MasterCAM in blade spare parts 4 linkage CNC Machining applies

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One, foreword CNC Machining is a kind of programmable flexible machine a method. Numerical control machine tool is siding with high speed, high spirit, Gao Rou gender, compound sexual way develops, its cost is relative taller, reason applies to precision tall, the treatment of the part with complex form, and band of public errand of blade spare parts is small, its model the face is complex dimensional curved surface more, need makes appropriative tool fixture, into batch production asks to duplicate accurately, it is the applied object of CNC Machining all the time. 2, the work that processing technique of linkage of four-axle of machine tool of 4 linkage NC basically uses at treatment to have relatively complex curved surface, machine photograph comparing with 3 axes linkage, four-axle linkage treatment can be machined piece more high quality, more complex curved surface, basically apply to the special treatment of the industry such as plane, mould, car, had gained ground at present homebred 4 coordinate machine tool. Following different picture institute show machine tool of NC of 4 coordinate vertical is one runner shaft coming back increases on the foundation of axis of 3 linear translation. Following plan institute show its kinematic chain (graph 1) . Graph 1 3, the structural characteristic of blade pursues the 2 structures from blade (graph 2) in light of, part of its leaf body face is complex dimensional curved surface, the curvature of departmental cent, reverse change bigger, the Bao Bi that is a model. Because its are the important part of the device such as motivation, working requirement is relatively abominable, the very tall requirement that raises to the precision of spare parts itself and quality. Model the treatment quality of the face affects its character of service directly, affect overall performance possibly thereby. The material of blade asks to have very high quality, intensity comparing, in treatment difficult cutting, cutting fights muscularity, cause be out of shape big also. Because its are sectional appearance, ability of counteractive on foliaceous basin and foliaceous back direction metabolic is different also, the brim that take a platoon is in thinner, the deformation in treatment is very complex. Raised very tall requirement to CNC Machining. In be machined actually, use the following treatment technological process more, if pursue,3 are shown. Graph 3 4, the software of a CAD/CAM that the CAD of blade builds modular Mastercam is development of American CNCSoftware company, the earliest version is V3.

0, can use at DOS. Because its are born earlier, hold the main function that provides CAD software and CAM software concurrently, development is the one branch strange flower in CAD/CAM software undoubtedly up to now, very high market is had rate. The CAD function of software is OK scale 2D and 3D graph, the function that compose builds free curved surface is the CAD software with far congener outclass more; The CAM function of software is convenient and intuitionistic, can be directly on dot, line, curved surface, substance generation knife course, the freedom that its postposition transaction file is type of answer of a kind of user alters a document, mpfan of acquiescent postposition transaction file.

Pst and the NC machine tool that FANUC controls a system are not had seam compositive. 1. Compose builds sectional line to give data scale to give the sectional clue on each plane by the design, foliaceous basin and the molded lines that the leaf carries on the back all are free curve, it is a paragraph of circular arc into exhaust brim, transfer each curve glossily, what assure each paragraphs of curve is successive. The basis is given the curve that turns round horn to board each plane passes Xform, Rotate command undertakes gyral, get curve of a group of spaces, following plan institute are shown (graph 4) . Graph 4 2. The sectional line that compose builds curved surface to go to earning is founded through Create() , Surface(curved surface) , Loft (lift litre) operation, can get the foliaceous body of blade area, sectional amount will affect the smooth compliance of curved surface, pair of neat pattern that adjust each several foothold, with curved surface public errand, get as follows pursueing (graph 5) what show 3 rank NUBS curved surface. Graph 5 5, treatment of the CAM treatment lamina of blade face can be on machine tool of numerical control of 3 coordinate, 4 coordinate, 5 coordinate treatment is finished, uses cutting tool has bazoo of knife of ball head knife, flat bottom, ox knife, annular knife, bosomy form knife, cone-shaped knife, but according to curved surface freedom of main shaft of abrupt degree, machine tool is spent, the cutting tool that treatment asks to choose to suit. 1. The advantage that machine tool of 4 coordinate numerical control face machines is in before model 3 coordinate treatment is used more in face treatment, its feature is treatment axes is changeless from beginning to end. Namely parallel at Z reference axis. Treatment of 3 coordinate curved surface is machined through walking along a knife to finish line by line. Cutting tool moves along what each cutting goes, approximately bag sth resembling a net machines curved surface, row spacing is the main factor that affects treatment quality and efficiency. Too big row spacing will make exterior remains too big, the workload of follow-up working procedure greatens, too small row spacing can make the twice of machine program and time increases. Take knife means and part among them the main factor that the attitude of opposite cutting tool is influence row spacing. It is a few 3 coordinate are commonly used kinds of means taking a knife below. Graph 6 it is an edge sectional direction takes a knife, this kind of means taking a knife can obtain better outline to spend, the impact that row spacing gets is little also, but dot of cutting tool cutting is ceaselessly of acuteness change, mental allowance also manages next constant change relatively, produce adverse effect to cutting tool and machine tool. Graph 6 graphs 7 take a knife along cutting direction, have taller efficiency, be in actually medium applying more. But the law arrow that nods as curved surface cutting and cutting tool axes (Z reference axis) included angle increases, exterior remains increases, the abrupt degree of curved surface and the installation trend that its get on in clamping apparatus are very subtle to row spacing. Graph 7 graphs 8 it is annulus cuts way, be before two kinds of means is integrated, basically apply those who be restricted at border to suffer model face treatment, from inside when be being cut to outer shroud, of position of cutting tool cutting all around can be supported by the tigidity of semifinished product, advantageous decrease be out of shape. Graph treatment of 8 four-axle linkage can solve afore-mentioned problems, effectively control cutting tool and curved surface cutting nod the included angle of law arrow, make cutting surplus relatively even thereby, in model the face turns round bigger lamina there is clear advantage in treatment; Completed the back of foliaceous basin, leaf, treatment that receives exhaust brim at the same time, have taller treatment precision. 2. Of blade model of face treatment lamina model the face is free curved surface, semifinished product is modular forging, need has semifinishing machining and precision work. OK in semifinishing machining the basis is generated to slant by the face of treatment buy side. Method of cutting tool of the Toolpaths(in using Mastercam) , Multiaxis (much axis is machined) , Msurf5ax (5 axes curved surface is machined) , choose curved surface drive, cutPattern(cutting mode) , ToolAxisControl(knife axle control) , CutSurfaces (cutting curved surface) choose to be machined curved surface. Choose a diameter to be the ball knife treatment of 12, semifinishing machining step pitch takes 1mm, finish machining step pitch is taken 0.

