Patent ID: 6161539
Filing Date: 2000-12-19
Classification: A61M

Abstract:
A lung ventilator safety valve for relieving pressure from a patient airway of a ventilator system, said safety valve comprising:a valve housing fluidly connected to a vent in the patient airway, said vent having a valve seat;a valve seal adjacent and parallel to the valve seat of the vent for allowing a relief flow from the vent in a valve open position and for sealing the vent in a valve closed position;a pilot spring urging said valve seal to the valve closed position to seal the vent, whereby said valve seal will move to the valve open position to allow the relief flow when pressure within the patient airway exceeds the biasing force of the pilot spring, to protect a patient from excess pressure in the patient airway;said valve seal being attached to a flexible diaphragm extending to the valve housing around the valve seal forming a chamber in the valve housing, a surface of the valve seal defining an aperture extending through the valve seal, whereby when there is relief flow through the safety valve vent, the relief flow across the flexible diaphragm creates a venturi effect resulting in a negative pressure on the opposing side of the diaphragm that biases the safety valve to open further.