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. 30, 1977
Filed:
Aug. 16, 1976
Frank X McNally, Venetia, PA (US);
CSE Corporation, Monroeville, PA (US);
Abstract
This is an improvement in apparatus for detecting combustible gases, such as methane, that embodies a Wheatstone bridge circuit including a refractory-coated reference element constituting one leg of the bridge and a refractory-coated detector element having thereon a catalyst for promoting oxidation of the combustible gas to be detected constituting a second leg of the bridge. Upon oxidation of combustible gas at the detector element the temperature and resistance thereof increases relative to the reference element to unbalance the bridge, thereby producing an electrical signal proportional to the amount of combustible gas being oxidized. This invention improves the stability, linearity, and stabilization time of the bridge signal by constructing the reference element so that at zero percent combustible gas or during oxidation of the combustible gas at the detector element the radiant energy of both the detector and reference element are substantially equal.