Controlled leakage face type seals

Claim 1

A FLUID SEAL ASSEMBLY COMPRISING A ROTATABLE SHAFT HAVING A FLAT RADIALLY EXTENDING SURFACE THEREON, HOUSING MEANS RECEIVING SAID SHAFT AND HAVING WALLS THEREON DEFINING A PRESSURE CHAMBER THEREIN, A SEAL RING HAVING A PAIR OF OPPOSED GENERALLY RADIAL SURFACES THEREON, SAID RING RECEIVING SAID SHAFT IN THE OPENING THEREOF AND MOUNTED IN SAID HOUSING MEANS IN AXIAL FLOATING RELATIONSHIP WITH SAID RADIAL SHAFT SURFACE, ONE OF SAID RADIAL RING SURFACES BEING EXPOSED DURING OPERATION OF SAID ASSEMBLY TO SAID PRESSURE CHAMBER, THE OTHER OF SAID RADIAL RING SURFACES CONFRONTING SAID RADIAL SHAFT SURFACE AND BEING SPACED THEREFROM WHEN SAID CHAMBER IS PRESSURIZED TO FORM A SEAL GAP THEREBETWEEN, SAID OTHER RING SURFACE HAVING ONE EXTREMITY THEREOF EXPOSED TO SAID PRESSURE CHAMBER AND HAVING THE OTHEE EXTREMITY THEREOF EXPOSED TO A RELATIVELY LOW PRESSURE REGION IN SAID HOUSING MEANS, SAID OTHER RING SURFACE HAVING A TAPERED PORTION INTERMEDIATE SAID EXTREMITIES AND EXTENDING TO SAID ONE EXTREMITY THEREOF, SAID PORTION BEING TAPERED TO GRADUALLY INCREASE THE THICKNESS OF SAID SEAL GAP TO A MAXIMUM THICKNESS ADJACENT SAID ONE EXTREMITY OF SAID RING AND THE REMAINDER OF SAID OTHER SEAL RING SURFACE BEING FLAT AND EXTENDING PARALLEL TO SAID SHAFT RADIAL SURFACE, SEALING MEANS DISPOSED BETWEEN SAID SEAL RING AND AN ADJACENT STATIONARY WALL PORTION OF SAID CHAMBER AT A POSITION ON SAID SEAL RING INTERMEDIATE SAID ONE RADIAL RING SURFACE AND SAID OTHER RADIAL RING SURFACE, AND SAID SEALING MEANS, SAID SEAL RING AND SAID HOUSING MEANS WALLS BEING RELATIVELY POSITIONED TO PREVENT FLUID FLOW FROM SAID PRESSURE CHAMBER TO SAID LOW PRESSURE REGION EXCEPT ALONG SAID SEAL GAP.