ALEXANDRIA, Va., July 14 -- United States Patent no. 12,683,061, issued on July 14, was assigned to JFE STEEL Corp. (Tokyo).
"Laminated core" was invented by Takeshi Omura (Tokyo), Yoshihisa Ichihara (Tokyo) and Souichiro Yoshizaki (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "A laminated core includes a stack of pieces of an electrical steel sheet that have a predetermined shape resulting from processing and includes a butted portion at which portions of a processed surface of the electrical steel sheet are abutted against each other. In the electrical steel sheet, an area ratio of regions of the processed surface that have an arithmetic mean roughness Ra of 5 micro metre or less is 90% or greater b...