Patent ID: 6435211
Filing Date: 2002-08-20
Classification: F16K,F24F,Y10T

Abstract:
A damper apparatus for controlling gas flow in a duct, comprising:inner walls defining a gas-confining inner channel between inlet and outlet openings; a closure operable between an open position and a closed position, said closure comprising: a blade formed of first, second, third and fourth elongate panels, each panel having opposed hinged edges; four parallel hinge pins connecting hinge edges of the panels in a quadrilateral wherein each panel is rotatable relative to adjacent connected panels; a stationary hingepin with opposed ends, said stationary hingepin connecting first hinged edges of said first panel and said second panel, said stationary hingepin having its ends mounted in opposing inner walls; a first floating hingepin connecting second hinged edge of said first panel and first hinged edge of said third panel; a second floating hingepin connecting second hinged edge of said second panel and first hinged edge of said fourth panel; a drive hingepin connecting second hinged edges of said third panel and said fourth panel; whereby said panels form a quadrilateral with four exterior angles between adjacent panels; and drive means communicating with said drive hingepin for driving said drive hingepin to move said closure between said open position and said closed position; wherein in said closed position, the exterior angle between said third and fourth panels is less than 180 degrees.