Patent ID: 7878621

Claim:
An ink jet printer, comprising: a housing; a plurality of recording heads each of which has at least one nozzle opening in a lower surface thereof and ejects, from said at least one nozzle, droplets of ink so as to record an image on a recording medium; a carriage which is movable in the housing and which carries the plurality of recording heads; a plurality of ink tanks which store at least one sort of ink to be supplied to the plurality of recording heads; a plurality of ink flow passages which supply said at least one sort of ink from the plurality of ink tanks to the plurality of recording heads, respectively; a plurality of air collecting chambers which are provided on the carriage and each of which collects air bubbles produced in a corresponding one of the plurality of ink flow passages; a plurality of discharging passages which are provided on the carriage and each of which communicates with a corresponding one of the plurality of air collecting chambers; a plurality of first opening and closing valves each of which is normally closed and is provided in a corresponding one of the plurality of discharging passages such that the plurality of first opening and closing valves are arranged in a first direction; a plurality of opening and closing bars which are supported by the housing such that the plurality of opening and closing bars are arranged in a second direction parallel to the first direction, and each of which opens and closes a corresponding one of the plurality of first opening and closing valves; an air-tight-space defining device including an air-discharge cap which has a bottom wall, a side wall projecting upward from a periphery of the bottom wall, and a suction hole, wherein the air-tight-space defining device is supported by the housing such that said each of the opening and closing bars air-tightly extends through a thickness of the bottom wall of the air-discharge cap and is movable relative to the air-discharge cap, and such that an upper end surface of the side wall of the air-discharge cap is closely contactable with a lower surface of the carriage to cover respective openings of the plurality of discharging passages and define an air-tight space communicating with each of the respective openings; a suction device which sucks air through the suction hole of the air-discharge cap; and an air-flow generating device which causes an air flow inlet of the air-discharge cap to open at a position distant from the suction hole in a third direction having a first component parallel to the bottom wall of the air-discharge cap, so that when the suction device sucks the air through the suction hole, the air flows from the air flow inlet toward the suction hole in a fourth direction having a second component opposite to the first component of the third direction.