| 摘要 |
An insert assembly is mounted in a valve housing defining one incoming and two outgoing flow paths to further define the cross-sectional area of one outgoing flow path between its periphery and the inner surface of the housing. The insert assembly is made up of a hollow cylinder, a first and hollow piston arranged in the cylinder for movement with respect thereto, a second piston arranged in the hollow piston for movement with respect thereto, a third and blocking piston rigidly connected to the hollow piston for movement therewith for varying the cross-sectional area of the outgoing flow path further defined by the insert assembly, a slide valve arranged to selectively block the other of the outgoing flow paths, and a piston rod passing through the blocking piston for movement relative thereto and rigidly connecting the second piston to the valve slide so that the valve slide moves with the second piston. A control valve is operatively connected to the insert assembly to selectively move (1) the hollow piston and, thus, the blocking piston for opening and closing off the outgoing flow path associated with the blocking piston, and (2) the second piston and, thus, the valve slide for opening and closing off the other outgoing flow path. Means may be provided for closing off both flow paths simultaneously. |
