Packed screw threaded gland type tube coupling for thin walled tubing

Claim 1

IN COMBINATION, A TUBE OF UNIFORM THICKNESS, A BEAD ON THE TUBE, A BODY MEMBER HAVING A BORE THEREIN, A COUPLING MEMBER, MEANS ENGAGING THE COUPLING MEMBER WITH THE BODY MEMBER, AND A SEALING RING POSITIONED OVER AN END PORTION OF THE TUBE, THE COUPLING MEMBER URGING THE BEAD AGAINST THE BODY MEMBER, THE IMPROVEMENT WHEREIN SAID END PORTION OF THE TUBE IS CYLINDRICAL AND IS OF LESSER DIAMETER THAN THE DIAMETER OF THE TUBE ON THE OTHER SIDE OF THE BEAD, THE BEAD THEREBY HAVING A FIRST RADIAL WALL AT ONE SIDE THEREOF ADJACENT SAID END PORTION OF ONE AREA AND A SECOND RADIAL WALL AT THE OTHER SIDE OF SAID BEAD OF LESSER AREA THAN THAT OF SAID FIRST RADIAL WALL, SAID BEAD HAVING ITS INNER WALLS IN CONTACT, SAID BEAD BEING OF GENERALLY SEM-CIRCULAR CONFIGURATION, SAID BODY MEMBER HAVING AN ENLARGED PORTION OF THE BORE RECEIVING THE END PORTION OF SAID TUBE, SAID BODY MEMBER HAVING A FURTHER ENLARGED PORTION OF ITS BORE OUTWARDLY OF SAID FIRST ENLARGED PORTION FORMING A CYLINDRICAL RECESS FOR THE SEALING RING FORMED BY TWO INTERSECTING WALLS, ONE OF SAID INTERSECTING WALLS BEING SUBSTANTIALLY RADIALLY DISPOSED AND THE OTHER OF SAID INTERSECTING WALLS BEING SUBSTANTIALLY AXIALLY DISPOSED, SAID BODY MEMBER HAVING A STILL FURTHER ENLARGED PORTION OF ITS BORE EXTENDING OUTWARDLY AT AN OBTUSE ANGLE FROM SAID AXIALLY DISPOSED WALL AND PROVIDING A CONTACT SURFACE FOR SAID BEAD ABOVE SAID AXIALLY DISPOSED WALL, SAID CONTACT SURFACE HOLDING THE TUBE IN FIRM ENGAGEMENT AND THEREBY PREVENTING ROTATION OF THE TUBE AND PROVIDING A METAL TO METAL SEAL, THE SEALING RING ENGAGED BETWEEN THE END PORTION OF THE TUBE AND THE SEALING RECESS AXIAL WALL THEREBY PROVIDING AN O RING SEAL, THE DIAMETER OF THE OPENING IN THE COUPLING MEMBER BEING SUCH AS TO PROVIDE A CLOSE FIT WITH THE SURFACE OF THE TUBE OPPOSITE THE END PORTION OF LESSER DIAMETER, SAID COUPLING MEMBER HAVING A TUBE ENGAGING PORTION OF AN AXIAL LENGTH AT LEAST FOUR TIMES THE LENGTH OF SAID SECOND RADIAL WALL OF LESSER AREA AGAINST WHICH IT ABUTS.