Tube coupling

Claim 1

A TUBE COUPLING COMPRISING TWO TUBES ARRANGED IN END-TO-END ABUTTING RELATIONSHIP, A SLEEVE SECURED TO EACH OF SAID TUBES ADJACENT THEIR ENDS, ONE OF SAID SLEEVES HAVING AN ENLARGED ANNULAR PORTION PROVIDED WITH A THREESIDED INWARDLY OPENING ANNULAR GROOVE AND HAVING AT THE OUTER AND INNER SIDES RESPECTIVELY OF SAID ANNULAR GROOVE OUTWARDLY FLARING ANNULAR PORTIONS, THE OTHER OF SAID SLEEVES HAVING AN OUTER CYLINDRICAL SURFACE EXTENDING INTO SAID ENLARGED ANNULAR PORTION, SAID OTHER SLEEVE HAVING A SEGMENTAL CIRCUMFERENTIALLY EXTENDING INCLINED FLANGE DISPOSED SUBSTANTIALLY PARALLEL TO ONE SIDE OF SAID THREE-SIDED ANNULAR GROOVE, SAID INCLINED FLANGE AND SAID ONE SIDE OF SAID THREE-SIDED ANNULAR GROOVE HAVING AT LEAST PORTIONS THEREOF IN SPACED OPPOSED RELATION, AND A COMBINED SEALING AND RETAINING RING HAVING AN ELASTOMERIC EXTERIOR SURFACE AND A REINFORCING MEANS IMBEDEDED THEREIN, SAID RING HAVING A HEXAGONAL RADIAL CROSS SECTION AND DISPOSED WITHIN AND HAVING SEALING ENGAGEMENT WITH THE THREE SIDES OF SAID THREE-SIDED ANNULAR GROOVE AND HAVING SEALING ENGAGEMENT WITH SAID OUTER CYLINDRICAL SURFACE AND WITH THE OUTER SIDE OF SAID FLANGE, THE OUTWARDLY FLARING ANNULAR PORTION UPON THE OUTER SIDE OF SAID ANNULAR GROOVE BEING OPERABLE TO FACILITATE INSERTION OF SAID RING INTO ENGAGEMENT WITH SAID ANNULAR GROOVE AND OPERABLE TO FACILITATE INSERTION OF SAID SEGMENTAL FLANGE INTO ENGAGEMENT WITH SAID RING, THE OUTWARDLY FLARING ANNULAR PORTION UPON THE INNER SIDE OF SAID ANNULAR GROOVE BEING OPERABLE TO LIMIT INSERTION OF SAID SEGMENTAL FLANGE RELATIVE TO SAID RING.