Positive isolation disconnect

A positive isolation quick-disconnect comprising:

• (a) A pair of axially separable valve housing members having through-bores communicating when said housings are coupled at an interface to form a passage therethrough, wherein the coupled ends of said housings are radially outwardly flanged and spaced away from said interface, and wherein one of said housings is provided with a pair of radially outwardly extending coaxial, fixed stub shafts;
• (b) a poppet valve axially slidable within each of said housings and disposed in coaxial, end-to-end relationship with their abuting ends capable of forming a fluid-tight interface;
• (c) a valve seat in each of said housings for sealingly engaging said valves at said interface;
• (d) an operating stem engaging each of said valves for controlling the positions of said valves, said stems extending through said housings for external manipulation of said valves through their open and closed positions;
• (e) clamping means for selectively connecting and disconnecting said housings, said clamping means comprising (1) a pair of cross-linked pivot legs disposed on opposite sides of said one housing, each said pivot leg having a cylindrical boss with an eccentric opening therethrough for receiving one of said housing stub shafts extending radially therethrough, said eccentric openings being coaxial with one another and said pivot legs being cross linked for common rotation, and (2) a generally U-shaped clamping yoke having a pair of generally parallel arms each with one free end and a crossarm joining the other ends of said parallel arms, said free ends being provided with a pair of opposed, transverse coaxial cylindrical openings for receiving said cylindrical bosses of said pivot legs in rotatable relationship, said parallel arms being generally disposed to straddle said one housing and parallel to the axis thereof, and said crossarm of said yoke being disposed to matingly engage said end flanges of said other housing, said clamping means having a relaxed position in one rotary position of said pivot legs in which no pulling force is exerted through said yoke and said flanges are separated by a gap, and an engaged position in a second rotary position of said pivot legs in which a pulling force is exerted through said clamping yoke to eliminate said gap and thereby clamp said flanges together in sealing, fluid-flow relationship;
• and
• (f) interlock means between said valve operating stems and said clamping means to permit release of the clamping means only when both of said valves are in the closed position.