| 摘要 |
PURPOSE:To obtain the titled device, by which nozzle clogging is detected based on presence or absence of temperature decrease in a body to which ink is jetted due to heat of vaporization of the jetted ink, and the normal state of the nozzle is judged before the printer operation. CONSTITUTION:When a head 1 is located at home position, a nozzle test controlling part 9 energizes a drive control circuit 11 and applies testing dot pulses to a piezoelectric element 4, which drives a specified nozzle. Ink particles jetted from the nozzle are made to hit the surface of a temperature sensor 3 and attached on it. Then the temperature of the sensor is decreased. When the rapid temperature change is detected based on the signal from the temperature sensor 3, a clog detecting circuit 12 outputs a normal signal to a control part 9 through an AND gate 13. When the nozzle is clogged and the ink particles are not jetted, the temperature change is not yielded in the temperature sensor 3. Therefore, the normal signal is not outputted from the circuit 12. |
