Patent ID: 7553004

Claim:
An ink-jet recording apparatus comprising: an ink container that comprises an ink bag containing ink and a case holding said ink bag air-tightly; a recording head placed below said ink container and supplied with the ink from said ink bag through an ink supply path, said recording head discharging the ink through a nozzle by an amount variable in accordance with image data to print an image; a case internal pressure adjusting device for adjusting pressure in a space between said ink bag and said case by sucking or sending air from or into said case; a pumping height predictor that predicts a consumption of the ink in a given time based on image data to be used for printing later in the given time, and predicts based on the predicted consumption of the ink a pumping height of the ink from an outlet of said nozzle to a liquid surface of the ink in said ink bag at the given time after, while said recording head is printing the image; and a control device for controlling said case internal pressure adjusting device so as to keep pressure in said nozzle in a predetermined range, depending upon the predicted pumping height.