Patent ID: 7401876

Claim:
An ink jet printer comprising: an ink chamber; a nozzle connected with the ink chamber; a pressure chamber located between the ink chamber and the nozzle; a piezoelectric element facing the pressure chamber; a temperature sensor for measuring at least one of a temperature of ink and a surrounding temperature of the ink jet printer; and a controller programmed to perform a first change of voltage applied to the piezoelectric element and a second change of voltage applied to the piezoelectric element and to change a period between the first change and the second change based on the temperature measured by the temperature sensor, wherein the controller adopts a short period when the temperature is high, and the controller adopts a long period when the temperature is low the controller adopts a first period when the temperature is higher than a first predetermined temperature, the controller adopts a third period when the temperature is lower than a second predetermined temperature, the first period is shorter than the third period, and the first predetermined temperature is higher than the second predetermined temperature.