Patent ID: 6729844
Filing Date: 2004-05-04
Classification: F04D

Abstract:
An electronic control device for opening and closing valves in a valve assembly that actuates a variable pitch fan system capable of operating in a plurality of fan blade pitch positions comprising:a temperature switch actuated in response to a temperature condition of the engine; a pressure switch in series with said temperature switch and actuated in response to a pressure condition of the variable pitch fan system; a time delay relay control in parallel with said temperature switch and said pressure switch for transmitting a timed signal therefrom; a first solenoid in series with said pressure switch; a second solenoid in series with said time delay relay control and connected to said first solenoid; and wherein transmission of at least one of said timed signal, said temperature condition signal, and said pressure condition signal opens or closes the valves of the valve assembly of the variable pitch fan system.