摘要 |
<p>A two-stage liquid spray device having an outlet region with an island (41) and an exit aperture (47) and a fluidic oscillator (33) driving said outlet region. The improvement for the spray device is operable at a low pressure to achieve full-area coverage with substantially uniform droplets and wherein all of the spray droplets land on the desired work surface and do not bounce. The fluidic oscillator includes an oscillation chamber (33), a power nozzle (31) for introducing a jet of liquid from a source into the oscillation chamber. The oscillation chamber is configured to produce a pair of alternating control vortices which substantially preclude wall attachment of said jet traversing said oscillation chamber, thus avoiding a heavy endedness in the oscillatory jet. An outlet from the oscillation chamber to the outlet region, whereby the jet rhythmically sweeps in end pulses to each side of the island and forms a sheet at the exit aperture. The sheet is rhythmically waved or swept in the ambient air to form the uniform droplets. A transverse slot defines the lateral boundary of the sweeping sheet.</p> |