| 摘要 |
PURPOSE:To prevent ink head nozzles from getting clogged by a method wherein a small amount of gas is fed from a gas bomb to an ink head during stoppage of ink jet so as to cause ink to drip from the ink head nozzles at all times. CONSTITUTION:When ink jet is stopped after the completion of printing operation, an electromagnetic three way value 13 is operated simultaneously to switch an ink passage so that a gas bomb 14 containing inert gas such as N2 pressurized therein is communicated with an ink chamber 3 of an ink head 1. When the inert gas is fed into the ink chamber 3, the ink within the ink chamber 3 is pushed out with a pressure of the fed gas and then dropped down from a tip end of a nozzle 2 in the form of a fine drip. The dropped ink is received by an ink receiver 6 disposed just below the nozzle end and then returned to an ink tank 8 via a filter 7. An amount of ink dripping from the nozzle 2 is very small, so that the ink of 1- several 10's cc is enough for stoppage of operation ranging over a few months. By so doing, printing operation can be immediately started even after long term stoppage of operation. |
