Modeling and Simulation of Formed Milling Cutter for Screw Based on Non-instantaneous Envelope Method

According to the shape of screw, the spiral surface equation of screw was established; and through analyzing the relative motion between screw and formed milling cutter, find the contact conditions of screw and cutter, further deduce the meshing conditions of screw and cutter, and the contact line equation was established based on non-instantaneous envelope method. From the axial cross-section shapes which the contact line rotates around the axis of cutter formed rotary surface, the profile equation of formed milling cutter was established. Analyzing the causes of processing error after wear of formed milling cutter, the tooth back curve equation was established, finally got the profile equation of formed milling cutter have constant back edge. By interference checking for profile equation of formed milling cutter, ensure correctness of milling cutter profile.