Balanced rotary servovalve

A force balanced rotory valve comprising:

• a hollow cylindrical valve housing having a longitudinal axis and first and second opposite ends and defining a central radial inlet port therein and a central radial outlet port therein equal in area to each other and located in axial alignment and one hundred eighty degrees in angular displacement from each other, first end and second end radial inlet ports respectively located in said first and second ends of said valve housing in angular alignment with each other and with said central outlet port and longitudinally displaced equidistantly from said central outlet port, and first end and second end radial outlet ports respectively located in said first and second ends of said valve housing in angular alignment with each other and with said central inlet port and axially displaced equidistantly from said central inlet port, and each of said first and second end inlet and outlet ports has an area half that of each of said central ports, and
• a valve closure element of cylindrical configuration rotatably mounted within said valve housing and defining central, first end and second end transverse passages therethrough which are respectively longitudinally aligned with said central ports, said first end ports, and said second end ports, and said first end passageways and said second end passageways are each of a cross-sectional area one-half that of each of said central passageways, and said passageways extend in a transverse direction.

A rotory valve comprising:

• a hollow cylindrical valve housing having a longitudinal axis and first and second opposite ends and defining a central inlet port and a central outlet port equal in area to each other and longitudinally aligned and angularly displaced one hundred eighty degrees from each other, a first end inlet port and a first end outlet port equal in area to each other and each equal to half the area of each of said central ports and longitudinally aligned and angularly displaced one hundred eighty degrees from each other and located in said first end of said valve housing at a longitudinal offset distance from said central ports, a second end inlet port and a second end outlet port equal in area to each other and each equal to half the area of each of said central ports and longitudinally aligned and angularly displaced one hundred eighty degrees from each other and located in said second end of said valve housing at said same longitudinal offset distance from said central ports, and
• a valve core of cylindrical configuration rotatably mounted within said valve housing and having central, first end, and second end passageways defined therethrough which are respectively longitudinally aligned with said central, first end and second end ports, and said first end and second end passageways each have a cross-sectional area half that of said central passageway, and said passageways are oriented so as to provide concurrent fluid flow through said passageways through all of said ports when said valve core is rotated to an open position within said valve housing and so as to concurrently block all of said passageways when said valve core is rotated to a closed position within said valve housing.

A rotory servovalve comprising:

• a valve housing of a cylindrical shape and having a valve cavity of circular cross section defined therewithin and defining at least two rectangular inlet ports to said valve cavity, and at least one of said fluid inlet ports is angularly offset one hundred eighty degrees from at least one other of said fluid inlet ports, at least two rectangular outlet ports from said valve cavity and at least one of said fluid outlet ports is angularly offset one hundred eighty degrees from at least one other of said fluid outlet ports, and at least two first rectangular fluid control ports in communication with said valve cavity and at least one of said first fluid control ports is angularly offset one hundred eighty degrees from at least one other of said first fluid control ports, and at least two second rectangular fluid control ports in communication with said valve cavity and at least one of said second control ports is angularly offset one hundred eighty degrees from one other of said second fluid control ports and said first and second fluid control ports are all angularly offset equidistantly from all of said inlet and outlet ports,
• a bidirectional valve closure element having a gate portion with at least two pairs of two mutually parallel, flow directing faces of rectangular shape, and said pairs of flow directing faces are longitudinally offset from each other and are longitudinally aligned with said ports and said flow directing faces in each pair are longitudinally aligned with each other and laterally spaced from each other, whereby pairs of longitudinally offset parallel flow paths are established through said valve housing and through said gate portion of said valve closure element, and said valve closure element is located within said valve cavity and is coaxially aligned and rotatable therewithin to, in the alternative:
• (1) permit concurrent fluid flow therethrough in opposite directions within each pair of mutually parallel flow paths, and (2) concurrently block all of said inlet ports and all of said outlet ports.