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. 09, 2000
Filed:
Jun. 24, 1997
Joseph DiTucci, Simsbury, CT (US);
Stephen K Phelps, Chillicothe, IL (US);
Martin F Zabielski, Manchester, CT (US);
Gas Research Institute, Chicago, IL (US);
Abstract
A fail safe gas furnace optical flame sensor uses a transconductance amplifier with low photodiode current to sense the presence or absence of a gas flame within the burner of a gas furnace. The photodiode signal appears as the only negative voltage signal in the circuit, and the equivalent resistance feedback network is redundantly designed, thus ensuring that no false flame-on conditions will be detected due to the failure of a single resistive component. Because it does not reside within the flame, the sensor is immune to false flame-off conditions caused by material deposition and corrosion of the sensor.