US 5,188,337 A · Control valve with pressure equalization

Abstract

A control valve for fluid media has an adjusting piston which is displaceable by a drive and whose face end can be seated against a valve seat. The adjusting piston and the drive are disposed in a valve housing which is completely filled with fluid. The adjusting piston is formed by a hollow body through which fluid can flow on both sides in the direction of its axis, and the hollow body surrounds a cavity. The cavity is sealed by a first sealing member extending transversely of its axis against the valve housing, and by a second sealing member which extends against a dividing wall which is contained in the cavity and is displaceable in a direction of the axis. The valve housing is filled on one side of the first and second sealing member facing away from the valve seat with an incompressible hydraulic protective fluid.

Claims13

Dependent claims

A flow control valve for a fluid medium comprising

a housing having a valve seat,
a hollow piston defining a cavity therein, said piston being movable in said housing along an axis toward and away from said valve seat,
a dividing wall transverse to said axis in said cavity, said dividing wall being movable along said axis relative to said piston,
first sealing means between said piston and said housing,
second sealing means between said piston and said dividing wall,
a closed chamber formed by said housing, said piston, said dividing wall, and said first and second sealing means opposite from said valve seat, said closed chamber having an incompressible hydraulic fluid therein, and
adjusting means for controlling the position of said piston relative to said valve seat.

4 more elements

Dependencies are inferred from the claim text.

Control valve with pressure equalization

Life of this patent

Control valve with pressure equalization

Life of this patent

Abstract

Claims13