METHOD AND DEVICE FOR MACHINING GLASS AND VITREOUS MATERIAL AS WELL AS WORK-PIECE OF GLASS OR VITREOUS MATERIAL MACHINED ACCORDING TO THE METHOD

8.11.79 1 PHN 9306 Method and device for machining glass and vitreous material as well as work-piece of glass or vitreous material machined according to the method. Method and device for machining glass and vitreous material transparent by means of a single point cutting tool, a portion of the work-piece to be worked being heated integrally and uniformly by a first spread heat supply to the softening temperature and simultaneously the surface to be worked being locally heated in the region of the cutting area-at the moment of material removal and to a depth equal to the cutting depth by a second concentrated heat supply, which is superimposed on the first heat supply, all this in such a manner that a chipping operation as well as simultaneously therewith and immediately thereafter a relaxing flow of the worked surface takes place. By means of the method according to the invention it is possible to chip work-pieces of glass and vitreous material so that the worked surface has a high dimensional accuracy as well as an optical surface quality in particular, that is to say a smooth, and transparent surface.