Patent ID: 8308266

Claim:
A liquid droplet ejecting apparatus comprising: a liquid ejecting module that includes a pressure chamber that has a piezoelectric element and an ejecting nozzle, and a supply passage that supplies liquid into the pressure chamber, the liquid ejecting module configured to eject, from the ejecting nozzles, liquid which is supplied to the pressure chamber through the supply passage; a measurement section that measures a phase difference between a voltage applied to the piezoelectric element and a current through the liquid ejecting module when the voltage is applied, in order to measure fluid viscosity of the liquid in the liquid ejecting module; a resistance calculation section that calculates, based on the phase difference measured by the measurement section, one resistance in a first equivalent circuit that represents electrical characteristics of the liquid ejecting module and that includes a plurality of resistances including a resistance of the supply passage, a resistance of the pressure chamber and a resistance of the ejecting nozzle; and a processing section that performs processing for lowering and adjusting fluid viscosity in the liquid ejecting module based on the one resistance calculated by the resistance calculation section, wherein the processing section performs a process selected from the following processes: preliminarily ejecting the liquid in the liquid ejecting module, pressurizing the liquid in the liquid ejecting module, and pushing the liquid out or applying suction to the liquid, when the liquid droplet electing apparatus is started, the resistance calculation section calculates a resistance of the supply passage, and if the calculated resistance value of the supply passage is greater than a first predetermined value, the calculated resistance of the supply passage is the one resistance, if the calculated resistance value of the supply passage is less than the first predetermined value, a resistance of the pressure chamber is calculated, and if the calculated resistance value of the pressure chamber is greater than a second predetermined value, the calculated resistance of the pressure chamber is the one resistance, if the calculated resistance value of the pressure chamber is less than the second predetermined value, the resistance of the ejecting nozzle is the one resistance; and the processing section performs the process using the amount of the liquid preliminarily ejected or suctioned so as to satisfy the following equation: v 1 <v 2 <v 3, wherein v 1 represents the amount of liquid when the resistance calculated as the one resistance by the resistance calculation section is the resistance of the supply passage, v 2 represents the amount of liquid when the resistance calculated as the one resistance by the resistance calculation section is the resistance of the pressure chamber, and v 3 represents the amount of liquid when the resistance calculated as the one resistance by the resistance calculation section is the resistance of the ejecting nozzle.