ALEXANDRIA, Va., Sept. 10 -- United States Patent no. 12,409,487, issued on Sept. 9.
"Method for manufacturing ring member for bearing, and mold for inversion working" was invented by Kenji Tezuka (Takasaki, Japan) and Nobuyuki Hagiwara (Takasaki, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A method for manufacturing a bearing ring member includes an inversion step of deforming a workpiece having an annular shape by sandwiching the workpiece between a punch disposed on a first side in a predetermined direction and a die disposed on a second side. The punch has a first R surface formed in a circular arc shape. The die has a second R surface formed in a circular arc shape, and a tapered surface inclin...