Patent ID: 11141989

Abstract:
An electrohydrodynamic (EHD) jet printing apparatus or system may include circulation of printing fluid to minimize or eliminate clogging in a nozzle. An exemplary nozzle comprises at least two ink channels—one allowing flow to a droplet emitting opening and one allowing flow away from the droplet emitting opening—configured for circulating ink. The nozzle may transfer ink to a substrate with an EHD technique involving voltage or current modulation. For example, an electric field may be applied between the nozzle and printing substrate such that the ink meniscus changes shape and releases ink from the tip of the liquid cone. A multi-channel nozzle may take a variety of configurations, including two co-axially aligned capillaries, side-by-side parallel capillaries, or capillaries arranged at an angle with respect to one another but converging at a single point where the conical meniscus is formed.