Patent ID: 7914103

Claim:
A liquid droplet jetting apparatus which jets liquid droplets of a liquid, comprising: a liquid droplet jetting head having a cavity unit in which a pressure chamber extending in a predetermined direction and having a predetermined volume and a nozzle communicating with the pressure chamber are formed, and a piezoelectric actuator which is joined to the cavity unit to cover the pressure chamber, and which applies pressure to the liquid in the pressure chamber; and a controller which controls the piezoelectric actuator in a liquid droplet jetting mode of jetting the liquid droplets from the nozzle and in a warm-up mode of heating the liquid in the pressure chamber without jetting the liquid in the pressure chamber as the liquid droplets from the nozzle, wherein in the liquid droplet jetting mode, the controller controls the piezoelectric actuator to perform a liquid droplet jetting operation by which volume of the pressure chamber is decreased to a decreased volume smaller than the predetermined volume, and then the volume of the pressure chamber is increased to a increased volume greater than the predetermined volume, and the volume of the pressure chamber is again decreased to the decreased volume; and in the warm-up mode, the controller controls the piezoelectric actuator to perform at least one of a first warm-up operation to change the volume of the pressure chamber repeatedly between the predetermined volume and the increased volume, and a second warm-up operation to change the volume of the pressure chamber repeatedly between the predetermined volume and the decreased volume.