| 摘要 |
PURPOSE:To deaerate assuredly and secure a constant air layer in an ink liquid chamber, by a method wherein an opening part on the air layer side of a vent port communicated with an air layer provided in an ink liquid chamber is opened and closed by a solenoid valve. CONSTITUTION:The vent port 11 of a small diameter pipe communicated with the air layer 7 in the ink liquid chamber is provided in proximity to a nozzle orifice 10. The solenoid valve 9 is provided on the port 11. When the liquid surface of the ink 6 is lowered as recording proceeds, the ink is fed under pressure through a connecting pipe 14, and an electric current is passed to the valve 9, whereby an iron core 17 is moved upward against an energizing force of a spring 15 to open the opening part 11a, resulting in that air increased in amount is discharged to the exterior through the vent port 11. When the ink starts to leak through the port 11, the passage of the electric current to the valve 9 is stopped, and after causing the ink to leak also through the nozzle orifice 10, pressure feeding of the ink is stopped. When the diameter of the vent port 11 is set to be larger than that of the orifice, the liquid surface of the ink 6 can be easily raised, and can be set to a fixed level in a short time. |
