Fluid flow control damper

摘要

A damper is provided which is adapted to be positioned in a building conduit to control the flow of fluid through the conduit. The damper includes a frame and barrier structure coupled to the frame which is movable between open and closed positions. The barrier structure permits fluid to flow through the conduit when positioned in the open position and substantially blocks fluid flow through the conduit when positioned in the closed position. The damper further includes an actuator which is coupled to the barrier structure for effecting movement of the barrier structure. A control circuit is also provided and is connected to the actuator for controlling the operation of the actuator. The control circuit includes a thermal responsive switch which, preferably, is located outside of the conduit. The thermal responsive switch prevents operation of the actuator when the temperature of fluid surrounding the switch exceeds a first predetermined value.