Fluid flow control manifolds and devices

Claim 1

A three-way valve comprising: a valve body having first, second and third ports; a first valve seat having an opening therethrough in communication with said first port; a second valve seat having an opening therethrough in communication with said second port; first and second valves guided in said body in a manner to be moved into and out of engagement with said first and second valve seats, respectively, to close and to open said first and second valve seat openings, respectively, said valves having a common substantially symmetrical axis extending in the directions of movement thereof, said body having first and second chambers outside said openings surrounding and spaced from said first and second valves, respectively, said chambers being in communication with each other and with said third port; means actuable to operate said first valve, said body having a plurality of holes therethrough parallel to and substantially symmetrical about the said axis of said valves; and a rod for each of said holes mounted between said valves and slidable through said holes, said rods causing said valves to move in tandem by opening said second valve when said first valve is closed and vice versa, said rods engaging both of said valves at positions spaced a radial distance from the axis of said valves greater than the radial distance each corresponding seat is spaced from said axis; said holes and rods being cylindrical, there being two rods and two holes, said first and second ports having parallel bore axes lying in a first plane through the axis of said valves, said holes having axes lying in a second plane disposed at an angle of approximately 45* relative to said first plane and passing through the axis of said valves, said body having two cylindrical passageways disposed on opposite sides of the axis of said valves equidistant from the axis of said valves, said passageways having axes lying in a third plane normal to said second plane and passing through the axis of said valves, each of said passageways being in communication with both of said chambers; said fiRst valve moving toward said second chamber when it moves toward said first seat, said first valve including a member, a valve element movably guided in said member, a first spring mounted in said member in a position to bias said first valve element toward said first seat, said member including stop means to prevent movement of said valve element toward said first seat beyond a predetermined limit, a second spring mounted in said body tending to bias said second valve closed, said second spring normally holding said second valve closed and said first valve open, and operator means actuable to close said first valve against the force of said second spring, said first spring allowing said member to overtravel said first seat when said operator means is actuated, said rods being fixed to said second valve and abutting said first valve.