Ink Dump for Ink Jet Printers
Original Publication Date: 1981-Apr-01
Included in the Prior Art Database: 2005-Feb-11
In the IBM 6640 ink jet system, the ink stream supplied to the head is turned on and off with a two-way valve. In the first position with the ink stream on, the inlet port of the valve is connected directly to the head; in the second position when the valve is off, the inlet is stopped up and a port is opened from the head to the vent line which allows the pressure to drop very quickly to atmospheric pressure in the head, preventing contamination of the nozzle face. Any excess ink which is vented is pushed through a dump line to the siphon break which is connected to a surge tank. The dump tank described hereinafter inhibits excessive air flow through the nozzle orifice, which results in evaporation and ultimate clogging of the valve's internal passageway (and nozzle).