Pump

Claim 1

A PUMP, COMPRISING A PUMP HOUSING INCLUDING A BODY HAVING A LIQUID INLET AND A LIQUID OUTLET AND INCLUDING A BACK PLATE ENCLOSING AN OPEN END OF THE BODY, AN IMPELLER LOCATED WITHIN THE HOUSING AND HAVING A PLANAR BACK SURFACE FACING SAID BACK PLATE, SAID BACK SURFACE HAVING A THREADED RECESS THEREIN, A MOTOR HAVING A MOTOR DRIVE SHAFT EXTENDING WITHIN AN OPENING IN THE BACK PLATE WITH THE OUTER END OF THE SHAFT BEING THREADEDLY RECEIVED WITHIN SAID RECESS, SAID MOTOR SHAFT HAVING A RADIALLY EXTENDING SHOULDER DISPOSED IN BEARING ENGAGEMENT WITH SAID BACK SURFACE, SAID BACK PLATE HAVING AN INTERNAL RECESS BORDERING THE OPENING THEREIN, AND A STATIONARY SEALING ASSEMBLY LOCATED WITHIN THE RECESS IN THE BACK PLATE AND EXTENDING WITHIN THE HOUSING, SAID SEALING ASSEMBLY INCLUDING AN ANNULAR SEAL HAVING AN AXIALLY EXTENDING INNER SECTION SPACED FROM SAID SHAFT AND A CENTRAL SECTION EXTENDING OUTWARD FROM SAID AXIAL SECTION, SAID SEAL ALSO INCLUDING AN OUTER SEALING SECTION EXTENDING LONGITUDINALLY FROM THE OUTER END OF SAID CENTRAL SECTION IN THE OPPOSITE DIRECTION FROM SAID INNER SECTION, SAID OUTER SEALING SECTION DISPOSED AT A LOCATION SPACED RADIALLY OUTWARD OF SAID SHOULDER, SAID SEALING ASSEMBLY ALSO INCLUDING RESILIENT MEANS DISPOSED IN ENGAGEMENT WITH SAID CENTRAL SECTION FOR URGING SAID SEALING SECTION INTO ENGAGEMENT WITH THE BACK SURFACE OF THE IMPELLER.