Gas analyzers
US4859859A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1987 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Mar 11, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/1218
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Gas analyzers of the non-dispersive infrared radiation type which are designed to measure the concentration of one gas in a mixture of gases containing that gas. A novel, electrically modulated, stable, thick film infrared radiation emitter is employed to emit a beam of collimated, focused energy; and two electrically biased detectors are preferably used so that a ratioed, error eliminating output signal can be supplied to the failsafe, signal processing circuitry of the analyzer. The latter, and a conventional analog-to-digital convertor, supply information to a microcomputer which: (1) turns the infrared radiation emitter on and off; (2) controls a heater which keeps the infrared radiation detectors at a constant, precise temperature; and (3) controls displays of a variety of information concerning the gas being measured and the status of the gas analyzer. The microcomputer also accepts ambient temperature, barometric pressure, and other compensation factors. Typically, a disposable airway adapter will be included in the gas analyzer to confine the mixture of gases being analyzed to a path having a transverse dimension of precise and specific length and to provide an optical path…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.