SPOOL VALVE FOR FLUID CONTROL

摘要

A spool valve is provided with a stem portion (60f) that defines a fluid passageway (56f) formed by either (a) a single central support having a non-cylindrical curved surface shaped hydrodynamically, or (b) only a pair of sidewalls with, preferably, interior surfaces that are also shaped hydrodynamically. These stem passageways, which are designed to facilitate the flow of high-speed/high-pressure fluids controlled by the valve, are maintained in a predetermined orientation relative to the ports of the valve cylinders by a mechanism preferably including (a) a cam-following roller (66a) supported in a tang (62a) fixed to each spool and (b) a two-element cam that captures the roller (66a) within two of the parallel sides of a cam-track groove formed in the respective interior surfaces of each cam element.