Automatic energy saver and fire damper for exhaust systems

摘要

Exhaust system control apparatus operative to automatically close a damper in an exhaust duct leading from a spray booth when the spray booth is not in operation. A reversible damper motor is energized to rotate the damper to an open position when the spray booth is in operation. The damper motor is automatically reversed to close the damper in response to termination of spray booth operation. Energy is thus conserved by reducing the amount of heated air that would otherwise escape through the exhaust duct when the spray booth is not being used. In case of fire, the same damper is automatically rotated to a closed position in the exhaust duct by a spring loaded sprocket assembly on the damper shaft. This safety action takes place in response to the melting of a fusible link located in the exhaust duct and connected to a sprocket retention cable.