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:
Oct. 12, 1976
Filed:
Aug. 04, 1975
Paul Vincent Guido, Cedar Grove, NJ (US);
Robert Lenox Criswell, Florham Park, NJ (US);
Foster Wheeler Energy Corporation, Livingston, NJ (US);
Abstract
There has been provided a control for regulating the pressure excursions in a furnace having forced draft and induced draft fans. A pressure detector responsive to pressure in the furnace delivers an output indicative thereof. Circuit means, responsive to the pressure detector means and a set point input, delivers a correction signal output. Fan control means coupled to the induced draft fan is responsive to a demand input signal corresponding to a desired flow rate through the furnace and is likewise responsive to the correction signal for delivering a fan control signal for regulating said induced draft fan in accordance with variations in the flow rate and pressure excursions in the furnace. An override circuit is responsive to the pressure detector and an override set point input to produce an override output for controlling the induced draft fan at a rate substantially higher than that of the correction signal. There is also provided a transfer and memory circuit responsive to combustion air flow to the furnace and a furnace trip condition such that the circuit produces a signal to modify said fan control signal in accordance with the actual air flow to the furnace and in anticipation of an inevitable furnace pressure excursion caused by said furnace trip.