Swivel pipe joint and means for preventing freezing thereof

Claim 1

A SWIVEL PIPE JOINT FOR ROTATABLY INTERCONNECTING TWO AXIALLY ALIGNED CONDUITS FOR CARRYING LOW TEMPERATURE FLUIDS, COMPRISING A FEMALE COUPLING MEMBER HAVING AN ENLARGED HOUSING ADJACENT ONE END, AN OUTWARDLY FACING ABUTMENT SURFACE AT THE INNER END OF SAID HOUSING, A MALE COUPLING MEMBER PROJECTING INTO SAID HOUSING WITH ITS END SURFACE ADJACENT BUT SPACED FROM SAID ABUTMENT SURFACE TO FORM A RADIAL PASSAGE THAT INTERRUPTS THE SMOOTH OTHERWISE CONTINUOUS BORE SURFACES OF THE MALE AND FEMALE COUPLING MEMBERS, BEARING MEANS IN SAID HOUSING INTERCONNECTING SAID COUPLING MEMBERS FOR RELATIVE ROTATION, A SEALING RING INTERPOSED BETWEEN SAID COUPLING MEMBERS EXTERNALLY OF SAID BEARING MEANS FOR PREVENTING LEAKAGE OF FLUID BETWEEN SAID MEMBERS, A PLURALITY OF RADIAL PORTS IN SAID MALE COUPLING MEMBER ADJACENT THE OUTERMOST PORTION OF SAID BEARING MEANS PROVIDING COMMUNICATION BETWEEN THE INTERIOR OF SAID MALE COUPLING MEMBER AND SAID SEALING RING IN THE INTERIOR OF SAID HOUSING TO BIAS SAID RING INTO SEALING ENGAGEMENT WITH SAID MALE COUPLING MEMBER, MEANS DEFINING AXIAL PASSAGEWAYS IN SAID HOUSING PROVIDING FLUID COMMUNICATION BETWEEN SAID RADIAL PORTS AND THE RADIAL PASSAGE BETWEEN THE END OF SAID MALE COUPLING MEMBER AND SAID ABUTMENT SURFACE, WHEREBY TURBULENCE IN THE VICINITY OF THE END OF SAID MALE COUPLING MEMBER CAUSES A PRESSURE DROP ADJACENT SAID RADIAL PASSAGE THUS ESTABLISHING FLUID FLOW FROM THE BORES THROUGH SAID RADIAL PORTS, THROUGH SAID AXIAL PASSAGEWAYS IN SAID HOUSING, AND BACK TO THE BORES VIA SAID RADIAL PASSAGE TO PREVENT CONDENSATION WITHIN SAID HOUSING.