OBRABOTKAMETALLOV Vol. 23 No. 3 2021 MATERIAL SCIENCE EQUIPMENT. INSTRUMENTS 5 2 3 mounted in its housing is rotated at an angle of inclination of the main cutting edge that is different from zero (l ≠ 0), the generating surface takes a concave shape, and with an increase in the angle l the curvature of this surface becomes larger. Moreover, the works [15, 16] show that the curvature of the generating surface of such cutters can be increased by turning the cutter along the direction of translation feed movement by the angle x, thereby implementing a scheme of oblique milling, for which it is assumed to use five-axis machining centers. Therefore, it is advisable to develop a milling cutter design by selecting the inclination angle of RPI’s main cutting edge, in which the balance of the generating surface curvature and the least curvature of the convex surface profile being machined will be reached. By rotating the milling cutter for the calculated angle x while milling, this balance will also be reached along the entire profile. The implementation of this approach requires studying the influence of the cutter parameters (diameter, angle of inclination of the main cutting edge) and the angle of inclination of the cutter along the direction of the translational feed movement x on the change in the curvature of the machined surface (principal radii of curvature). From the foregoing, the purpose of this study can be formulated as reducing the error in approximating the profile of the workpiece when it is machined by the touch method with discrete movement of interlocking side or end mills along the profile and, as a result, providing the possibility of increasing the tool approach increment along the formed profile to increase processing productivity. The objective is to carry out a theoretical study of changes in the curvature of the part surface machined during oblique milling with interlocking side mills equipped with RPIs, as well as to develop a method for determining the inclination angle of RPI main cutting edge of a milling cutter and the rotation angles of a milling cutter along the direction of translation feed movement, ensuring the best fit between the producing surface of the cutter and the surface of the part in its points of contact. Methodology To carry out this study, a model of a prefabricated milling cutter with a nominal diameter (d), consisting of one RPI installed in the mill body with a taper lead angle (j) and the side rake angle (l) was developed (fig. 3). а b c Fig. 3. Simulation scheme of sequential installation of the RPI in the milling cutter body: а – setting the taper lead angle; b – setting the side rake angle; c – installation according to a given diameter in the milling cutter body Х2
RkJQdWJsaXNoZXIy MTk0ODM1