Abstract: A rock drill for rotary blow drilling with a drilling head arranged at the free end of the drill shaft, which at least partially consists of hard metal. The drilling head the end face of which is circular disc shaped or circular ring shaped includes a formed piece of solid hard metal. Cutting bodies are machined out of the end of this piece of hard metal which cutting bodies have the shape of pyramids or truncated pyramids and taper with increasing distance from the drill shank.

Abstract: A milling cutter, especially contour milling cutter, which comprises individual cutting elements helically arranged around the axis of the cutter body and connected thereto. These cutting elements are separated from each other in circumferential direction of the cutter body by chip grooves. All of the chip grooves extend helically about the axis of the cutter body in the same sense. Webs project from the cutter body and extend in the same sense helically about the axis of the cutter body while being separated from each other by the above mentioned chip grooves. Along the outer web edges which are located on a common cylinder mantle there are provided depressions or cutouts separated from each other by web sections which form the individual cutting elements.

Abstract: A drill for electronic conductor plates with a cylindrical drill head which is arranged at the front end of a shank, and which in particular has a working diameter of from 0.5 to 1.2 mm. The rear end of the cylindrical drill head is in the direction toward the drill shank followed by a first shank section of a shorter outer diameter. The drill head and the next following first shank section comprise guiding passages for the drilled out material, especially continuous helical grooves in the manner customary with spiral drills. The drill is characterized primarily in that the first shank section adjacent the drill head conically tapers from the rear end of the drill head in the direction toward the rear end of the drill shank.