As manufacturing industry of our country machine tool rise, numerical control machine tool already put in each to be in spare parts treatment and automation product line. It is future the join equipment with each big intelligence indispensable factory. Because the breed of numerical control machine tool is very much, gold cuts facility of equipment Ban gold two kinds big. Control principle, function and component according to its at the same time, undertook classified from different point of view, we machine medium function to reflect from actual part below give classification: One, the with nodding position control numerical control machine tool in treatment of department of spare parts aperture. Machine tool of numerical control of dot position control basically has punching machine of boring machine of numerical control drilling machine, numerical control, numerical control to reach 3 coordinate to measure machine, printed circuit board drill is machine tool of the simplest numerical control of dot position control. The numerical control machine tool that chooses position control is used at machining the aperture department inside plane, two reference axis inside plane of its control treatment (the feed that a reference axis is a direction moves) drive cutting tool and workpiece to move relatively, from bus of a coordinate (the feed that a reference axis is a direction moves) drive cutting tool and workpiece to move relatively, from position of a coordinate (coordinate is nodded) sudden shift arrives next coordinate position, control the 3rd reference axis to undertake cutting is machined next. This kinds of machine tool asks seat buy has taller fixed position precision, manufacture efficiency to rise, the machine tool uses the highest feed speed of set to undertake locating athletic, be close to fixed position to dot advancement classifications or fall continuously fast, so that low speed approach is terminal, what reduce athletic part thereby is inertial the fixed position error that rush too and causes from this. In deciding displacement to use a process, numerical control machine tool does not undertake cutting machining, do not have any requirements to athletic contrail. 2, answer in cutting treatment at controlling numerical control machine tool point-blank at most. Machine tool of linear control numerical control is controallable the feed rate with cutting tool or appropriate workbench, edge parallel undertakes at the direction of reference axis linear shift and cutting are machined, feed speed can be adjusted inside certain limits according to cutting condition. Linear pilot is simple and easy numerical control lathe, have two reference axis only, can use at processing step rod. Linear pilot CNC Milling has 3 reference axis, the milling of face of usable Yu Ping is machined. Contemporary modular machine tool uses servo of numerical control feed, drive head is taking feed of axial of edge of many axle box, undertake cutting is machined, it also can count machine tool of numerical control of a kind of linear pilot. 3, curve and outline pilot are complex the numerical control machine tool of the spare parts. The numerical control machine tool that cent of machine tool of outline control numerical control machines for planar outline and the numerical control machine tool that dimensional outline machines. The CNC Milling of the numerical control lathe that the numerical control machine tool that planar outline machines has part of turning curved surface and outline of milling curved surface, its process the outline form of the spare parts. The outline of the spare parts is OK by linear, circular arc or aleatoric and flat curve (wait like corkscrewed yarn of parabola, Archimedes) composition. Without giving thought to spare parts outline by why to plant line segment composition, normally with small Duan Zhi the line approachs curvilinear outline when treatment. Face of outline of milling of columnar milling cutter is used on CNC Milling when, numerical control system controls cutting tool center to be relative to workpiece inside unit time, y1i of mobile △ Xi, △ goes up in direction of two reference axis in the meantime, the Li of to workpiece synthetic displacement △ in cutting tool, nod I to move to nod J by the equidistant on-line of outline curve, give a paragraph of small linear IJ in the treatment on workpiece thereby, will approach the IJ circular arc on outline curve. Control Yi of Xi of △ of heft of two opposite displacement, △ continuously, can machine piece multistage the broken line of small linear composition will approach curvilinear outline. Yi of Xi of feed heft △ , △ , the deflection to spare parts outline measures the cutting tool center that by the mathematical formula that synthesizes curve of time of feed speed unit, outline R of radius of Y=f(x) , cutting tool reachs mental allowance δ to decide (the condition such as D=R+6) is affirmatory, calculate in real time by numerical control system obtain. Such operation calls interpolation operation and operation of compensation of cutting tool radius. With computation the two displacement heft of earning dictates two reference axis move at the same time respectively, means of this kind of control calls control of two coordinate linkage. When the spare parts of curved surface of turning of lathe tool of blade of circular arc cutting that is R with radius, also want to undertake interpolation operation and cutting tool radius compensate operation likewise. When the cutting blade lathe tool that uses radius R=0 undertakes machining, but the outline according to workpiece is direct operation, do not need to consider the issue of deflection of cutting tool center, reason need not have operation of compensatory of cutting tool radius, become interpolation operation only. Can have machine tool of numerical control of pilot of two coordinate linkage, also can have a place commonly with linear control. Those who provide figure is different on the machine tool that ① of method of the following kinds of treatment dominates two coordinate linkage in 3 coordinate, with " cut a way all right " undertake machining. Also have what call this kind of method two axes half control to make, namely two axes do the random in axis of X, Y, Z3 interpolation moves, the 3rd axis does periodic feed exercise, cutting tool uses ball head milling cutter, if pursue 1. 