The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 22, 1989
Filed:
Mar. 11, 1987
Daniel W Knodle, Seattle, WA (US);
William E Crone, Redmond, WA (US);
Cascadia Technology Corporation, Redmond, WA (US);
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 across that stream of gases between the infrared radiation emitter and the infrared radiation detectors. The emitter and detectors are incorporated in a transducer head which can be detachably fixed to the airway adapter.