| 摘要 |
PURPOSE:To make it possible to arrange many nozzles in a printing head by such an arrangement wherein a thin layer ink feeding unit having capillary action is commonly arranged for plural jet channel systems and the valves of an ink supply outlet are opened or closed by signals from a liquid level detection circuit. CONSTITUTION:When ink is continuously spouted under the closed condition of an automatic open and close valve 22, the level of an ink storage 14 falls by the amount of spouting and if it falls below an electrode 20-1, electrical continuity between electrodes is cut off and the automatic open and close valve 22 is opened by a signal from a liquid level detection circuit 21. Ink in the ink storage ascends by the capillary action of the thin layer ink supply unit 13 and it is supplied to a pressure chamber 12 of each jet channel system by such an amount corresponding to that of ink spouted. Since ink equilibrium condition at a nozzle hole 11 is determined by only surface tension, there is no necessity for maintaining the balance with the static pressure of the ink storage. Consequently, it is possible to increase the number of nozzles, since a head does not require a mechanism for accurately controlling the static pressure of ink. |
