Patent ID: 6533656
Filing Date: 2003-03-18
Classification: F24F

Abstract:
An air duct vent closure device for an HVAC duct vent defining an opening for at least one of introduction to and withdrawal of air from a room, the duct vent closure device comprising:a door having a counterweight oppositely disposed about and supported by a hinge axis positioned adjacent the duct vent opening, the hinge axis is delineated by a first and second hinge pins linearly arranged and rotatably supporting the door; a closed position wherein the counterweight influences the door into sealable contact with the duct vent opening to block air flow there through; an open position wherein a positive pressure induced by the HVAC system overcomes the influence of the counterweight, causing the door to disengage from sealable contact with the opening and allow air flow there through; the door further comprises an outer edge providing sealable contact with the duct vent in the close position, the outer edge also having a first and second hinge pin engagement apertures for rotatably engaging the first and second hinge pins to provide rotatable engagement of the door and counterweight about the hinge axis; and wherein the duct vent opening is located substantially in a plane defined by a ceiling of the room and the door in the closed position is substantially co-planer with the ceiling plane and sealably covers the duct vent opening due to the influence of the counter weight providing a biasing leverage to the door about the hinge axis, the counterweight being positioned and moveable in the room immediately below the ceiling plane; and the door is shaped as an air foil, the front portion of the door defining a leading edge of the air foil and the trailing portion defining a trail edge of the air foil.