THERMAL INK JET PRINTHEAD WITH LOCATION CONTROL OF BUBBLE COLLAPSE

摘要

A thermal ink jet printhead is disclosed having an ink channelgeometry that controls the location of the bubble collapse on the heatingelements. The ink channels provide the flow path between the printheadink reservoir and the printhead nozzles. In one embodiment, the heatingelements are located in a pit a predetermined distance upstream from thenozzle. The channel portion upstream from the heating element has alength and a cross-sectional flow area that is adjusted relative to thechannel portion downstream from the heating element, so that theupstream and downstream portions of channel have substantially equal inkflow impedances. This results in controlling the location of the bubblecollapse on the heating element to a location substantially in the center ofthe heating elements.