04823788 is referenced by 132 patents and cites 4 patents.

An improved method and apparatus for controlling the flow of any breathing gas such as oxygen through a cannula or "mask" to a person (patient, aviator, baby, miner, or diver) can be limited to the portion of the breathing cycle when the person breathes inward. This has the effect of reducing the consumption of breathing gas to at least half and possibly less. The result of this reduction of consumption is an extended life of the gas supply and a reduction of the cost per unit time. A bidirectional dynamic mass flow sensor senses the rate of flow of a gas through it and yields an output voltage proportional to mass flow and direction of gas movement. The measured dynamic flow signal is applied to a system controller which operates a flow controller. The system controller provides for indications of operation such as system failure and apnea, rate of flow, duration of flow, and total consumption; in addition, controls are provided to set the duration of gas flow in each breathing cycle.

Demand oxygen controller and respiratory monitor
Application Number
Publication Number
Application Date
April 18, 1988
Publication Date
April 25, 1989
Robert G Irvine
1393 Carthage Ct., Claremont, 91711
Richard F M Smith
1571 Mulberry Ave., Upland, 91786
Walter F Wessendorf Jr
A62B 9/02
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