CNC screw milling machine is a newly developed screw processing equipment, which breaks the status quo of low processing efficiency and cumbersome processing process of traditional screw processing equipment, and adopts double milling head to process at the same time, shorten the production cycle, reduce production costs, improve production efficiency, and enhance the competitiveness of enterprises. First of all, the data were collected, and by analyzing the development status of CNC milling machines at home and abroad, and in view of the shortcomings of existing research, the overall design scheme and hardware selection of double-head CNC screw milling machines were studied, and the motion control system and CNC servo system were mainly analyzed. Secondly, the hardware part of the double milling head* CNC screw milling machine, the design and technical parameters of the screw, the milling parameters and geometric elements of the cutter were analyzed. Then, the double milling head * screw milling machine processes the screw, in order to process the spiral profile of the workpiece, the radius compensation function is selected to realize the movement trajectory of the tool during the contour CNC milling processing.
The theoretical basis for the formation of the spiral surface is based on the principle of meshing, the surface of the milling cutter and the surface of the workpiece are a pair of conjugate surfaces, and the rotating surface of the cylindrical milling cutter and the spiral surface of the workpiece are in relative motion for a moment, and there is always a tangent contact line between the two surfaces. The contact line can be understood as fitting with enough contact points, and each contact point does a spiral motion around the axis of the workpiece, and what is obtained is each spiral line in the helix surface of the workpiece, and the spiral movement of the contact line can form a spiral. Through the analysis of the meshing surface, a mathematical model was established, and the experimental analysis and processing were carried out by MATLAB software.
Finally, due to the occurrence of abnormal conditions such as power failure in the machining process, the tool needs to be repositioned at the tool stop position, and the accuracy of positioning directly affects the machining accuracy of the screw. Because the knife into and out will produce a backlash, this backlash is the key to affect the determination of the knife precision D, the use of LabVIEW software to write the program of measuring and compensating the backlash, to achieve the precision D determination of the knife.
Machining