Inkjet recording device and method for controlling inkjet recording device

An inkjet recording device comprising:

• a nozzle that atomizes an ink to eject ink particles;
• a charging electrode that charges the ink particles, which have been ejected from the nozzle, to correspond to a printing character;
• a deflection electrode that deflects the charged ink particles which have passed through the charging electrode;
• a gutter that captures a non-charged ink;
• an ink supply path that supplies the ink in a main ink container to the nozzle;
• an ink recovery path that recovers the non-charged ink, which has been captured by the gutter, to the main ink container;
• a solvent replenishment unit that supplies a solvent to the main ink container;
• a control unit that controls an entirety of the device;
• a heating device that is installed between the ink supply path and the nozzle to heat the ink;
• a thermometer that detects an ink temperature of the ink heated by the heating device;
• and
• a viscometer that detects a viscosity of the ink in the main ink container are provided,
• wherein the control unit controls the heating device based on the temperature detected by the thermometer such that the temperature reaches a set temperature set in a range of an ink viscosity which enables printing, and controls an amount of supply of the solvent based on a detection value of the viscometer to regulate the viscosity of the ink in the main ink container to a predetermined ink viscosity, and
• wherein the control unit determines whether or not the ink to be used has a high viscosity specification, based on a determination criterion determined in advance as to whether or not the viscosity is high, applies an excitation voltage, which corresponds to a maximum usage temperature of the ink, to the nozzle when the viscosity is determined to be high, and applies a second excitation voltage, which corresponds to the ink temperature, to the nozzle when the viscosity is determined not to be high.