Powered damper having automatic static duct pressure relief

摘要

The damper includes a support housing which defines a flow passage which communicates the supply duct with the conditioned space. Damper blades are mounted within the support housing for pivotal movement about respective spaced apart parallel axes. A blade link interconnects the damper blades in a ganged relation so that a common pivoted orientation of the damper blades is determined by the position of the blade link. The blade link is movable to any position which lies between a first position where the damper blades cooperate with one another so that air flow through the passage is blocked and a second position wherein air flow through the passage is at a maximum. A force is selectively exerted on the blade link which will either move the link toward the second position to increase the flow of air through the damper or for exerting a force on the blade link to move the link toward the first position to decrease the flow of air through the damper. The blade link can move toward the second position (maximum flow) in response to a force imparted on the damper blades by a build-up of pressure in the supply duct.