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:
Jun. 26, 2007
Filed:
Oct. 08, 2003
Peter John Smith, Oxon, GB;
Keith Francis Edwin Pratt, Oxon, GB;
Peter John Smith, Oxon, GB;
Keith Francis Edwin Pratt, Oxon, GB;
City Technology Limited, Portsmouth, GB;
Abstract
A method of detecting a predetermined alarm condition in a combustion emission gas. The method comprises exposing to the gas a semiconductor gas sensor having a p-type mixed metal oxide semiconducting material of the first, second and/or third order transition metal series, the semiconducting material being responsive both to a change in concentration of a reducing gas in the surrounding atmosphere and to a change in concentration of oxygen in the surrounding atmosphere to exhibit a change in its electrical resistance. The resistance is monitored and an alarm signal is output if the resistance exceeds a predetermined value corresponding to the alarm condition.