Patent ID: 7179165

Claim:
An automatic vent damper, comprising: a housing having at least one vent door opening defined therein, the opening having at least an upper edge and a lower edge opposite the upper edge; at least one rigid, aerodynamic vent door having at least an upper edge and a lower edge opposite the upper edge, the door being pivotally disposed over the at least one vent door opening, wherein: said at least one aerodynamic vent door has a downwardly facing positive camber when in an open position, whereby wind flow entering the at least one vent door generates an aerodynamic force drawing said at least one vent door automatically closed; and said at least one aerodynamic vent door further has an outwardly facing concave face when in a closed position, whereby wind flow contacting the concave face holds said at least one vent door automatically in a closed position, the outwardly facing concave face having a concave contour extending over the entire outwardly facing concave face; a vent door attachment disposed at the upper edge of the at least one vent door opening, pivotally securing the upper edge of said vent door to said housing; and at least one spring connected between said at least one vent door and said housing, automatically biasing said at least one vent door open in wind conditions less than a predetermined velocity and direction relative to the vent door opening and the spring constant of said at least one spring and automatically allowing said at least one vent door to blow to a closed position when the wind reaches a predetermined velocity and direction relative to the vent door opening and the spring constant of said at least one spring.