application unit to generate a waveform which includes at least one of a third waveform or a fourth waveform as the second waveform and to apply the waveform to the second pressure generating unit, the third waveform being set in advance according to a jetting angle from a reference jetting direction in order to change a liquid droplet jetting direction from the reference jetting direction to the predetermined direction by deforming the liquid level of liquid pulled inside the nozzle in a direction of pushing the liquid level outside the nozzle, and the fourth waveform being set in advance according to a jetting angle from the reference jetting direction in order to change the liquid droplet jetting direction from the reference jetting direction to the predetermined direction by deforming the liquid level of liquid pulled inside the nozzle in a direction of further pulling the liquid level inside the nozzle, wherein assuming that a start time of the first waveform corresponding to a start of an operation of pulling liquid inside the nozzle is T 0 , a natural period of a pressure elastic wave of the first pressure chamber is Tx, and a phase difference between the first and second waveforms is tc, the controller controls the application unit such that expression (1) is satisfied, T 0 −Tx/ 4 ≦tc<T 0 +Tx/ 2 (1).