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:
Apr. 12, 1977
Filed:
Dec. 03, 1975
Martin Coiner Grostick, Goshen, IN (US);
Thomas Edward Hayes, Goshen, IN (US);
Johnson Controls, Inc., , US;
Abstract
A stack damper control arrangement for use in a heating system including a furnace having a fuel-fired burner apparatus and a vent stack for conducting combustion products away from the burner apparatus and a damper plate pivotally mounted within the stack and movable between a fully open and a fully closed position, includes a reversible drive motor which is energizable in response to a request for heat to drive the damper plate to the open position, a first limit switch operated when the damper plate reaches the open position to effect the deenergization of the motor, the motor being reenergized at the end of the heating cycle to drive the damper plate to the closed position, and a second limit switch operated when the damper plate reaches the closed position to effect the deenergization of the motor. The damper control arrangement is described with reference to a heating system including a gas fired burner and redundant gas valves wherein operation of a first one of the gas valves is effected through operation of the first limit switch and thus is conditional upon the damper being fully open, and wherein the supply of fuel to the second valve is conditional upon the operation of the first valve.