Rotatable flange adjustable pipe coupling

Claim 1

A FLANGE-TYPE COUPLING FOR JOINING A PAIR OF ALIGNED UNTHREADED PIPE ENDS COMPRISING: A PAIR OF IDENTICAL ANNULAR INSERT ELEMENTS FOR OPPOSING ALIGNMENT WITH EACH OTHER, ONE OF WHICH IS INSERTED BY A SLIDE FIT OVER EACH PIPE END, EACH INSERT ELEMENT HAVING ITS AXIALLY EXTENDING OUTER SURFACE FORMED AS A TRUNCATED CONE WITH THE OUTER CONICAL TAPER THEREOF INCREASING TOWARD THE REAR END WHICH LIES ADJACENT THE OUTER EDGE OF EACH PIPE END, THE SLOPE OF SAID TAPERED OUTER SURFACE OF EACH OF SAID INSERT ELEMENTS BEING FROM 1 TO 5 DEGREES; ANNULAR GASKET SEAL MEANS DISPOSED BETWEEN THE OPPOSING SURFACES OF SAID INSERT ELEMENTS; A PAIR OF IDENTICAL ANNULAR FLANGE RING MEMBERS EACH OF WHICH IS TAPERED AT ITS INNER BORE TO FIT OVER A CORRESPONDING ONE OF SAID INSERT ELEMENTS; A PLURALITY OF FLANGE BOLTS TO DRAW SAID INSERT ELEMENTS AND SEAL MEANS TOGETHER IN A UNITARY JOINT IN ASSEMBLED PAIRED RELATIONSHIP; EACH OF SAID INSERT ELEMENTS HAVING SPACED CONCENTRICALLY DISPOSED GROOVES AND LANDS ON THE INNER BORE, SAID GROOVES AND LANDS BEING EQUALLY SPACED AND EXTENDING FROM ONE AXIAL END OF SAID INNER BORE TO THE OTHER AND FORMING RIGHT ANGLE SERRATIONS, THE UNTHREADED PIPE END BEING INSERTED THEREIN FLUSH WITH THE AXIALLY FORWARD END FACES OF SAID INSERTS AND BEING RADIALLY OUTWARDLY PRESSED INTO SAID GROOVES AND RETAINED THEREIN BY SAID LANDS; EACH OF SAID ANNULAR FLANGE MEMBERS HAVING THE MAXIMUM DIAMETER OF ITS INNER WALLS LESS THAN THE MAXIMUM OUTER DIAMETER OF SAID INSERTS, THEREBY FRICTIONALLY LOCKING THE INSERTS IN SAID INNER WALLS; THE EXTERNAL FACE OF EACH OF SAID INSERTS BEING PROVIDED WITH A PLURALITY OF CONCETRIC GROOVES FOR GRASPING THE GASKET SEAL MEANS AND FOR PREVENTING LEAKAGE OF FLUID ACROSS SAID GASKET SEAL MEANS; AND SAID INSERTS BEING FURTHER PROVIDED AT THEIR AXIALLY FORWARD ENDS WITH A RADIALLY OUTWARDLY EXTENDING SHOULDER FOR PREVENTING THE INSERT FROM BEING PULLED IN AN OUTWARD DIRECTION PAST SAID SHOULDER THROUGH SAID FLANGE BORES, THE AXIALLY FORWARD END FACE OF SAID SHOULDER BEING IN THE SAME PLANE AS THE AXIALLY FORWARD END FACE OF SAID INSERT AND NORMAL TO THE AXIS OF SAID INSERT, SAID GROOVES FORMING A SAW TOOTH SURFACE EXTENDING FROM THE RADIALLY OUTER PORTION OF SAID FLANGES TO THE WALL OF THE BORE IN SAID INSERTS.