A passenger service unit assembly that includes a frame that defines at least an oxygen opening and a service opening, an oxygen mask housing positioned adjacent the oxygen opening, an oxygen mask housing cover positioned to cover the oxygen opening, and a service cover positioned to cover the service opening. An oxygen mask that is movable between a stowed position and a deployed position is positioned in the oxygen mask housing. The oxygen mask housing cover maintains the oxygen mask in the stowed position. The oxygen mask housing cover is movable between a closed position and an open position. When the oxygen mask housing cover is moved to the deployed position, the oxygen mask drops to the deployed position via gravity. The service cover is movable between a closed position and an open position and includes at least a first passenger service unit component associated therewith.

A passenger service unit assembly that includes a frame that defines at least an oxygen opening and a service opening, an oxygen mask housing positioned adjacent the oxygen opening, an oxygen mask housing cover positioned to cover the oxygen opening, and a service cover positioned to cover the service opening. An oxygen mask that is movable between a stowed position and a deployed position is positioned in the oxygen mask housing. The oxygen mask housing cover maintains the oxygen mask in the stowed position. The oxygen mask housing cover is movable between a closed position and an open position. When the oxygen mask housing cover is moved to the deployed position, the oxygen mask drops to the deployed position via gravity. The service cover is movable between a closed position and an open position and includes at least a first passenger service unit component associated therewith.

A breathing regulator including a first stage regulator, a second stage regulator, a dilution valve, a mixing chamber, and a controller is provided. The first stage regulator is in fluid communication with pressurized source gas. The second stage regulator is in fluid communication with the first stage regulator. The dilution valve is in fluid communication with an ambient gas and includes a size-variable restriction. The mixing chamber is in fluid communication with the second stage regulator, the dilution valve, and a breathing cavity. The controller is in electrical communication with the dilution valve, the second stage regulator, and a plurality of sensors. The controller is configured to: determine a mass flow of the source gas; determine mass flow of the ambient gas; and vary the size-variable restriction of the dilution valve based on the mass flow of the source and/or the mass flow of the ambient gas.

A breathing regulator including a first stage regulator, a second stage regulator, a dilution valve, a mixing chamber, and a controller is provided. The first stage regulator is in fluid communication with pressurized source gas. The second stage regulator is in fluid communication with the first stage regulator. The dilution valve is in fluid communication with an ambient gas and includes a size-variable restriction. The mixing chamber is in fluid communication with the second stage regulator, the dilution valve, and a breathing cavity. The controller is in electrical communication with the dilution valve, the second stage regulator, and a plurality of sensors. The controller is configured to: determine a mass flow of the source gas; determine mass flow of the ambient gas; and vary the size-variable restriction of the dilution valve based on the mass flow of the source and/or the mass flow of the ambient gas.

There is provided an apparatus for preparing a ventilation gas mixture for pilots and crew of aircraft, the apparatus comprising a first gas mixer feed configured to receive exhaled air from a person, wherein the exhaled air comprises carbon dioxide, a second gas mixer feed configured to receive an air mixture comprising at least one gas, and a gas mixing device configured to receive the exhaled air and the air mixture from the first and second gas mixer feeds and combine the exhaled air with the air mixture in the gas mixing device to form a ventilation gas mixture. The apparatus further comprises a pressure adjuster configured to increase the pressure of the exhaled air in the first gas mixer feed so that it substantially matches the pressure of the air mixture in the second gas mixer feed.

There is provided an apparatus for preparing a ventilation gas mixture for pilots and crew of aircraft, the apparatus comprising a first gas mixer feed configured to receive exhaled air from a person, wherein the exhaled air comprises carbon dioxide, a second gas mixer feed configured to receive an air mixture comprising at least one gas, and a gas mixing device configured to receive the exhaled air and the air mixture from the first and second gas mixer feeds and combine the exhaled air with the air mixture in the gas mixing device to form a ventilation gas mixture. The apparatus further comprises a pressure adjuster configured to increase the pressure of the exhaled air in the first gas mixer feed so that it substantially matches the pressure of the air mixture in the second gas mixer feed.

Oxygen-delivery systems are described. The systems may supply emergency respiratory gas on demand to aircraft passengers. To reduce risk of blockage of tubes delivering anti-blocking gas to the face masks worn by the passengers, the systems may be designed to provide a continuous trickle flow of respiratory gas, or one or more anti-blocking pulses of gas, into a delivery tube.

Oxygen-delivery systems are described. The systems may supply emergency respiratory gas on demand to aircraft passengers. To reduce risk of blockage of tubes delivering anti-blocking gas to the face masks worn by the passengers, the systems may be designed to provide a continuous trickle flow of respiratory gas, or one or more anti-blocking pulses of gas, into a delivery tube.

Systems and methods for emergency breathing systems in accordance with embodiments of the invention are disclosed. In an embodiment, a second stage regulator includes a housing, a first nosepiece coupled to a first lever, a second nosepiece coupled to a second lever, a first spring located in the housing and coupled to the first nosepiece and the first lever, a second spring located in the housing and coupled to the second nosepiece and the second lever, a mouthpiece, and a coupler coupled to the housing, wherein the first spring and the second spring bias the first nosepiece and the second nosepiece towards each other.

The invention relates to an emergency oxygen device for passenger of an aircraft, including a chemical oxygen generator including a chemical oxygen source and an activation unit for initiating a chemical reaction of the chemical oxygen source producing oxygen, at least two oxygen masks each connected with the chemical oxygen generator for receiving an oxygen fluid flow from the chemical oxygen generator after the activation unit has initiated the chemical reaction, and a mechanical activation assembly for activating the activation unit. The activation unit is activated by a mechanical force exerted onto an activation element of the activation unit and the mechanical activation assembly includes for each of the at least two oxygen masks a first mechanical connection from the activation element to a fixation element releasably mounted to the emergency oxygen device and a second mechanical connection from the fixation element to the oxygen mask.