Patent ID: 8235354

Claim:
A regulating valve for regulating the flow of fluid in refrigeration systems, comprising a valve body that has an inlet and an outlet for fluid, said inlet and said outlet being mutually connected by a connecting opening, a flow control device for said connecting opening, which is inserted in a seat formed in said valve body, said flow control device comprising an electric motor and a flow control piston, said electric motor being functionally connected to said flow control piston for axial controlled movement thereof along a sliding axis, between an open position and a blocking position of said connecting opening, said flow control piston having connection openings for connection between a front face thereof, which is directed toward said connecting opening, and a rear face thereof for balancing pressures applied by the fluid to said front face, said flow control piston having a head dome that faces said connecting opening and forms said front face, said connection openings comprising a plurality of mutually separate cylindrical holes that pass through said dome, said dome having a structure that is symmetrical around an axis of extension thereof, said holes being provided on the dome at radial distances from said axis of extension that increase according to an inverse square progression, said holes having port centers thereof that face externally said dome, arranged on radial circumferences that are mutually spaced with respect to said axis of extension so as to divide into two rings of equal area annular bands having equal surface area, into which a plan projection of said dome is divided.