Patent ID: 8827700

Claim:
A droplet spray generating apparatus for use in an oral cleaning device, comprising: a sprayhead housing ( 60 ) having an orifice plate ( 62 ) therein with at least one orifice opening ( 64 ) therethrough; a source of liquid; a liquid line system ( 36 ) for delivering liquid from the source of liquid to the sprayhead housing, above the orifice plate, wherein the liquid flow rate through the orifice opening is sufficiently great relative to the size of the orifice opening that the liquid moves through the orifice opening and exits therefrom as a stream of liquid; a source of gas; and a gas line system ( 38 ) for delivering gas from the source of gas to the sprayhead housing, through at least two openings in the sprayhead housing, wherein the two openings are downstream of the orifice opening, said two openings being oriented such that the gas flow therefrom impacts the liquid stream from the orifice opening approximately 180° apart and wherein the gas flow strikes the liquid stream approximately perpendicularly, wherein the sprayhead housing includes a droplet acceleration portion ( 66 ) downstream from the sprayhead housing portion and downstream from the two openings in the sprayhead housing, with the acceleration portion comprising an outlet duct having a diameter in the range of 0.4 to 0.6 mm, which is approximately equal to or smaller than the portion of the sprayhead housing having the gas openings; the orifice opening having a diameter in the range of 150-350 μm, wherein the interior of the sprayhead is structured and arranged relative to the gas flow through the gas opening such that the gas flow strikes the liquid stream from the orifice opening with a velocity and flow rate sufficient to break up the liquid stream into a spray of droplets having sufficient size and sufficient velocity, in the range of 25-70 meters per second, to produce cleaning of the teeth.