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. 15, 1991
Filed:
Nov. 21, 1990
Lance J Evens, Carrollton, TX (US);
Other;
Abstract
A furnace comprises a housing, a fan or blower for moving air through housing, a burner in the housing, fuel supply means operatively connected to the burner, a heat exchanger in the housing a combustion chamber, the burner cooperating with said combustion chamber, an enclosure enclosing the heat exchanger and burner, said enclosure having an opening therein, and a damper operable to control the flow of air through said opening to the heat exchanger. The damper comprises a plate member pivotally mounted in the housing for opening and closing said opening. Preferably a drive motor opens the plate member and a spring biases the plate member closed. The damper is closed when the burner is off and is open when the burner is on. There is a circuit associated with the fuel supply means which is responsive to a predetermined open position of the plate member for permitting the flow of fuel through the fuel supply means when the plate member is open to said predetermined open position. A pilot hole is provided in the plate member for supplying limited air to said burner to maintain combustion for a pilot flame.