Sealing and cooling device for a pump shaft

Claim 1

A SEALING AND COOLIONG DEVICE FOR A SHAFT OF A ROTARY PUMP WHICH IS ADAPTED FOR PUMPING FLUID OF RELATIVELY HIGH TEMPERATURE, SAID DEVICE COMPRISING: A CASING HAVING AN IMPELLER CHAMBER AND A SEAL CHAMBER IN COMMUNICATION WITH EACH OTHER THROUGH AN AXIAL PASSAGE INTO SAID IMPELLER CHAMBER; BERS; A ROTATABLE SHAFT EXTENDING THROUGH SAID SEAL CHAMBER AND HAVING AN END EXTENDING WITH CLEARANCE THROUGH SAID AXIAL PASSAGE INTO SAID IMPELLER CHAMBER; A PRIMARY IMPELLER CARRIED BY SAID SHAFT WITHIN SAID IMPELLER CHAMBER FOR ROTATION THEREIN; A PLURALITY OF AXIALLY SPACED GROUPS OF ANNULAR SEALS SURROUNDING SAID SHAFT IN SPACED RELATIONSHIP THERETO WITHIN SAID SEAL CHAMBER FOR PERMITTING A RESTRICTED FLOW OF FLUID ALONG SAID SHAFT INTERMEDIATE SAID ANNULAR SEALS AND SAID SHAFT; MEANS FOR INTRODUCING COOLING FLUID INTO SAID SEAL CHAMBER INTERMEDIATE SAID GROUPS OF ANNULAR SEALS SUCH THAT PORTIONS OF SAID COOLING FLUID FLOW CONTINUOUSLY BETWEEN EACH OF SAID GROUPS OF ANNULAR SEALS AND SAID SHAFT TOWARDS THE OPPOSING ENDS OF SAID SHAFT; AND AN AUXILIARY IMPELLER UPON SAID SHAFT WITHIN SAID SEAL CHAMBER FOR ROTATION THEREIN FOR DIRECTING THE PORTION OF SAID COOLING FLUID THAT FLOWS TOWARDS SAID IMPELLER CHAMBER THROUGH SAID AXIAL PASSAGE IN SAID WALL INTO SAID IMPELLER CHAMBER.