6 are shown. It is to cent in Y a certain number of paragraph, the curve of plane of ZX of edge of ball head milling cutter undertakes interpolation is machined, after a paragraph of treatment is over, feed △ Y, rework curve of another photograph adjacent, so ordinal will approach with flat curve whole in the radius of the △ Y requirement according to exterior surface roughness and knife head is chosen, the ball radius of ball head milling cutter should be chosen a few more greatly as far as possible, with reducing exterior surface roughness Ra is worth, increase cutting tool stiffness and medicinal powder hot property. But when machining concave side, head radius must be less than the ball to be machined the radius of the smallest curvature of curved surface, lest generate cutting blade interference. 3 coordinate linkage machines ② . Ball nut circulates inside time bead implement SS of its raceway generatrix is curve of a space, it can be approached with the space point-blank, can be in have a space the treatment on the bed of 3 coordinate linkage of linear interpolation function. But process designing calculation is more complex, its machine program can use system of automatic process designing to weave. 4 coordinate linkage machines ③ . Its machine shows plane crossbeam the surface is straight grain twist if the face uses machine tool of 3 coordinate linkage and treatment of ball head milling cutter, not only productivity is low, and the exterior surface roughness of spare parts surface is very poor also. In order to use means of cutting of periphery of columnar milling cutter, in the treatment on 4 coordinate machine tool, outside the linkage that divides 3 mobile coordinate, going up endlong to protect cutting tool and workpiece area from beginning to end joint, cutting tool still should circle O1(or O2) is done swing linkage. This swings linkage brings about linear and mobile coordinate to want to have additional compensation is mobile, its are add carry momentum and the position that place a heart are concerned, also need to have consideration when process designing. Machine program should decide the displacement of 4 reference axis dictates, in order to control four-axle linkage treatment, process designing is quite accordingly complex. 5 coordinate linkage machines ④ . All dimensional outline can be pressed with ball head milling cutter almost " cut a way all right " undertake machining. To a few large curved surface outline, the curvature radius of spare parts dimension and curved surface is bigger, convert face milling cutter undertakes machining, can increase the productivity, incomplete allowance that reduces treatment (reduce exterior surface roughness Ra is worth) , if pursue 1.
9 are shown. When the milling cutter that use a face is machined, the end panel of cutting tool and workpiece outline are in what cutting dot is in to cut planar coincide (machine convex) , or with cut plane to become some included angle () of treatment concave side, the normal parallel of axes of i.e. cutting tool and workpiece outline or into some included angle (this included angle can avoid to produce cutting blade to interfere) . When treatment, cutting nods P(X, y, the deflection θ of the coordinate that Z) is in and normal N is constant change, knife of reason cutting tool the deflection of the coordinate that nods O and cutting tool axes also should make corresponding change. Current numerical control machine tool is the mathematical model according to outline of spare parts curved surface when work out machine program, the knife that computation gives each cutting to nod correspondence the coordinate that nods O and deflection (namely knife digit occupies) , input numerical control system through the program, in order to control cutting tool. Knife the coordinate position of the dot comes true with coming by reference axis of 3 linear feed, the deflection of cutting tool axes can circle the corner that reference axis rotates twice to synthesize implementation by random. Accordingly, when the milling cutter that use a face machines outline of dimensional curved surface, need to control 5 reference axis (3 linear reference axis and reference axis of two circumferential feed) undertake linkage. The numerical control machine tool of 5 axes linkage is a function the machine tool of a kind of numerical control with the most complete, the most complex control, the to program that 5 axes linkage machines also is the most complex, should use system of automatic process designing to weave. Afore-mentioned classification basically are the treatment function that is based on numerical control machine tool. If will classify from the point of view that commands number of axle and linkage number of axle, numerical control machine tool can be divided for machine tool of numerical control of two axes linkage, 3 axle control bed of numerical control of linkage of machine tool of numerical control of two axes linkage, 3 axes reachs machine tool of numerical control of 5 axes linkage to wait. If this piece the article is helped somewhat to you, the welcome nods an assist to perhaps pay close attention to, thank you read, if you have better proposal, the welcome comments on an area to leave a message beneath. Pay close attention to CNC Milling of barbette milling machine, share knowledge of accurate machine tool with everybody everyday. CNC Milling