Rotor shaft hub and bearing for a high pressure fluid pump assembly

A pump assembly for pumping a fluid comprising:

• a pump having a driving rotor and a driven rotor that is coupled to and rotated by the driving rotor to cause the fluid to be pumped;
• a shaft coupled to the driving rotor, said shaft being rotated to cause the driving rotor of said pump to rotate and to correspondingly impart the rotation thereof to said driven rotor;
• a bearing having a shaft passage running longitudinally therethrough within which to receive said shaft in order to maintain said shaft in axial alignment with the driving rotor of said pump;
• a hub within which to receive and surround said bearing and thereby minimize wobbling of said shaft in response to axial and radial loads to which said shaft is exposed during the rotation thereof;
• and
• a front cover having a hub receiving pocket formed therein, said hub being received within said hub receiving pocket and said bearing being surrounded by said hub, such that said shaft extends through the shaft passage of said bearing to be axially aligned with and coupled to the driving rotor of said pump,
• wherein said hub includes a mounting flange to be connected to said front cover, said mounting flange having first an opposite faces and said hub further including a bearing pocket located at the first face of said mounting flange for the receipt therewithin of said bearing and a hub alignment boss located at the opposite face of said mounting flange to be received within said hub receiving pocket, said hub having a shaft pass-through running longitudinally therethrough for the receipt of said shaft, such that said shaft is coaxially aligned with each of the shaft passage of said bearing and the shaft pass-through of said hub so as to be aligned with and coupled to the driving rotor of said pump.