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. 22, 1990
Filed:
Sep. 28, 1989
Timothy J Shellenberger, Fort Smith, AR (US);
William T Harrigill, Fort Smith, AR (US);
Rheem Manufacturing Company, , US;
Abstract
To inhibit internal heat exchanger corrosion, the products of combustion from a standing pilot flame in an induced draft, fuel-fired furnace are prevented from migrating through the heat exchanger during idle periods of the furnace by flowing the products of combustion upwardly through a small vent tube into the outlet section of the draft inducer fan, and then into an external exhaust stack, thereby bypassing the heat exchanger. During operation of the draft inducer fan a negative pressure is maintained within the vent tube, to prevent combustion gas outflow therethrough which might otherwise snuff out the pilot flame, by a venturi structure positioned within the draft inducer fan outlet section adjacent its juncture with the vent tube.