Patent · US Expired

Method and apparatus for producing fasteners having wrenching sockets therein

US4805437A · kind A · utility

12Cited by
8References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1987
Grant dateFeb 21, 1989
Priority date
Expiry dateDec 21, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB21K5/16
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method and apparatus are disclosed for forging a wrenching socket in the end of a fastener which permit the production of such fasteners from materials which are difficult to forge, such as titanium and some high strength steels. A cylindrical preliminary socket is formed in the end of the blank forming the fastener with a punch having a circular cross section. The preliminary socket is sized to be at least as great as the maximum lateral dimension of the finished wrenching socket required. Subsequently, a tool having a cross-sectional shape corresponding to the required finished socket is positioned in the preliminary socket and the material of the blank is extruded inwardly against the tool to form a cylindrical exterior surface and a finished socket having a non-circular cross section. With this invention, even very small hexagonal sockets can be formed in titanium fasteners. The particular illustrated embodiment also utilizes warm-forming, in which the blank material is heated to a temperature in the range of 1200.degree. to 1400.degree. F. before being formed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.