US 12,395,049 B2
Method for producing a squirrel-cage rotor of an asynchronous machine
Klaus Büttner, Hollstadt (DE); Klaus Kirchner, Ostheim (DE); and Matthias Warmuth, Windshausen (DE)
Assigned to Innomotics GmbH, Nuremberg (DE)
Appl. No. 17/630,058
Filed by Innomotics GmbH, Nuremberg (DE)
PCT Filed Jul. 17, 2020, PCT No. PCT/EP2020/070267
§ 371(c)(1), (2) Date Jan. 25, 2022,
PCT Pub. No. WO2021/032379, PCT Pub. Date Feb. 25, 2021.
Claims priority of application No. 19192098 (EP), filed on Aug. 16, 2019.
Prior Publication US 2022/0320975 A1, Oct. 6, 2022
Int. Cl. H02K 15/023 (2025.01); H02K 17/20 (2006.01)
CPC H02K 15/023 (2025.01) [H02K 17/20 (2013.01)] 27 Claims
OG exemplary drawing
 
1. A method for producing a squirrel-cage rotor of an asynchronous machine, said method comprising:
inserting conductor bars of a first conductive material into substantially axially running slots of a substantially cylindrically shaped magnetically conductive body, such that the conductor bars project out of at least one end side of the magnetically conductive body to form a projection;
axially positioning by cold joining a short-circuiting disc of a second conductive material under pressure on the projection of the conductor bars to form a contact area between the projection and the short-circuiting disc such that the projection has a clearance fit of approximately 0.1 mm or less relative to a radially outwardly open recess of the short-circuiting disc with gaps which initially exist at least between the projection and recesses of the short-circuiting discs;
heating, by hot-forming, the short-circuiting disc while the conductor bars almost simultaneously contact the short-circuiting disc, thereby causing the gaps to close; and
coating at least the projection of the conductor bars with a third material at a layer thickness to form an alloy at the contact area with the first and second materials after heating by hot forming so that the third material is fully dispersed in the first and second materials as a result of the third material being diffused into the first and second materials.