Using the stator to prevent valve seat turning

In an electromagnetically operated valve which comprises a valve body, a valve seat member having an axis and being received in a mounting in said body such that said seat member can potentially turn within said mounting about said axis, said valve seat member also comprising a frusto-conical seat as a surface of revolution about said axis, a sphere that is disposed for co-action with said seat to open and close flow through the valve, resilient means acting to resiliently urge said sphere along said axis toward concentrically seating on said seat and thereby closing flow through the valve, and sphere-actuating means, including electromagnetic operating means, for bodily displacing said sphere from concentric seating on said seat comprising a movable bar that is disposed along side said sphere and operated by said electromagnetic operating means to execute motion that is predominantly along the direction of an imaginary line that intersects said axis, said bar executing such motion toward and away from said axis in accordance with a control signal applied to said electromagnetic operating means, such motion of said bar toward said axis creating a force acting on said sphere at the end of a radial of said sphere, which radial, when viewed along said axis, is substantially coincident with said imaginary line, and such force created by such motion of said bar along said imaginary line being effective, in cooperation with said seat and resilient means, to cause said sphere to be bodily displaced from concentricity with said axis to eccentricity with said axis thereby opening flow through the valve, and such motion of said bar away from said axis being effective to allow said resilient means, in cooperation with said seat, to cause said sphere to be restored to concentricity with said axis and thereby close flow through the valve, the improvement in which said sphere-actuating means comprises a stator that in cooperation with said bar forms a magnetic circuit and that has a termination confronting said bar across a gap via which magnetic force is delivered to operate said bar, and in which between said stator and said seat member there is provided means creating an interference causing said stator to constrain said seat member against turning within said mounting about said axis.