Gas-dispensing device with self-contained gas container having a diffusion membrane
View Patent ↗A gas-dispensing device ( 2 ) for dispensing a gas into breathing gas, comprising a membrane ( 6 ) through which the gas can diffuse into the breating gas, is described. The gas-dispensing device ( 2 ) is simple and reliable because it contains a self-contained chamber ( 4 ) in which the gas is held at a predefined overpressure, and the membrane ( 6 ) is arranged to form a part of the chamber's ( 4 ) wall.
1. A gas dispensing device for dispensing a gas into a breathing gas, comprising:
a self-contained chamber charged with a gas to be dispensed and sealed to maintain said gas at a predetermined overpressure; and
a membrane through which said gas can diffuse into breathing gas due to said overpressure, said membrane forming a part of a wall of said self-contained chamber and, after charging of said self-contained chamber with said gas to be dispensed, said self-contained chamber having no ingress or egress for said gas other than said membrane; and
a pressure device for maintaining pressure in said chamber during dispensing of said gas.
2. A gas dispensing device as claimed in claim 1 comprising a cover for said membrane, allowing said gas to be dispensed only upon removal of said cover.
3. A gas-dispensing device as claimed in claim 2 wherein said cover is variable in size, to selectively cover different portions of said membrane to selectively set an amount of said gas dispensed through said membrane.
4. A gas-dispensing device as claimed in claim 1 wherein said chamber contains a donor substance in said gas.
5. A gas dispensing device as claimed in claim 1 further comprising a refill arrangement in communication with said chamber allowing said chamber to be refilled.
6. A breathing apparatus comprising:
a source of breathing gas; and
a gas dispensing device disposed to interact with said source of breathing gas, said gas dispensing device comprising a self-contained chamber charged with a gas to be dispensed and sealed to maintain said gas at a predetermined overpressure, and a membrane through which said gas can diffuse into breathing gas, said membrane forming a part of a wall of said self-contained chamber and, after charging of said self-contained chamber with said gas to be dispensed, said self-contained chamber having no ingress or egress for said gas other than said membrane; and
a pressure device for maintaining pressure in said chamber during dispensing of said gas.
7. A breathing apparatus as claimed in claim 6 comprising an inspiratory passage, and wherein said gas dispensing device is disposed in said inspiratory passage.
8. A breathing apparatus as claimed in claim 6 comprising a patient connector, and wherein said gas dispensing device is disposed in said patient connector.