US 12,494,687 B2
Rotor assembly with a composite sleeve that is optimized for press-fit installation
Anthony Michael Coppola, Rochester Hills, MI (US); Derek Frei Lahr, Ann Arbor, MI (US); Alireza Fatemi, Canton, MI (US); Alan G. Holmes, Clarkston, MI (US); Michael B. Viola, Macomb Township, MI (US); and Bradley Allen Newcomb, Troy, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Oct. 31, 2022, as Appl. No. 17/977,068.
Prior Publication US 2024/0146131 A1, May 2, 2024
Int. Cl. H02K 1/28 (2006.01); H02K 1/04 (2006.01)
CPC H02K 1/28 (2013.01) [H02K 1/04 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A rotor for an electric machine, comprising:
a magnetic core configured for arrangement on a shaft;
an end ring arranged on opposite axial ends of the magnetic core, the end ring having an axial thickness; and
a composite sleeve comprising an annular body including an inner surface and an outer surface, and a polymer matrix encapsulating circumferentially oriented fibers,
wherein the composite sleeve includes a first tapered portion on the inner surface arranged adjacent to an axial end thereof and configured to facilitate press-fitting of the composite sleeve onto the rotor,
wherein the end ring includes a second tapered portion configured to bias the first tapered portion to facilitate press-fitting of the composite sleeve onto the rotor,
wherein the second tapered portion extends in an axial direction from a flat portion arranged parallel to an axial direction,
wherein the second tapered portion of the end ring extends 75% to 95% of the axial thickness of the end ring and terminates at the flat portion, and
wherein the flat portion has a diameter greater than or equal to a diameter of the magnetic core.