Patent · US Expired

Closed die forging machine

US4779444A · kind A · utility

1Cited by
5References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 12, 1987
Grant dateOct 25, 1988
Priority date
Expiry dateMar 12, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB21J13/14
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A closed die forging machine is disclosed in which the dies are clamped in their closed position by a hydraulically operated piston and cylinder means. A spacer is positioned between the clamping means and the movable die during the forging operation. Subsequent to the forging operation, the clamping means are released and the spacer is removed so that the movable die can be mechanically moved to its fully open position. By combining a removable spacer and hydraulic clamping means, it is possible to produce high die clamping forces without requiring substantial fluid flow to and from the clamping means. Therefore, pumping requirements are reduced and the tendency of the hydraulic fluid to become excessively hot is substantially reduced. Immediately after the completion of the forming operation within the closed die cavity, the hydraulic forces are released and a spring-powered system controlled by a cam-operated operator causes partial ejection of the finished workpiece from the stationary die. This minimizes the tendency of the fixed die to be excessively heated by the workpiece and improves die life. All of the operating functions, with the exception of the hydraulic clamping fun…

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