There is provided a method of manufacturing a torsion spring, comprising providing a section of sheet metal, and forming the torsion spring from the section of sheet metal.

A digitally controlled current to pressure converter (CPC) and method of controlling same is provided. The method of controlling includes the step of periodically imparting symmetrically-opposed movement of a control valve of the CPC to loosen and flush accumulated silt therefrom. More particularly, the method may include the step of periodically introducing a small-amplitude symmetrically-opposed impulse to a controller that actuates a hydraulic control shaft of a three-way rotary valve. Also provided is a method of preventing malfunction due to faulty input or feedback signals received by the CPC, and a method of detecting the health status of multiple CPCs when used in a redundant configuration.

There is provided a method of manufacturing a torsion spring, comprising providing a section of sheet metal, and forming the torsion spring from the section of sheet metal.

A digitally controlled current to pressure converter (CPC) is provided. A digital CPC utilizes a digital controller and an onboard pressure transducer to accurately control the output pressure based upon an input analog control signal. The digital controller includes an anti-silting algorithm that provides an impulse movement of the three-way rotary valve of the CPC to loosen and flush away silt contamination from the valve. A redundant seal stack including an intermediate passage to the hydraulic drain ensures a low pressure drop across the outboard seal minimizing the potential for leakage and improving reliability of the CPC. The digital controller also includes redundancy and fault management algorithms that enable the use of multiple inputs and feedback signals for control of the CPC. Master/slave operation and transitioning is also provided by the digital controller.

A hydraulic servovalve having two stages and feedback members in which the movable power distribution member has clamp means for clamping the feedback member, while allowing a clamped portion of the feedback member at least one freedom of movement relative to the movable distribution member.