A mechanical insufflation/exsufflation apparatus (10) has a blower (14), a direction valve (28), an oscillator (30), and a mask hose connector (18). The blower (14) is connected to the direction valve(28), which is connected to the oscillator (30), which is connected to the hose connector (18). During insufflation, the direction valve (28) connects the blower exhaust (42) to the oscillator (30), causing positive pressure at the hose connector (18). During exsufflation, the direction valve (28) connects the blower intake (40) to the oscillator (30), causing negative pressure at the hose connector (18). The oscillator (30) is a butterfly valve with a 360° rotating disc (88). During insufflation, the disc (88) is fixed to steadily modulate the airflow. During exsufflation, the oscillator (30) is inactive or in flutter mode. When inactive, the disc (88) is fixed to allow maximum air flow. In flutter mode, the disc (88) continuously rotates so that the air flow rapidly alternates between maximum and minimum.Linvention concerne un équipement mécanique (10) dinsufflation/exsufflation qui comporte une soufflante (14), une vanne de sélection (28), un oscillateur (30), et un raccord (18) de tuyau souple de masque. La soufflante (14) est raccordée à la vanne de sélection (28), qui est raccordée à loscillateur (30), qui est raccordé au raccord (18) de tuyau souple. Pendant linsufflation, la vanne de sélection (28) raccorde léchappement (42) de la soufflante à loscillateur (30), provoquant une pression positive au niveau du raccord (18) de tuyau souple. Pendant lexsufflation, la vanne de sélection (28) raccorde ladmission (40) de la soufflante à loscillateur (30), provoquant une pression négative au niveau du raccord (18) de tuyau souple. Loscillateur (30) est une vanne papillon avec un disque (88) tournant sur 360°. Pendant linsufflation, le disque (88) est prévu pour moduler progressivement le débit dair. Pendant lexsufflation, loscillateur (30) est inactif ou en mode flotteme
