PROBLEM TO BE SOLVED: To appropriately manufacture an arc-shaped rail which is C-shaped in a cross section and includes an arc-shaped inner circumferential wall, an outer circumferential wall, a pair of side walls connecting both circumferential walls at the side edges, and a slit formed along the longitudinal direction in the central part of the inner circumferential wall or the outer circumferential wall by using a thin metal plate.SOLUTION: A manufacturing method of an arc-shaped rail includes: a first process of forming the side wall 313 and one of divided circumferential wall portions 312 on both sides in a width direction of the inner circumferential wall or the outer circumferential wall divided by the slit by bending a ring R of the thin metal plate by spinning a second process of forming the other side wall 313 and the other divided circumferential wall portion 312 by spinning by using a plurality of cores 41-43 obtained by dividing a core in a width direction to be equal to or less than a width of the slit 314 in a manner to envelop the cores 41-43 and a third process of separately extracting the plurality of cores 41-43 from the slit 314.COPYRIGHT: (C)2012,JPO&INPIT【課題】円弧状の内周壁及び外周壁と、両周壁をその側縁で連結する一対の側壁と、内周壁又は外周壁の中央部に長手方向に沿って形成されたスリットとを有する断面C字状の円弧状レールを、金属製薄板を用いて適切に製造する。【解決手段】金属製薄板状のリングRをスピニング製法で折り曲げることにより側壁313及びスリットにより分割された内周壁又は外周壁の幅方向両側の分割周壁部分312の一方を形成する第1工程と、スリット314の幅以下に幅方向に分割された複数の中子41~43を用いて、中子41~43を包み込むようにして、スピニング製法により側壁313及び分割周壁部分312の他方を形成する第2工程と、スリット314から複数の中子41~43を個別に抜き去る第3工程とを備える。【選択図】図3
