Patent ID: 7168795

Claim:
An ink jet recording apparatus, comprising: a recording head which has a plurality of nozzles and which ejects, from each of the nozzles, a droplet of a corresponding one of a plurality of sorts of inks to form an image; an ink-tank supporting portion which supports a plurality of ink tanks which store the inks, respectively, such that the ink tanks are stationary; a plurality of ink-tank-side fluid flow channels which connect the ink tanks to the recording head, respectively, and include a plurality of ink supply tubes, respectively, which supply the inks from the ink tanks to the recording head, respectively, a plurality of buffer tanks which are provided between the ink supply tubes and the recording head and each of which accommodates a corresponding one of the inks, and air bubbles; a discharging device which discharges a fluid from each of the buffer tanks into an outside space; and a plurality of discharging-device-side fluid flow channels which communicate, at respective one ends thereof with the buffer tanks, respectively, while bypassing the recording head, and communicate, at respective other ends thereof, with the discharging device, wherein said plurality of ink-tank-side fluid flow channels comprise first and second ink-tank-side fluid flow channels having respective first liquid flow resistances different from each other, wherein said plurality of discharging-device-side fluid flow channels comprise first and second discharging-device-side fluid flow channels having respective second liquid flow resistances different from each other, wherein the first discharging-device-side fluid flow channel that communicates with the first ink-tank-side fluid flow channel has the second liquid flow resistance smaller than the second liquid flow resistance of the second discharging-device-side fluid flow channel that communicates with the second ink-tank-side fluid flow channel that has the first liquid flow resistance greater than the first liquid flow resistance of the first ink-tank-side fluid flow channel.