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:
May. 28, 1996
Filed:
Sep. 23, 1994
William Glaunsinger, Chandler, AZ (US);
Ian Sorensen, Phoenix, AZ (US);
Mahesan Chelvayohan, El Torro, CA (US);
Arizona Board of Regents, Tempe, AZ (US);
Abstract
A combustible gas sensor having a noble metal sensor element with a surface that is heated above a critical temperature at which the surface is able to dissociate oxygen in a gas stream and adsorb the oxygen onto its surface. The adsorbed oxygen present on the noble metal surface enhances the reactivity of the sensor element and permits it to react with combustible gases that otherwise would have little or no affinity for the sensor element. The balance of adsorbed oxygen and combustible gas species on the sensor surface cause a change in an electrical property that is used to determine the presence or identity of a combustible gas, or to derive a concentration measurement. The electrical property measured to determine the presence, identity, or concentration of combustible gas includes the work function of the noble metal surface, which may be measured by incorporating the sensor element as a component of a variable capacitor contained in an electrical circuit adapted to measure change in current caused by the change in capacitance of the variable capacitor.