Patent ID: 8493222

Claim:
A liquid injection device injecting liquid from an injection nozzle, comprising: a liquid chamber which receives supply of the liquid and connects with the injection nozzle; a liquid chamber volume varying unit to which driving voltage is applied to reduce the volume of the liquid chamber to a volume smaller than the volume of the liquid chamber before the driving voltage is applied; a driving voltage applying unit which applies the driving voltage to the liquid chamber volume varying unit with the liquid supplied to the liquid chamber; a pseudo driving noise data memory unit which stores sound data of pseudo driving noise having at least a part of audible frequency components contained in driving noise generated when the driving voltage is applied to the liquid chamber volume varying unit; and a pseudo driving noise outputting unit which outputs the pseudo driving noise by using the sound data of the pseudo driving noise such that the sound pressure of the driving noise decreases within the audible frequency range when the driving voltage is applied.