Multiple-orifice drop-on-demand ink jet print head having improved purging and jetting performance

A method for purging a bubble from an ink jet head having multiple orifices, comprising the steps of:

• providing an ink supply manifold having a volume, a base end, and a tip end, the ink supply manifold being in fluid communication with multiple ink supply channels distributed at locations between the base end and the tip end and having at least a portion of the volume with a linear taper so that a ratio of a cross-sectional area of the tip end to a cross-sectional area of the base end is in a range of about 0.2 to about 0.5;
• providing an ink inlet channel coupling the ink supply manifold to an ink source, the ink supply manifold and ink inlet channel each having a length and a cross-sectional area that causes a combination of the ink inlet channel and the ink supply manifold with the taper to resonate at a frequency above a maximum repetitive operating rate of the orifices;
• and
• causing ink to flow at a flow rate through an ink inlet adjacent to the base end of the ink supply manifold, whereby the portion of the volume with the linear taper maintains everywhere within the ink supply manifold a flow rate-induced drag force on the bubble sufficient to purge the bubble from the ink supply manifold.