Sound emitter

Sound emitter comprising a metal chassis that supports a circuit generating an electrical signal at high frequency and high voltage, which is modulated by a signal at lower frequency that is to be transformed into sound waves, a metal housing fixed detachably to the frame and forming with the latter a completely closed shielding that encloses said generating circuit, a metal horn of exponential form, which extends into the interior of the metal housing and whose output end opens through an opening in the housing, and a corona-effect transducer consisting of a tube made of an electrically insulating material, resistant to high temperature, which is mounted at the input of the exponential horn and in the bore of which there extends a discharge electrode connected electrically to the output of said generating circuit and having a tip disposed in proximity to the input end of the horn, said horn having, at its input end, a cylindrical accommodation coaxial to the longitudinal axis of the horn, said housing having a cylindrical passage which is axially spaced and aligned with the said cylindrical accommodation, said transducer being in the form of a cylindrical cartridge which is mounted slidably in the said passage of the housing and one end of which is engaged in the said accommodation while its other end projects beyond the outer end of the said passage, said electrode having a cylindrical contact part exposed in an intermediate zone of the cylindrical surface of the cartridge-shaped transducer, between the cylindrical accommodation and the inner end of the said passage, a metal contact means which is connected electrically to the output of said generating circuit and is in sliding contact with said cylindrical contact part of the electrode, and a metal plug which is fixed detachably to the outer end of the said passage and holds said cartridge-shaped transducer axially in place.