| 摘要 |
PROBLEM TO BE SOLVED: To estimate the number of printable sheets among a user desired number of sheets by detecting a quantity of remaining ink, calculating a quantity of ink to be consumed from the number of discharge times of ink to be discharged from a recording head within a predetermined period and the number of suction times, and calculating and informing the number of printable sheets. SOLUTION: A photointerrupter 11 irradiates light to a lower face of an ink tank 3. In a state without the ink as compared with a state in which the ink is full, a reflectance of light irradiated from the photointerrupter 11 is larger. Thus the presence/absence of the ink can be detected from a difference of the reflectances. A consumption quantity of the ink during printing is calculated by counting the number of print dots or print sheets, the number of automatic preparatory discharges, automatic suctions conducted for preventing a discharge failure during printing or the like reason. How many sheets of a page printed at the time can be printed more is calculated from a quantity of remaining ink and the consumption quantity of ink. The calculated number of printable sheets is displayed to a panel of a printer. |
