Patent ID: 9662877
Date: 2017-05-30
CPC Classifications: B41J

Claim:
1. A pressure-type inkjet head that makes an actuator apply pressure to ink in a pressure chamber and thereby ejects the ink from the pressure chamber, the inkjet head comprising: a plurality of ink feeding holes through which ink is supplied into the pressure chamber; and a driver circuit that generates a driving signal for driving the actuator, wherein the plurality of ink feeding holes have different flow-path resistances, when ink is not being ejected from the pressure chamber, the driver circuit generates, as the driving signal, a driving signal for circulating ink which differs from a driving signal for ejecting ink, and applies the driving signal for circulating ink to the actuator, and by being driven based on the driving signal for circulating ink, the actuator makes ink in the pressure chamber circulate by making a flow amount of ink flowing through each of the plurality of ink feeding holes differ between when ink is drawn into the pressure chamber and when ink is discharged from the pressure chamber, wherein, in an application period in which at least one pulse is included, the application period being a repetition unit in making ink in the pressure chamber circulate, a waveform of the driving signal for circulating ink is asymmetrical between a side of a start of the application period and a side of an end of the application period, the start of the application period corresponding to a start of decompression of an inside of the pressure chamber, the end of the application period corresponding to an end of pressurization of the inside of the pressure chamber, and wherein, in a case where a plurality of pulses are included in the application period, the driving signal for circulating ink has a waveform in which the plurality of pulses included in the application period are different from each other in pulse width or pulse potential.