Patent ID: 10737310

Abstract:
An inner circle and outer periphery punching step is performed in which a punching process is performed on a plate material made of a metal material to form an outline on an outer periphery side and a circle space on an inner periphery side, thereby forming an intermediate plate material. In an inner periphery bending step, the intermediate plate material is subjected to a bending process of bending a portion inside of a base circle that is a circle between an inner circle end portion and an outer circle, toward one side. In an inner periphery punching step, the intermediate plate material is subjected to a punching process of punching out inner periphery radial portions that are portions radially extending from the inner circle end portion, to form inner periphery slits extending inside of the outer circle in respective radial pieces. In an outer periphery bending step, the intermediate plate material is subjected to a bending process of bending a portion outside of the base circle from the base circle toward the one side, thereby forming a spring member.