POLYPHONE Russian patent published in 1997 - IPC

FIELD: medical equipment, can be used for diagnostic examinations. SUBSTANCE: polyphone has a casing, bell mouths that are opened and closed by a diaphragm, bell mouth selector switch, branch pipe connected to the auditory tubes through an acoustic line. The polyphone is furnished with an additional bell mouth, and additional longitudinal ducts are made in the head, installed at the end of the head is a selector switch in the form of a cup, whose walls envelop the cylindrical groove on the head housing. EFFECT: enhanced efficiency. 3 cl, 5 dwg