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:
Nov. 09, 1993
Filed:
Jun. 12, 1992
Glenn M Tom, New Milford, CT (US);
Novapure Corporation, Danbury, CT (US);
Abstract
An endpoint detector for gas purifiers which contains a detection element comprising a small amount of a highly reactive metal coated on an insulator and exposed to the gas stream being purified. This metal does not react with the gas being purified, but does undergo reaction with the impurity species. As this metal reacts with impurities in the gas stream, its conductivity decreases. The change in conductivity signals that the wave front of impurity-containing gas has reached the sensor, and thus the purifier has reached the end of its useful life. The use of a thin coating of reactive metal as the detection element gives the sensitivity that is required to sense sub-part-per-million levels of impurities. This resistance change sensor may be combined with a thermal measurement to detect the presence of exothermic conditions indicative of a large pulse of impurity gas.