| 摘要 |
PURPOSE:To enable an ink jet head to be filled with ink so that no bubble remains inside the ink jet head by a method wherein the ink jet head is filled in no contact with air by liquid which is deformed by a pressure difference from normal pressure. CONSTITUTION:An ink jet head 1, a hose 2, and a bag 4 containing liquid 3 are heated by heaters 6, 7, 8. Valves 11, 12 are opened, and three-way cocks 13, 14 are connected only to a vacuum pump 17 and respective chambers 9, 10. A three-way cock 19 is set to be connected only to the ink jet head 1 and the bag. The pump is operated and respective chambers 9, 10 are degassed to low pressure. Thereafter, the valve 12 is closed, and the three-way clock 14 is so set as to connect an open port 16 to the open air to the chamber 10 containing the bag 4 and air is fed. Thereby, the bag 4 is pressurized. The liquid 3 is pressurized in no contact with air to fill the ink jet head through a hose 2, and comes to be jetted from a nozzle outlet 18. Since surface tension of the liquid is small, the liquid is difficult to remain in bubbles. Even though remained, since the bubble is vapor of the liquid under a low pressure state, it is varied in phase to liquid when the pressure is returned to normal pressure. |
