Patent ID: 6447269
Filing Date: 2002-09-10
Classification: F04D,F05D

Abstract:
In a pump-motor for delivering potable water in a demand system comprising:a housing; a volute body secured to said housing including an inlet port and a discharge tube; an impeller in said volute body and a first chamber adjacent said impeller; an electric motor in said housing including a stator, a hollow rotor shaft, a rotor secured to said hollow rotor shaft, and first and second bearings supporting said hollow rotor shaft; a sleeve in said housing supporting said second bearing, a piston in said sleeve and resilient means urging said piston toward said second bearing, a water-impervious substantially non-magnetic sleeve positioned coaxially within said stator; a water-impervious substantially non-magnetic sleeve positioned on the outside of said rotor; said rotor, said sleeves defining a cylindrical path across said rotor; and a lubrication and cooling circuit through said pump-motor including fluid pathways between said hollow rotor shaft and said bearings, through said cylindrical path and through the interior of said hollow rotor shaft to said volute body.