Patent ID: 7699420

Claim:
A voltage control device for a liquid injection head comprising: a waveform generator for setting a drive waveform to be applied to the liquid injection head that injects a liquid from a nozzle by changing a drive voltage, wherein the waveform generator includes a first drive waveform generator that outputs a first drive waveform for liquid injection, and a second drive waveform generator that outputs a second drive waveform for voltage correction; a selector that selects a drive waveform from the waveform generator to either one of the first drive waveform and the second drive waveform; a voltage determining device that determines a voltage of the drive waveform set by the waveform generator; a voltage amplifier that boosts a voltage to be applied to the liquid injection head so as to be the voltage determined by the voltage determining device; a waveform amplifier that amplifies the drive waveform set by the waveform generator so that the voltage of the drive waveform is the voltage boosted by the voltage amplifier; a voltage reader that reads a voltage of the second drive waveform amplified by the waveform amplifier, and a voltage adjuster that compares the voltage of the second drive waveform read by the voltage reader with voltage determined by the voltage determining device, calculates a correction value from a result of the comparison, adds a correction to the voltage determined by the voltage determining device based on the correction value.