Floating controlled gap seal

Claim 1

A CIRCUMFERENTIAL SHAFT SEAL WHICH COMPRISES AN ANNULAR CASING HAVING OPPOSED SIDE WALLS WITH A SHAFT RECEIVING APERTURE, A MOUNTING RING LOOSELY FITTED IN SAID CASING AND ADAPTED TO MOVE AXIALLY AND RADIALLY IN THE CASING, KEY AND SLOT MEANS HOLDING THE MOUNTING RING AGAINST ROTATION IN THE CASING WITHOUT IMPEDING RADIAL AND AXIAL MOVEMENT THEREOF, A FACE RING CARRIED BY SAID MOUNTING RING AND EXTENDING RADIALLY INWARD THEREFROM INTO CLOSE RUNNING CLEARANCE RELATION WITH A SHAFT TO BE SEALED, SAID FACE RING HAVING A LATERALLY PROJECTED NOSE PORTION FOR ENGAGING A SIDE WALL OF THE CASING AND AN OPPOSITE RADIAL SIDE FACE, A SPLIT CARBON SEAL RING BOTTOMED ON SAID RADIAL FACE OF THE FACE RING AND SURROUNDED BY SAID MOUNTING RING, A WAVE SPRING BETWEEN THE MOUNTING RING AND SEAL RING EFFECTIVE TO CONTRACT THE SEAL RING ON A SHAFT TO BE SEALED, KEY AND SLOT MEANS ON THE MOUNTING RING AND SEAL RING HOLDING THE SEAL RING AGAINST ROTATION IN THE MOUNTING RING, AND AN AXIAL LOADING SPRING BETWEEN THE SEAL RING AND ADJACENT SIDE WALL OF THE CASING FOR URGING THE SEAL RING INTO SEALING ENGAGEMENT WITH THE RADIAL FACE OF THE FACE RING WHILE SIMULTANEOUSLY URGING THE NOSE OF THE FACE RING AGAINST THE OPPOSITE SIDE WALL OF THE CASING.