Abstract: A liquid spray is characterized by a liquid jet which is cyclically deflected at a high frequency such that it breaks up into a fan-shaped spray pattern in which the fluid distribution and droplet size can be controlled. Jet deflection is accomplished with energy in the pressurized liquid itself. In a preferred embodiment, the spray is produced by a fluidic oscillator, of the type having a flow-reversing interaction region terminated by an outlet throat from which outlet walls diverge, configured to establish a static operating pressure at the upstream end of the interaction region which is positive relative to the pressure in the outlet region.

Abstract: An improved oral irrigation technique is characterized by an oscillatory swept water jet issued to sweep back and forth at high frequencies across the user's gums and teeth. High frequency operation is achieved by oscillating the jet itself rather than the jet-issuing body. The high frequency sweeping jet effects faster cleaning action and more effective gum massage than prior art pulsed jet irrigators having lower effective operating frequencies.