Printhead Ball Valve to Prevent Hot Melt Ink Overflow
Publication Date: 2011-Jun-24
The IP.com Prior Art Database
Hot Melt Ink printheads have heated ink reservoirs which supply ink to the inkjet nozzle. Some printheads also have an associated air reservoir in which the air pressure is managed to maintain the appropriate positive or negative air pressure for the liquid ink reservoir. It is important to keep the melted ink out of and away from contaminating the air reservoir, even though the two reservoirs are connected by an air passage. The heated ink reservoir must be refilled periodically as the hot melt ink is depleted. During an ink replenishment procedure, there is an opportunity for unwanted contamination to occur. This idea proposes to add a float ball valve to the print heads to prevent overfilling which can cause ink to flow into the air reservoir or air line that controls pressure in the print head. In the air line the ink cools and solidifies, preventing proper negative pressure during printing or positive pressure during purges. This is not a frequent problem but it does occur and the cleanup is time consuming. By adding a ball float valve to the assembly, unwanted contamination can be avoided.