| 摘要 |
PURPOSE:To prevent deterioration of printing quality due to foam produced in ink during interruption of power source, by draining ink which has the possibility of containing foam from an ink feed path between an ink tank and an ink nozzle upon throw-in of power source, thereafter starting printing operation. CONSTITUTION:Upon throw-in of power source, an ink pressurizing pump 2 is operated to produce a proper pressure. Then an ink drainage valve 13 is opened followed by opening of an ink feed valve 1. Consequently, such ink as having the possibility of containing foam and the pressure thereof is recovered to normal level during power interruption is drained from an ink feed path between an ink feed valve 7 and an ink drainage valve 13 through an ink drainage tube 14 and recovered into an ink tank 25. The foam recovered into the ink tank together with the ink is separated naturally from the ink before it is pressurized again. Thereafter, the ink feed valve 7 and the ink drainage valve 13 are closed. When a cleaning water feeding device 16 is driven so as to clean the periphery of an orifice 11 of an ink nozzle 10 and the ink feed valve 7 is opened again, ink particles are ejected through the ink nozzle 10, thus enabling printing. |
