| 摘要 |
PROBLEM TO BE SOLVED: To reduce the running cost by detecting an acoustic signal produced from a bubble, controlling the recording operation based on the decision results of ejecting state of ink and discharging only thickened ink in a nozzle at the time of preliminary ejecting or replacing ink thereby reducing the quantity of ink to be discharged. SOLUTION: A piezoelectric electroacoustic converter 40 is fixed closely to a heating element in order to detect a sound wave produced from a bubble heated by the heating element and the detected sound wave is fed through an amplifier 41 to a comparator 42. A ejecting state decision unit 45 decides the ejecting state based on the output from comparartor 42 and delivers a preliminary ejecting sustention signal to a recording operation controller 43 when the ink ejecting state is normal otherwise delivers a stop signal. Since only a thickened ink in each liquid channel can be ejected surely regardless of the environmental fluctuation or the difference in the extent of evaporation of volatile component in the ink, quantity of ink can be reduced at the time of preliminary ejecting. |
