US Patent 9581158 Submersible electric pump having a shaft with spaced apart shoulders

A submersible electric pump includes a housing adapted to be submerged within a fluid to be pumped having apertures extending therethrough. An electric motor stator is positioned within the housing in communication with the apertures and is adapted to be in contact with the fluid. Inner and outer pump rotors are positioned within the housing in meshed engagement with one another to pump fluid when rotated. A plurality of permanent magnets are fixed for rotation with the outer rotor.