Respiratory valve apparatus

A respiratory valve apparatus for delivering a pressurised flow of breathable gas to the airway of a user, comprising:

• a valve body comprising an inlet port configured to receive the breathable gas, an outlet port configured to release the breathable gas to the user's airway during an inhalation phase and to receive exhaled gas during an exhalation phase of a respiratory cycle of the user, a breathable gas flow passage communicating between the inlet and outlet ports, an exhaust port for releasing the exhaled gas, and an exhaled gas flow passage communicating between the outlet and exhaust ports;
• the exhaust port defining a plurality of substantially parallel slots spaced circumferentially around the valve body at the exhaled gas flow passage, the slots being staggered in length;
• a first valve located in the breathable gas flow passage and being configured under the pressurised flow of breathable gas from the inlet port to open the breathable gas flow passage during the inhalation phase to enable flow of the breathable gas to the user, and to close the breathable gas flow passage during the exhalation phase;
• a second valve located in the exhaled gas flow passage and including a flexible membrane that defines an internal cavity, the flexible membrane being configured to close the exhaust port under ambient pressure and during the inhalation phase and to at least partially open the exhaust port during the exhalation phase;
• an equilibrium passage disposed between an upstream side of the first valve and the internal cavity of the second valve and being configured, under the pressurised flow of breathable gas from the inlet port, to divert part of the breathable gas to the internal cavity of the flexible membrane via the equilibrium passage to ambient pressure and to maintain the exhaust port closed during the inhalation phase.

A respiratory valve apparatus for delivering a pressurised flow of breathable gas to the airway of a user, comprising:

• a valve body comprising an inlet port configured to receive the breathable gas, an outlet port configured to release the breathable gas to the user's airway during an inhalation phase and to receive exhaled gas during an exhalation phase of the user's respiratory cycle, a breathable gas flow passage communicating between the inlet and outlet polls, an exhaust port configured to release the exhaled gas, and an exhaled gas flow passage communicating between the outlet and exhaust ports;
• the exhaust port defining a plurality of substantially parallel slots spaced circumferentially around the valve body at the exhaled gas flow passage, each of the slots being longitudinally tapered in thickness and progressively narrower in an upstream direction;
• the exhaust port comprising a plurality of substantially parallel slots spaced circumferentially around the valve body, the slots being staggered in length at the exhaled gas flow passage;
• a first valve located in the breathable gas flow passage and being configured, under the pressurised flow of breathable gas from the inlet port, to open the breathable gas flow passage during the inhalation phase to enable flow of the breathable gas to the user, and to close the breathable gas flow passage during the exhalation phase;
• a second valve located in the exhaled gas flow passage and comprising a flexible membrane defining an internal cavity, the flexible membrane being configured, under ambient pressure and during the inhalation phase, to close the exhaust port and, during the exhalation phase to at least partly open the exhaust port;
• an equilibrium passage disposed between an upstream side of the first valve and the internal cavity of the second valve and being configured, under the pressurised flow of breathable gas from the inlet port, to divert part of the breathable gas to the internal cavity of the flexible membrane via the equilibrium passage to ambient pressure and, during the inhalation phase, maintain the exhaust port closed.

A respiratory valve apparatus for delivering a pressurised flow of breathable gas to the airway of a user, the respiratory valve apparatus comprising:

• a valve body including an inlet port for receiving the breathable gas, an outlet port for releasing the breathable gas to the user's airway during an inhalation phase and for receiving exhaled gas during an exhalation phase of the user's respiratory cycle, a heat and moisture exchange element coupled to the outlet port to transfer moisture to the breathable gas, a breathable gas flow passage communicating between the inlet and outlet ports, an exhaust port for releasing the exhaled gas, and an exhaled gas flow passage communicating between the outlet and exhaust ports;
• a first valve located in the breathable gas flow passage and being operable under the pressurised flow of breathable gas from the inlet port to open the breathable gas flow passage during the inhalation phase to enable flow of the breathable gas to the user, and to close the breathable gas flow passage during the exhalation phase;
• a second valve located in the exhaled gas flow passage and including a flexible membrane defining an internal cavity, the flexible membrane being operable to seal the exhaust port under ambient pressure and during the inhalation phase and to at least partly expose and open the exhaust port during the exhalation phase;
• an equilibrium passage disposed between an upstream side of the first valve and the internal cavity of the second valve and being operable under the pressurised flow of breathable gas from the inlet port to divert part of the breathable gas to the internal cavity of the flexible membrane via the equilibrium passage and to maintain the exhaust port closed during the inhalation phase.