Hydraulically controllable globe valve

摘要

A hydraulically controllable globe valve having a stem piston to which pressure can be applied by a spring connected to a pressure source, with the stem piston being able to move from a first end position in the direction of a second end position. Pressure control means are provided which maintain a constant pressure of the hydraulic spring means on the stem piston while the latter moves from the first end position in the direction of the second end position by connecting the hydraulic spring means to a pressure source during a variable portion of the valve lift. The valve can be used, for example, as a gas exchange valve in a reciprocating engine.