device for the displacement of vermin by using ultrasonic waves

摘要

A resonator and resonator combination for continuously producing ultrasonic vibrations of frequencies effective to drive away pests, e.g., rodents. The resonator has a housing provided with an internal cavity and an outwardly flaring horn in communication with and spaced from said fluid jet producing means. A rigid airfoil, which may be integral with said housing, projects into the path of flow of fluid from the jet producing means to the jet obstruction means. The resonator can be used in combination with a means to continuously supply air under pressure to the jet producing means and characterized by cycle pulsation to cyclically vary the amplitude of the ultrasonic vibrations, said means preferably comprising an expansible chamber axially aligned with and closely connected with said jet producing means.