Patent ID: 6379127
Filing Date: 2002-04-30
Classification: F04D

Abstract:
A submersible motor and pump assembly comprisinga motor and motor housing, said motor having an output shaft, a pump and pump housing, said pump housing connected to said motor housing, said pump being driven by said output shaft, a removable shaft sleeve mounted on said shaft, an inboard shaft seal proximate said motor, the rotating components of said inboard shaft seal mounted on said sleeve, an outboard shaft seal proximate said pump, a seal chamber interspersed between said motor and said pump, said seal chamber comprising in part the chamber side faces of said inboard shaft seal and said outboard shaft seal, said seal chamber charged with a buffer fluid under pressure at least equal to the pressure external of said motor and pump assembly at working depth, said buffer fluid having dielectric properties, a seal chamber pressurization system and at least one pressure reservoir integral to said motor and pump assembly for maintaining a positive pressure gradient within said seal chamber across said shaft seals, a buffer fluid circulation impeller mounted on said sleeve within said seal chamber proximate said outboard shaft seal, said impeller having at least one internal passageway connecting a rotationally normally forward facing intake tube on the periphery of said impeller to a discharge port on the hub of said impeller proximate said outboard shaft seal, and a multiplicity of radially oriented stator flanges in said seal chamber outboard of said impeller, one edge of said flanges being closely adjacent the arc of rotation of said intake tube.