Press and method of making same

Abstract

A metal working press having a base, a die set located over the base, and coaxial primary and secondary rams movable towards and away from the base to drive the die set through a working stroke and return it to an open condition. The die set includes upper and lower die assemblies and the upper die assembly is connected to the primary ram in such a manner as to prevent axial separation but permit lateral movement of the die set relative to the ram whereby the die set can be moved into and out of the press. The upper die assembly includes two die members which are relatively movable in the axial direction of the ram and the extent of that relative movement is preset by a lost motion mechanism existing in the connection between the primary ram and the upper die assembly and also by engagement between opposed surfaces of the two rams. An adjustable stop fixes the open position of the die set by cooperation with the secondary ram and a locking mechanism is provided to releasably hold the die set in the open position during removal from and replacement in the press. The rams are mounted in a cylinder which is connected to the base through side plates and each side plate has two part-cylindrical surfaces each of which engages with a complementary surface of the base and cylinder respectively, and those part-cylindrical surfaces are formed about a common axis.