Patent ID: 6135892
Filing Date: 2000-10-24
Classification: B21H,F16B

Abstract:
A method of forming a member comprising:providing a blank having a head and a cylindrical shank extending therefrom;providing a pair of rolling dies, each said die having a threaded portion, a threaded transition portion which has at least one truncated thread thereon and an unthreaded radiused portion, said threaded transition portion being between said threaded portion and said unthreaded radiused portion;machining an end of said cylindrical shank to form a predetermined form thereon and to define a machined blank; androll threading said machined blank using said rolling dies, whereupon a first portion of said machined blank which is rolled between said threaded portion of each said rolling dies is threaded, a second portion which is rolled between said transition portion of each said rolling dies is threaded, said threaded transition portion forming threads having major surfaces which have a substantially spherical profile, and a third portion of said machined blank which is rolled between said unthreaded radiused portion of each said rolling dies remains unthreaded.