New technological solutions for the manufacturing and sharpening of three-flute drills

Abstract

In high-precision mechanical engineering, the need for small-sized products has been steadily increasing over the past decades and, thus, small-sized cutting tools are used for their production. Laser processing has become one of the most convenient and effective technologies. A new approach to manufacturing micro-cutting three-prong drills is based on the laser ablation technology, which allows to remove material from the workpiece surface regardless of its and has a small zone affected by heating. Laser ablation does not cause workpiece deformation or wear, which ensures high precision of shaping. The work presents a special technology of continuous impact on a section of the front and rear surfaces when forming a sharpening in the form of a set of B-splines. The splines are arranged in such a way that, as a result of removing material from the end of the drill, the cutting wedge forms an angle close to constant with a minimum duration of laser exposure, ensuring in this way the edge. Thus, the algorithm allows forming the working part of a three-tooth drill depending on the diameter, offset of the cutting edge, angle of inclination of the helical flute, front and rake angles of the blade. The new technology allows, for the first time, to form a point and back surface with constant angles on microcutting three-tooth drills with a minimum duration of laser exposure, in particular, when restoring restoration or cyst pointing of the cutting part of the drill. Unlike the known model of the tool is not discredited by the edge sections and the formation of the standard form of the flank surface, but creates geometry along the freely formed cutting edge. The goal of minimizing the number of necessary physical tests while expanding the capabilities of the modeling results is achieved. The mathematical model of the process of forming the main rear surface of the drill will ensure the constancy of the normal clearence angle along the cutting edge of an freely shape.