Self-leveling die platen for die stamping presses

In a die set including first and second, opposed, relatively shiftable cooperating die platen assemblies, at least one of which has a die for operating on a workpiece placed between the platen assemblies, the improvement which comprises a self-leveling assembly for one of the platen assemblies, said self-leveling assembly comprising:

• a shoe having a cavity region presenting a fluid reservoir;
• a piston having an outer main surface and an inner surface parallel to the outer surface, said piston being rockably positioned within said reservoir in disposition resting on and in direct contact with the fluid therein;
• and
• an adjustable platen presenting an operating face and an opposed mounting face, said adjustable platen being carried by said piston with the main surface of the piston engaging at least the central area of the mounting face of the adjustable platen,
• said piston and adjustable platen being freely rockable as a unit about two perpendicular axes both parallel with said platen operating face to automatically adjust the orientation of said adjustable platen operating face with respect to the opposed platen assembly to maintain parallelism between the work engaging parts of the platen assemblies at the time each time said at least one die is brought into an operating position against the workpiece.