An improved Electrohydrodynamic (EHD)
nozzle particularly suitable for a handheld pulmonary
aerosol inhaler increases the consistent and efficient dispensing of therapeutic liquids by reducing or eliminating
wetting through shielding of
discharge electrodes. Some versions further eliminate
wetting while enhances
neutralization of the
aerosol through presentation of a
corona wind of ions annularly surround the
aerosol. Incorporation of improved liquid distribution with consistent pressure drops to each EHD
nozzle tip allows horizontal dispensing, and by using
dielectric nozzle tips with low
surface energy to thereby avoid wicking between dispenses and to advantageously reduce achievable particle size when dispensing. Some versions feature enhanced snap-fit
assembly and other manufacturability advantages. One of the unique features of the EHD nozzles is achieved high
dose rate (microliters / minute) with low
wetting and
small particle size (1.0-5 microns), although these properties tend to be mutually exclusive. Furthermore, these attributes are incorporated into a conveniently small, handheld device.