US 12,348,079 B2
Motor core and method of manufacturing the same
Takaaki Tanaka, Tokyo (JP); Tomoyuki Okubo, Tokyo (JP); and Yoshihiko Oda, Tokyo (JP)
Assigned to JFE STEEL CORPORATION, Tokyo (JP)
Appl. No. 17/756,833
Filed by JFE STEEL CORPORATION, Tokyo (JP)
PCT Filed Nov. 18, 2020, PCT No. PCT/JP2020/043085
§ 371(c)(1), (2) Date Jun. 3, 2022,
PCT Pub. No. WO2021/124780, PCT Pub. Date Jun. 24, 2021.
Claims priority of application No. 2019-226786 (JP), filed on Dec. 16, 2019.
Prior Publication US 2022/0393520 A1, Dec. 8, 2022
Int. Cl. H02K 1/02 (2006.01); C21D 8/12 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/06 (2006.01); H01F 1/147 (2006.01); H01F 3/02 (2006.01); H01F 41/02 (2006.01)
CPC H02K 1/02 (2013.01) [C21D 8/1272 (2013.01); C21D 9/46 (2013.01); C22C 38/004 (2013.01); C22C 38/02 (2013.01); C22C 38/06 (2013.01); H01F 1/147 (2013.01); H01F 1/14775 (2013.01); H01F 3/02 (2013.01); C22C 2202/02 (2013.01); H01F 41/0233 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A motor core formed by stacking a plurality of motor core materials that are punched from an electrical steel sheet, each of the motor core materials comprising a punched end surface in which an appearance ratio of recrystallized grains with a grain size of 15 μm or less is 70%,
wherein the appearance ratio of recrystallized grains means a ratio of a total length in thickness direction of the recrystallized grains that appear on the punched end surface to a sheet thickness of the punched end surface.