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:
Sep. 21, 2010
Filed:
May. 12, 2005
Brent Chian, Plymouth, MN (US);
John T. Adams, Aran, CH;
Timothy J. Nordberg, Plymouth, MN (US);
Bruce Hill, Roseville, MN (US);
Peter M. Anderson, Minneapolis, MN (US);
Brent Chian, Plymouth, MN (US);
John T. Adams, Aran, CH;
Timothy J. Nordberg, Plymouth, MN (US);
Bruce Hill, Roseville, MN (US);
Peter M. Anderson, Minneapolis, MN (US);
Honeywell International Inc., Morristown, NJ (US);
Abstract
A system for adjusting a bias voltage of a flame sensing system. The system may use pulse width modulation to adjust the bias voltage. The system may have a flame sensing rod that conveys an electrical equivalent circuit of a flame presence to a detector via low pass filter. An excitation voltage may be conveyed via a DC blocking mechanism to the sensing rod. A pulse width modulation signal may be conveyed via a bias resistor to a node of the low pass filter and the detector. The input of an A/D converter may be that of the detector for flame signals. Also, leakages between the node of the A/D converter connection and the voltage source and/or ground may be detected and compensated. Further, leakage of the DC blocking mechanism may be minimized.