Coupling

Claim 1

IN A COUPLING FOR CONNECTING TWO CONFRONTING TUBE ENDS, THE COMBINATION OF: A PAIR OF RADIAL FLANGES ON EACH OF SAID TUBE ENDS SPACED APART TO FORM A CIRCUMFERENTAIL GROOVE ON THE TUBE END; AN ELASTOMER SEALING RING SEATED IN EACH OF SAID GROOVES; A CYLINDRICAL BODY TO BRIDGE THE TWO TUBE ENDS AND ENCLOSE ALL OF SAID FLANGES, THE UNRESTRAINED RADIAL DIMENSION OF EACH OF SAID SEALING RINGS BEING GREATER THAN THE RADIAL CLEARANCE BETWEEN THE COUPLING BODY AND THE BOTTOM OF THE GROOVE IN WHICH THE SEALING RING IS SEATED WHEREBY EACH SEALING RING IS RADIALLY COMPRESSED BY THE COUPLING BODY FOR EFFECTIVE SEALING CONTACT BOTH WITH THE COUPLING BODY AND WITH THE BOTTOM WALL OF THE GROOVE IN WHICH THE SEALING RING IS SEATED WITH CONSEQUENT AXIAL ELONGATION OF THE SEALING RING, EACH OF SAID GROOVES BEING OF AW WIDTH DIMENSIONED TO OPPOSE THE AXIAL ELONGATION OF THE SEALING RING WITH CONSEQUENT INCREASE IN THE RADIAL PRESSURE OF THE SEALING RING OUTWARDLY AGAISNT THE COUPLING BODY AND INWARDLY AGAINST THE CORRESPONDING TUBE END, THE INTERIOR OF ONE END OF SAID COUPLING BODY BEING FLARED TO FACILITATE SLIDING ADVANCE OF THE COUPLING BODY OVER THE CORRESPONDING SEALING RING WITH CONSEQUENT RADIAL COMPRESSION OF THE SEALING RING, SAID ONE END OF THE COUPLING BODY BEING FORMED WITH A FIRST SCREW THREAD; RADIALLY INWARDLY EXTENDING MEANS ON THE TWO ENDS RESPECTIVELY OF SAID COUPLING BODY IN ABUTMENT WITH THE REARMOST FLANGES OF THE TWO TUBE ENDS TO LIMIT SEPARATION MOVEMENT OF THE TWO TUBES, ONE OF SAID INWARDLY EXTENDING MEANS BEING AT THE FLARED END OF THE COUPLING BODY AND BEING A RING MEMBER FORMED WITH A SECOND SCREW THREAD FOR RELEASABLE ENGAGEMENT WITH SAID FIRST SCREW THREAD, SAID TWO SCREW THREADS BEING POSITIONED AND DIMENSIONED FOR SCREW ACTION OF THE RING MEMBER AGAINST THE REARMOST FLANGE OF THE CORRESPONDING TUBE END TO FORCE SAID FLARED PORTION OF THE COUPLING BODY OVER THE CORRESPONDING SEALING RING.