Patent attributes
A lathe for machining optical workpieces, in particular spectacle lenses, comprises a fast tool arrangement and a workpiece spindle arrangement. A machine frame is cast monolithically from polymer concrete and on and in which all the functional surfaces, functional spaces and other cutouts are formed to their exact dimensions during the casting process. The machine frame upper part cast in one piece simultaneously covers the fast tool arrangement and the workpiece spindle arrangement and thus the machine bed in the manner of a covering hood. The machine frame is of compact dimensions, has a very rigid oscillation-damping machine bed and, in comparison with the rapidly moving elements of the fast tool arrangement, has a very large mass with a high center of gravity, which prevents the transmission of disruptive oscillations from the fast tool movement to the machine bed and thus to the workpiece spindle arrangement. The lathe can be manufactured in a cost-effective manner and allows the production of any spectacle lens optical surfaces with extremely high dimensional accuracy and surface quality. The achievable optical surface quality allows direct polishing by means of flexible or adaptable polishing tools, as a result of which considerable savings are made in the subsequent process. If suitably equipped with a cutter spindle arrangement, edge machining operations on the spectacle lenses can be carried out.
