Abstract: An adapter for use with clamping devices for clamping workpieces on perforated screen plates of machine tools. The adapter has a plurality of building block-like elements. One such element, a base plate, has at least two bores for fastening the base plate to the perforated screen plate. A T-groove in the base plate receives a transverse sliding element. A T-groove in the transverse sliding element receives a base of a longitudinal sliding element. A building block element rests on the base plate. A securing mechanism secures the building block-like elements with respect to each other.

Abstract: A sheet metal working device comprising a movable carrier supported between two side panels of C-shaped form. The carrier has the form of a bar which may be mechanically moved by a drive means and which at its top portion is connected to a sharpened piece which serves as a movable blade and acts together with a replaceable stationary blade as shears. A holding device is disposed on the lower portion of the carrier which holds the top tool of a stamping device or a folding press. The sheet metal working device may operate as a stamping device or folding press.