Rotor Assembly Manufacturing Technique

A method of fabricating a rotor assembly for an electric motor, comprising:

• assembling a lamination stack, wherein said lamination stack is comprised of a plurality of lamination discs, wherein each of said lamination discs is comprised of a plurality of slots, said plurality of slots of said plurality of lamination discs co-aligned within said lamination stack, and wherein each of said lamination discs is further comprised of a central bore;
• inserting a plurality of conductive rotor bars into said plurality of slots corresponding to said lamination stack, wherein a first end region of each of said plurality of conductive rotor bars extends beyond a first end surface of said lamination stack, and wherein a second end region of each of said plurality of conductive rotor bars extends beyond a second end surface of said lamination stack, and wherein said first end region and said second end region of each of said plurality of conductive rotor bars is tapered;
• locating a rotor shaft within said central bore of said lamination stack;
• mounting a first end cap onto said rotor shaft and adjacent to said first end surface of said lamination stack, said first end cap comprising a first plurality of receptacles corresponding to said plurality of conductive rotor bars;
• inserting said first end region of each conductive rotor bar of said plurality of conductive rotor bars into a corresponding receptacle of said first plurality of receptacles, wherein each receptacle of said first plurality of receptacles is mechanically and electrically coupled to said first end region of each corresponding conductive rotor bar of said plurality of conductive rotor bars;
• mounting a second end cap onto said rotor shaft and adjacent to said second end surface of said lamination stack, said second end cap comprising a second plurality of receptacles corresponding to said plurality of conductive rotor bars;
• inserting said second end region of each conductive rotor bar of said plurality of conductive rotor bars into a corresponding receptacle of said second plurality of receptacles, wherein each receptacle of said second plurality of receptacles is mechanically and electrically coupled to said second end region of each corresponding conductive rotor bar of said plurality of conductive rotor bars;
• mounting a first locking member onto said rotor shaft and adjacent to said first end cap, wherein said first locking member applies a first axial compressive force on said first end cap to maintain said first end region of each conductive rotor bar of said plurality of conductive rotor bars within each corresponding receptacle of said first plurality of receptacles;
• and
• mounting a second locking member onto said rotor shaft and adjacent to said second end cap, wherein said second locking member applies a second axial compressive force on said second end cap to maintain said second end region of each conductive rotor bar of said plurality of conductive rotor bars within each corresponding receptacle of said second plurality of receptacles.