Compensated control valve

A temperature compensated electrically operated modulating valve, comprising:

• a valve including a shell, said valve having an inlet, an outlet and valve means for regulating fluid flow between said inlet and said outlet;
• electrically energizable means for controlling the operating position of said valve means, said electrically energizable means including heater means mounted within said shell, said heater means comprising a first insulative surface, a second insulative surface and a resistive heater interposed between said first and said second surfaces, said heater means being flexible and folded to define receptacles for receiving a plurality of bimetallic discs interleaved between folds of said heater means;
• sensing means mounted to at least one of said bimetallic discs for sensing the temperature of said electrically energizable means, the temperature of said electrically energizable means being dependent upon the temperature of said heater means, the temperature of the fluid passing between the inlet and outlet of the valve, and the ambient temperature of the valve;
• and
• means for regulating power input to said electrically energizable means operatively connected to said sensing means, said regulating means adjusting the power input to said heater means to control the position of said valve means, said input power regulating means comprising a summing amplifier having a first input and a second input, said first input being electrically connected to a reference signal source, the second input being electrically connected to said sensing means, said summing amplifier having an output operatively connected to said electrically energizable means.