Ink jet deaeration apparatus

摘要

An apparatus for removing air from ink which is fed under pressure to a nozzle of an ink ejection head is disclosed. A first solenoid-operated valve is disposed between an ink pressurizing source and the nozzle. Located between the valve and the nozzle is a deaerating unit which has therein a bore for causing air entrained by the ink to surface. An air outlet is formed in an upper portion of the bore and opened and closed by a second solenoid-operated valve. Upon a stop of ink ejection, the first valve is closed (ink supply blocked) while the second valve is opened. Heaters are installed in the bore of the deaerating unit to heat ink inside the bore to a predetermined temperature, so that air in the ink is expanded to become readily separable from the ink.