The classification of numerical control machine tool has a variety of kind. (1) by machine tool numerical control athletic contrail differentiates● chooses machine tool of position control numerical control: Point to when cutting tool moves, control cutting tool appearance only the accuracy to workpiece displacement, take no account of the method between 2 o’clock, exactly the amount controls drilling machine. ● chooses a machine tool of linear control numerical control: On the foundation that nods position control, assure to move even linear, and cutting tool undertakes in athletic process cutting is machined even. ● outline controls numerical control machine tool: Can be opposite two or more coordinate motion undertake controlling (much coordinate linkage) , contrail of cutting tool motion can be dimensional curve. In mould industry this kind of machine tool applies most, be like the numerical control mill of 3 coordinate above or machining center. (2) by servo control means differentiates● open loop controls a machine tool: The price is low, precision and stability are poor. ● machine tool of numerical control of half closed-loop control: Precision and stability are taller, price moderate, application gains ground most. Machine tool of ● closed-loop control numerical control: Precision is tall, stability is controlled hard, the price is high. (3) differentiate by linkage coordinate number of axleTwo axes of ● machine tool of linkage numerical control. Two axes make the random in axis of X, Y, Z3 interpolation linkage, the 3rd axis makes alone periodic feed, often call 2.5 axes linkage. If the graph is shown 1 times, become X to cent a certain number of paragraph, the curve of cut of place of face of YZ of edge of round head milling cutter undertakes milling, each paragraphs machine junior X giving Δ , rework curve of another photograph adjacent, so ordinal cutting can machine a whole curved surface, reason is called cut a way all right. According to the surface bright and clean the principle of surface of hands-off photograph adjacent chooses degree of head that reach a knife Δ X. The cutting tool that cuts a law to machine place to use all right is ball knife milling head normally (point to shape milling cutter namely) . Machine curved surface with this kind of cutting tool, interfere photograph adjacent surface not easily, calculation is simpler. The knife head radius of bulbiform milling cutter should be chosen a few more greatly, be helpful for improving treatment bright and clean degree, increase cutting tool stiffness, medicinal powder heat. But the radius of the smallest curvature that knife head radius should be less than curved surface. Graph 1When milling cutter of the head that use a ball machines curved surface, the data that always uses knife heart contrail undertakes process designing. The graph shows the knife heart contrail that for 2 axes linkage 3 coordinate cut a law to machine all right and cutting 2 times to nod orbit sketch map. ABCD is by treatment curved surface, p plane makes a parallel range of the surface at YZ for parallel, of the equidistant face IJKL that O1O2 of contrail of its knife heart is curved surface ABCD and Pyz of travel tangent plane cross a line, apparent, o1O2 is a flat curve. Below this kind of circumstance, the position that ball head knife and curved surface cutting can cause to nod when the curvature of curved surface changes also is changed subsequently, and the Ab connecting a line that cutting nods is curve of a space, form screwy rudimental channel grain on curved surface thereby. The knife heart contrail that machines as a result of 2.5 axes coordinate is flat curve, calculation of reason process designing is relatively simple, device of numerical control logic is not sophisticated also, change of rate of commonly used Yu Qu is not big and the rough machining with precision not high demand. Graph 23 axes of ● machine tool of linkage numerical control. Axis of X, Y, Z3 but at the same time interpolation linkage. When machining curved surface with 3 coordinate linkage, also use normally cut a method all right. If the graph is shown 3 times, the course of numerical control knife of 3 axes linkage can be flat curve or dimensional curve. The accurate treatment that 3 coordinate linkage machines miscellaneous curved surface of commonly used Yu Fu (be like accurate forging die) . But process designing calculation is relatively complex, uses numerical control device still must have function of 3 axes linkage. Graph 3Machine tool of numerical control of ● four-axle linkage. Besides translation of axis of X, Y, Z3, still have workbench or the roll of cutting tool. If the graph is shown 4 times, flank twists curved surface for straight grain. When if be on the machine tool of 3 coordinate linkage,milling cutter of the head that use a circle presses a treatment that cut a way, not only productivity is low, and bright and clean spend difference. For this, use cutting of periphery of columnar milling cutter, use treatment of 4 coordinate milling machine, outside moving except 3 rectangular coordinates namely, be in to assure cutting tool and workpiece face full-length from beginning to end joint, cutting tool still should circle O1 (or O2) make the linkage that place part. Because place horny motion, bringing about rectangular coordinates is (the Y in the graph) need add exercise, calculation of its process designing is relatively complex. Graph 45 axes of ● machine tool of linkage numerical control. Besides the translation of axis of X, Y, Z3 still cutting tool rotates, the whirl of workbench. Airscrew is one of typical spare partses that 5 coordinate machine, its lamina appearance and treatment principle are shown 5 times like the graph. The with face of blade AB crossing a line on the round cylinder that is Ri in radius is the one part of corkscrewed yarn, helix angle is φ I, the radial leaf molded lines of blade (axial section plane) the dip after the obliquitous α of EF is. Corkscrewed yarn AB machines a method with polar coordinates and approach in order to lose line segment. Approaching line segment Mn is by C coordinate rotates the synthesis of Δ θ and Z of Δ of Z coordinate displacement. After AB is machined, x of Δ of cutting tool radial deflection (change Ri) , the another leaf molded lines of rework photograph adjacent, ordinal one by one is machined, can form whole face of blade. Because the curvature radius of face of blade is bigger, so milling cutter of commonly used end panel is machined, simplify in order to improve productivity program. Accordingly, to assure milling cutter end panel from beginning to end with curved surface joint, milling cutter still should make coordinate A and coordinate B form the campaign placing part of θ T and α T, placing part while, return the add motion that should make rectangular coordinates, be worth in order to make sure center of milling cutter end panel is in process designing from beginning to end locally, need coordinate of Z, C, X, A, B5 to machine so. The process designing calculation of this kind of treatment is quite complex. Graph 5● machining center. It is knife library is configured on numerical control milling machine, all sorts of cutting tool that depositing different amount among them or check are provided, be chosen automatically by the program in machining a process and change, thereby milling, boring, auger cut, attack the function such as whorl to be centered on an equipment to finish, make its have a variety of craft mediums.