Patent ID: 8328309
Filing Date: 2012-12-11
Classification: B41J

Abstract:
1. An ink jet head comprising: a pressure chamber filled with liquid; a nozzle discharging the liquid that is in the pressure chamber; an actuator changing the capacity of the pressure chamber; and a processor which repeatedly outputs a waveform voltage including, in order, an expansion pulse for expanding the capacity of the pressure chamber, a ground potential for returning the capacity of the pressure chamber back to a normal state from the expansion caused by the expansion pulse, a contraction pulse for contracting the capacity of the pressure chamber, and a ground potential for returning the capacity of the pressure chamber back to the normal state from contraction caused by the contraction pulse, as a driving voltage with respect to the actuator, sets the time period of the expansion pulse to be half of the natural vibration period of the liquid, sets the time period from the midpoint of the expansion pulse to the midpoint of the contraction pulse to be the natural vibration period, and sets the time period from the midpoint of the contraction pulse to the midpoint of the expansion pulse to be the natural vibration period.