Gas mixing apparatus for a ventilator
US6467478B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Feb 2, 2000 |
| Grant date | Oct 22, 2002 |
| Priority date | — |
| Expiry date | Feb 2, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M2016/102
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The gas mixing apparatus provides the components of a breathing gas for mixing at approximately ambient atmospheric pressure, and regulates the pressure of a selected gas to approximately ambient atmospheric pressure for mixing with air at ambient atmospheric pressure. The gas mixing apparatus includes a piston disposed within a pump chamber. A flow limiting inlet controls introduction of a first selected gas such as oxygen for mixing with a second selected gas such as air. The pressure of the first selected gas is limited to an acceptable maximum pressure, so that even if a valve for admitting the first selected gas for mixing at ambient pressure fails, breathing gas will not be provided at an excessive pressure. A demand valve is alternatively provided for reducing the pressure of the first selected gas supplied before mixing, but a pressure sensor is also provided downstream of the demand valve for detecting failure of the demand valve, to shut off the supply of the first selected gas to prevent overpressurization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.