FLUID VALVE ASSEMBLY AND PROCESS VALVE POSITIONER Russian patent published in 2019 - IPC F16K11/02 F16K31/126 F15B13/42 

FIELD: machine building.

SUBSTANCE: disclosed is a process valve positioner comprising an electronic unit having an electrical control output, and a pneumatic or hydraulic unit comprising a preliminary stage and an output stage, wherein preliminary stage is configured to convert electric control signal from said output to initial fluid pressure, which is sufficient to control output stage, wherein output stage comprises fluid valve assembly for connection with pressurized fluid source for application to hydraulic or pneumatic actuator of actuator fluid medium pressure, wherein valve assembly of fluid medium comprises: valve body having a central hole with at least one supply opening for receiving a portion of fluid medium under pressure, at least one actuator outlet to apply actuator fluid pressure to the hydraulic or pneumatic actuator and at least one outlet; a rod moved inside said central hole in axial direction by an axial initial force; an initial exposure diaphragm and a piston located at one end of the stem, providing an axial initial force in accordance with the initial fluid pressure acting on the initial exposure diaphragm and the piston in the initial pressure chamber; counteracting diaphragm and counteracting piston located at the opposite end of the rod, providing a counter force opposite to the axial initial force and corresponding to the fluid counter pressure acting on the counter-pressure diaphragm in the counter-pressure chamber; at least one pair of counter-acting dispensing edges, functionally connected to each other by means of a rod, wherein each dispensing edge of each pair of counter action comprises a mating seating surface on valve or rod body and annular plate resting by means of flexible element on valve body or rod so as to provide relative axial movement of annular plate and supporting body of valve or stem also in closed state of corresponding dispensing edge, each annular plate is balanced by pressure to compensate for fluid pressure forces applied to the corresponding annular plate, and to thereby obtain a very low or zero resultant force of fluid pressure acting on the corresponding metering edge; limited flow path from inlet of valve assembly pressure to preliminary stage to control initial pressure in initial pressure chamber and thus the axial initial force and the additional flow of the restricted flow from the input of the supplied pressure of the valve assembly to the counter-pressure chamber.

EFFECT: fluid medium valve assembly and process valve positioner are described.

11 cl, 21 dwg