FIELD: machine engineering, automobile manufacture, machine tool manufacture, aircraft industry, tractor and crane manufacture, production of power outer involute cylindrical gearing for drive units, gear and feed boxes. SUBSTANCE: worm milling cutter includes involute cylinder-shape worm with helical grooves for chip and for forming on lateral faces of teeth cutting edges whose profiles are similar to those of teeth of initial contour of involute gearing in normal cross section of worm. Outer boundary straight line of said initial contour is shifted towards axis of milling cutter at stages of its designing and making. In order to provide necessary value of said shift for eliminating undercut of profiles of teeth of involute cylinder gear wheels (it allows to make gear wheels with factor of shift of initial contour equal to zero without undercut of profiles of teeth with any small tooth number), coefficient of height of tooth head of initial contour of worm milling cutter and coefficient of boundary height of initial contour of worm milling cutter are determined according to given formulae in dependance upon profile angle of tooth of initial contour in portion between boundary straight lines of contour for gear wheels with straight teeth, tooth number, profile angle of tooth projection of initial contour of worm milling cutter on end plane of gear wheels with oblique teeth and inclination angle of oblique teeth in indexing cylinder of wheels. EFFECT: improved design. 3 dwg
