Sealing means for rotary pump shafts and the like

Claim 1

A CENTRIFUGAL TURBINE PUMP COMPRISING A CASING HAVING A PAIR OF INTERNAL PUMPING CHAMBERS, A PUMP SHAFT MOUNTED FOR ROTATION WITHIN SAID CASING, TURBINE IMPELLER AND ROTATABLE PART FIXED FOR ROTATION WITH SAID SHAFT, SAID TURBINE IMPELLER BEING OPERABLE WITHIN ONE PUMPING CHANNEL, A CENTRIFUGAL IMPELLER FIXED ON THE END OF SAID SHAFT FOR ROTATION WITH SAID SHAFT AND OPERABLE WITHIN THE OTHER PUMPING CHAMBER, SAID TURBINE IMPELLER HAVING VANES AT ITS OUTER PERIPHERY OPERABLE WITHIN ONE OF SAID PUMPING CHAMBERS, LINERS DISPOSED WITHIN SAID CASING AND COOPERATING WITH OPPOSITE SIDES OF SAID TURBINE IMPELLER INWARDLY OF SAID VANES TO FORM SEALING SURFACES THEREWITH, A STATIONARY ANNULAR SEAL BUSHING SURRUNDING SAID SHAFT AND DISPOSED BETWEEN SAID CENTRIFUGAL AND TURBINE IMPELLERS, AND A RING CLOSELY FITTING SAID ROTATABLE PART OF THE PUMP AND FIXED FOR ROTATION WITH SAID SHAFT INCLUDING A PIN ROTATABLE WITH SAID SHAFT, SAID RING HAVING A LONGITUDINAL GROOVE ENGAGINS SAID PIN FOR AXIAL MOVEMENT, SAID CLOSE FITTING RING BEING DISPOSED BETWEEN SAID TURBINE IMPELLER AND SAID ANNULAR SEAL BUSHING AND MOVABLE LONGITUDINALLY WITH RESPECT TO SAID SHAFT, SAID CLOSE FITTING RING AT THE END TOWARD SAID TURBINE IMPELLER BEING EXPOSED TO PRESSURE FROM THE TURBINE IMPELLER REACHING THE END OF SAID CLOSE FITTING RING ALONG THE SEALING SURFACES BETWEEN THE TURBINE IMPELLER AND THE LINER WHEREBY SUCH PRESSURE FORCES SAID CLOSE FITTING RING LONGITUDINALLY AGAINST SAID ANNULAR SEAL BUSHING TO SEAL OFF PRESSURE FROM SAID TURBINE IMPELLER TO THE CENTRIFUGAL STAGE OF THE PUMP.