Closed die forging machine

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 function, are mechanically produced and controlled. Consequently, high cyclic operating speeds can be achieved.