公开(公告)号：US20220020531A1

公开(公告)日：2022-01-20

申请号：US17343941

申请日：2021-06-10

Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA

Inventor： Hiroto NAGAKI ,  Kazumichi NAKATANI ,  Kohei ISHII

IPC: H01F41/02 ,  B22F3/03 ,  B22F7/02 ,  B22F7/00

Abstract: A method for manufacturing a powder magnetic core, the method including: forming a soft magnetic powder (SMP) layer by putting an SMP having a surface on which an insulating coating film is formed into a space surrounded by a lower punch and a die; forming a pressed powder by compressing the SMP layer in the die by the lower punch and an upper punch; and causing the pressed powder and the die to slide relative to each other and then removing the pressed powder from the die is provided. In forming the SMP layer, a different powder different from the SMP is put into the space before and after the SMP is put into the space and a different powder layer having a spring back rate higher than that of the SMP layer by 0.6-1.1% is formed on upper and lower sides of the SMP layer.