Practica oto-rhino-laryngologica. Suppl.

Show abstractHide abstract

Many aspects of the vibratory mechanism of the rubber membrane of the pneumatic artificial larynx are still unknown. The investigation of this mechanism is essential to the improvement and the effective use of the pneumatic artificial larynx. With the use of a blowing apparatus which contained an air compress o r at its air source, the air flow rate and the pressure inside the pneumatic artificial larynx were measured as input parameters, and the sound pressure level and the fundamental frequency outside the pneumatic artificial larynx were measured as output parameters. The vibratory pattern of the rubber membrane was photographed with a stroboscope.
(1) The increase of input power needed for the increase of fundamental frequency (Δ input power/Δ Hz) differed corresponding to the frequency range, and the whole blowing range could be divided into four subranges (A-D). (2) The rubber membrane showed four different vibratory patterns corresponding to the subranges. (3) Changes of the vibratory pattern caused changes in the tension of the rubber membrane and in the fundamental frequency. (4) Differences in the shape of the resonance cavity influenced the vibratory pattern of the rubber membrane of the pneumatic artificial larynx which resulted in different articulation scores of various speech sounds.

View full abstract

Download PDF (26554K)

Register with J-STAGE for free!