Rotary actuated directional control valve

Claim 1

A rotary actuated directional control valve comprising: a housing having formed therethrough a central through bore and a first set and a second set of fluid passages the axis of each of which set is perpendicular to the axis of said through bore and intersects said through bore and each of which consists of a first and a second bore; a cylindrical valve spool member rotatably mounted in said through bore and having two annular passages formed in the exterior surface of said spool member on the opposite sides thereof, said annular passages being separated from each other and individually registering axially with said sets of fluid passages and each having a sufficient arc length to connect one of said diametrically opposed bores of said first set of fluid passages to a bore of said second set of fluid passages; said first bore of said first set of fluid passages and said first bore of said second set of fluid passages intersect said through bore at a first axial position, and said second bore of said first set of fluid passages and said second bore of said second set of fluid passages intersect said through bore at a second axial position, said annular passages extend at an angle inclined to the axis of said spool member and for a length less than circumferentially around said spool member such that fluid communication is provided between bores at said first axial position and bores at said second axial position and in which a line perpendicular to the axis of said spool meMber through the center of one said annular passages will intersect the center of said other annular passage.