US 12,355,335 B2
Rotor for an electric motor
Mario Mohler, Rosengarten (DE); and Christoph Steinmetz, Ludwigsburg (DE)
Assigned to Mahle International GmbH, (DE)
Filed by MAHLE International GmbH, Stuttgart (DE)
Filed on Oct. 6, 2022, as Appl. No. 17/961,496.
Claims priority of application No. 102021211340.0 (DE), filed on Oct. 7, 2021.
Prior Publication US 2023/0112512 A1, Apr. 13, 2023
Int. Cl. H02K 9/19 (2006.01); H02K 7/00 (2006.01)
CPC H02K 9/19 (2013.01) [H02K 7/003 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A rotor for an electric motor, comprising:
a rotor shaft with a hollow space arranged in the rotor shaft at least in regions,
the hollow space is structured as a cooling channel and has an inner surface,
wherein at least one of (i) the inner surface of the hollow space comprises structures for an enlargement of a surface area, and (ii) in the hollow space at least one structural element is provided directly or indirectly connected to the inner surface of the rotor shaft for at least one of the enlargement of the surface area and/or for the mixing of coolant, and
wherein the at least one of (i) the structures for the enlargement of the surface area and (ii) the at least one structural element is structured and arranged around the inner surface to provide a mixing chamber in an interior region of the hollow space for mixing of coolant,
wherein the at least one structural element is provided and comprises a spring steel sheet contacting the inner surface of the hollow space, the spring steel sheet including flow guide elements arranged spaced apart from one another and extending only partially inwards to promote a swirl of coolant in the hollow space.