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:
Mar. 22, 1994
Filed:
Apr. 12, 1993
Daniel L Olds, Bryan, OH (US);
Sandra Snyder, Bryan, OH (US);
SPX Corporation, Muskegon, MI (US);
Abstract
Apparatus for identifying and distinguishing between at least two types of refrigerant that includes a fixed volume for containing a refrigerant sample at controlled vapor pressure. A thermistor provides a first electrical signal as a function of the combined effect of thermal conductivity and temperature of a refrigerant sample in the sample-containing volume, and a temperature sensor provides a second electrical signal as a function of temperature of the refrigerant vapor in the sample-containing volume essentially independent of thermal conductivity thereof. Associated electronics determines type of refrigerant in the sample-containing volume as a function of the first and second electrical signals, and thus as a function of thermal conductivity of the refrigerant sample independent of sample temperature. Since thermal conductivity of refrigerants at a given temperature and pressure varies for different refrigerant types, refrigerant type can be determined and displayed to an operator.