| 摘要 |
PROBLEM TO BE SOLVED: To provide an image-forming apparatus which can suppress an unnecessary consumption of ink by reducing the quantity of ink to be sucked in accordance with the recovery of an ink discharge state. SOLUTION: A rotor 34 of a switching valve 30 is rotated from a shut position to open a first valve path 34a and a first ink channel R1, to make the negative pressure generated by a suction pump 26 act on nozzle openings 21a. After the first ink channel R1 is opened, the negative pressure application time is controlled in accordance with contents of a purge process, e.g. a size of a time passed after ink is exchanged or after a previous purge process, and the rotor 34 of the switching valve 30 is moved to the shut position to shut the first ink channel R1. Since the switching valve 30 shuts the ink channel R1 after opening the channel for a predetermined time, the ink is suppressed not to flow into the whole region of the ink channel R1. Accordingly, the ink of a required or more quantity is prevented from being sucked from each nozzle opening 21a of a printing head 21, and the unconsidered consumption of the ink is suppressed. COPYRIGHT: (C)2008,JPO&INPIT |
