| 摘要 |
PURPOSE:To make it possible to obtain an image with good quality, in an ink jet printer, by removing a fluid present in a part into which air bubbles are mixed from the opening provided to the terminal end part of the fluid flowline of an ink nozzle head in accordance with the air bubble detection result. CONSTITUTION:In order to detect air bubbles mixed into a pipe 23 between a multi-nozzle head 21 equipped with ink nozzle rows 22 and an ink tank 24, electrodes 28, 29 are respectively arranged to the head 21 and the tank 24. When air bubbles 26 are mixed into the pipe 23 and the supply of an ink is stopped, resistance between the electrodes 28, 29 is increased to a large extent to reduce a current value while the detected output voltage of potential difference from an output terminal 33 through a differential amplifier 32 is extremely lowered. By this detected output, sucking operation is carried out for a predetermined time by a pump 72 to remove mixed air bubbles. When air bubbles can not be removed even if this operation is carried out, an alarm is issued to inform the necessity for performing proper operation for removing mixed air bubbles. |
