Frictional ring seals for rotating shafts

Claim 1

AN AXIALLY-BALANCED FRICTIONAL RING SEAL FOR CONTROLLING THE AXIAL FLOW OF LEAKAGE FLUID ALONG THE ROTARY SHAFT OF ROTARY PUMPS, TURBINES, COMPRESSORS AND THE LIKE, COMPRISING: (A) AN OUTER STATIONARY HOUSING PART PROVIDING A CYLINDRICAL BORE WALL HAVING HIGH AND LOW PRESSURE ENDS; (B) AN INNER ROTATABLE SHAFT PART OPERATIVELY MOUNTED FOR RELATIVE ROTATION WITHIN THE SAID BORE WALL AND INWARDLY SPACED THEREFROM; (C) A SERIES OF THREE AXIALLY-ABUTTING SHAFT-ENCIRCLING RINGS ARRANGED WITHIN SAID BORE WALL, (1) THE FIRST AND THIRD RINGS BEING MOUNTED ON ONE PART THROUGH ONE OF THEIR INNER AND OUTER PERIPHERIES WITH THEIR OTHER REMAINING OR FREE PERIPHERIES SEPARATE FROM THE OTHER PART, (2) THE SECOND RING BEING MOUNTED ON THE OTHER PART THROUGH THE OTHER OF ITS INNER AND OUTER PERIPHERIES WITH ITS REMAINING FREE PERIPHERY SEPARATE FROM SAID ONE PART, (3) SAID RINGS COOPERATING TO FORM (A) A FIRST FRICTIONAL SEAL EXTENDING RADIALLY BETWEEN THE ADJACENT FACES OF THE FIRST AND THE SECOND RINGS FROM AN ANNULAR INLET ADJACENT ONE OF ITS ENDS TO AN ANNULAR OUTLET ADJACENT THE OTHER OF ITS ENDS, AND (B) A SECOND FRICTIONAL SEAL EXTENDING RADIALLY BETWEEN THE ADJACENT FACES OF THE SECOND AND THIRD RINGS FROM AN ANNULAR INLET ADJACENT ITS MID-PORTION TO ANNULAR OUTLETS ADJACENT ITS OPPOSITE INNER AND OUTER ENDS; (D) MEANS FOR FEEDING LEAKAGE FLUID AT THE SAME PRESSURE TO THE INLETS OF THE FIRST AND SECOND FRICTIONAL SEALS; AND (E) PRESSURE EQUALIZING PASSAGEWAY MEANS INTERCONNECTING THE OUTLET OF THE FIRST FRICTIONAL SEAL WITH BOTH OUTLETS OF THE SECOND FRICTIONAL SEAL.