Electric machine having a rotor with retaining sleeve

An electric machine, comprising:

• a stator;
• and
• a rotor, the rotor comprising:
• a rotor hub with a cylindrical outer surface;
• a plurality of non-magnetic spacers on and contacting the cylindrical outer surface of the rotor hub;
• a plurality of permanent magnets arranged on the cylindrical outer surface between the spacers, the plurality of permanent magnets defining at least two magnetic poles of the rotor;
• a metallic shield surrounding an outward facing surface of the permanent magnets and spacers;
• and
• a retaining sleeve surrounding the rotor.

A rotor comprising:

• a central hub with a cylindrical outer surface;
• a plurality of elongate spacers affixed to the cylindrical outer surface of the central hub, the spacers circumferentially spaced apart from each other and extending axially along the outer surface of the central hub, where the spacers are non-magnetic and metal;
• a plurality of permanent magnets on the outer surface between the spacers, the plurality of permanent magnets defining at least two magnetic poles of the rotor;
• a metallic shield surrounding an outward facing surface of the permanent magnets and spacers;
• and
• a retaining sleeve surrounding an outward facing surface of the rotor, the retaining sleeve configured to retain the magnets to the central hub during operation of the rotor.