Patent ID: 8272393

Claim:
A valve for automatic switchover from a plurality of fluid pressure sources to a common outlet, including: a valve body including first and second inlet ports in fluid communication with first and second spool chambers, respectively, wherein each of said first and second inlet ports are adapted for fluid communication with respective fluid pressure sources, and each of said first and second spool chambers include an end chamber, and each of said first and second spool chambers include a primary chamber, a secondary chamber; first and second spools respectively in said first and second spool chambers and each including at least one sealing member carried thereon for selective sealing engagement with a portion of said first and second spool chambers, respectively, wherein each of said first and second spools are resiliently biased towards an open position, and fluid-biased towards a closed position; fluid passageways extending through said valve body receiving spool controlled fluid pressures and each terminating at the end chamber of said first and second spool chambers, wherein in an open position, each of said first and second spools are adapted to provide delivery of pressurized fluid from an associated one of the inlet ports to the end chamber of the opposite spool chamber, and further wherein in a closed position, each of said first and second spools are adapted via the at least one sealing member to inhibit delivery of pressurized fluid from an associated one of the inlet ports to the end chamber of the opposite spool chamber; and a manifold assembly including at least one manifold bore in fluid communication with each of the end chambers and the common outlet, said manifold assembly including first and second manifold spools moveable within said at least one manifold bore between open and closed positions for alternatively providing fluid communication between one of said end chambers and the common outlet while inhibiting fluid communication between the other of said end chambers and the common outlet, wherein the first and second manifold spools are movable in response to the fluid pressure provided from an associated one of the end chambers, and wherein at least one of said first and second manifold spools includes an indicator portion movable together with said at least one of said first and second manifold spools and adapted to selectively extend a distance out of the manifold assembly to be visible from outside of the manifold assembly, wherein an interior surface of each of said spool chambers includes a tapered geometry extending between said primary and secondary chambers providing an increased cross-sectional area generally about the first and second inlet ports to facilitate sealing engagement of the sealing member with said portion of the spool chamber.