Patent ID: 6447393
Filing Date: 2002-09-10
Classification: A62C

Abstract:
A powered damper assembly mounted within a duct, comprising:a butterfly damper, further comprising: a damper frame; and damper blades pivotally attached to the damper frame such that the damper has an open position to allow air flow therethrough and a closed position to prevent air flow through the damper frame; a powered actuator cycling means attached to the damper, comprising a pneumatic actuator having a shaft means axially movable within the duct toward and away from the blades in response to pneumatic pressure changes; a source of pneumatic pressure connected to the pneumatic actuator; means to change the level of pneumatic pressure; and opposing pressure means set in opposition to the pneumatic pressure source and providing opposing pressure such that a change in the level of pneumatic pressure in relation to the opposing pressure means will result in axial movement of the movable shaft means; and said shaft means, attached at one end to the pneumatic actuator and attached at its other end to the damper blades, such that the powered actuator cycling means can move the shaft means axially and cause the damper blade to move and cycle between an open position and a closed position by varying the pneumatic pressure.