3mm, surplus is 0.

2mm, screw type takes a knife. Following plan institute show the knife course way of finish machining (graph 9) . Graph 9 3. Treatment is emulated to examine the validity of knife course, the phenomenon is cut too in preventing to machine, mastercam provided function of powerful emulation desired result. Install through Jobstup(semifinished product first) dimension of setting semifinished product, use Verify(desired result) the function emulates cutting, following plan institute are shown (graph 10) . Graph 10 4. Cent of system of postposition processing Mastercam gives priority to processing program and postposition processing program two much. Advocate processing program is aimed at treatment object, treatment system builds 3D model, contrail of computational cutting tool, make NCI file (file of cutting tool method) . NCI file is a document that compiles the full data that includes NC program with ASCII code. Postposition processing system configured the general aftertreatment that gets used to onefold type to control a system, this postposition processing provided model of database of a kind of function, the user is mixed according to numerical control machine tool the particular case of numerical control system, can undertake revise and be compilinged to its database, custom-built a program of special postposition processing that gets used to machine tool of some numerical control. The patulous name of its file is PST, defined cutting to process form of form of parameter, NC, auxiliary instruction, interface function. Acquiescent MPFAN.

PST is decided at the higher level but not officially announced becomes the current form that gets used to FANUC controller, wait like FANUC3M, FANUC6M, FANUC0-M. Through Postprocessing (postposition is handled) operation, the system produces NC form automatically, following: 5. The correction feed speed of feed speed machines quality of quality, treatment precision, surface to having main effect to blade. The hope when finish machining can carry constant cutting rate, as a result of the change of blade face, the career that cutting chooses also is in constant change, following plan institute are shown (graph 11) . Graph 11 basises of blade sectional and OK the curvature change pattern that analyses blade: Foliaceous basin and the curvature change that the leaf bears direction to go up are even, in treatment, the roll of axis of A of runner shaft coming back is slow, the distance of XYZ axis is short also, at this moment athletic rate is very rapid; The curvature change that manages into exhaust edge is acuteness, what axis of the A in treatment rotates is very fast, the distance of XYZ is very great also, such meetings bring about raise to take inadequacy of systematic drive power, make systematic whole rate falls. Numerical control process designing often gives out only the referenced value that machines speed, good case falls to be finished automatically by numerical control system, make numerical control process designing need not consider the metabolic case of speed, get used to effective treatment. But all be small straight line segment as a result of the machine program of blade curved surface, implementation speed is flowing should read beforehand ahead of schedule multistage, this controls a system to have very high processing rate with respect to the requirement, high-grade system already had such capacity. Have G93 feed to lead control when numerical control system when the instruction (speed is reciprocal, execute the time that this block uses) , can achieve rate of constant surface feed with G93 means directly. (can revise Mpfan of Mastercam aftertreatment file.

Pst makes the NC form that contains G93 statement form) , do not have G93 in the system can weave appropriate aftertreatment file is opposite when the instruction trends of machine tool rate is amended, make in the Xie Penxie with curvature little change back office lowers cutting feed rate, in curvature change enters the place side exhaust greatly to raise cutting rate, will compensate inadequacy of machine tool power. 6. DNC (direct control) because amount of blade face program is large,machine, the capacity of magnetism bubble memory of NC machine tool is finite, commonly used PC and communication of interface of RS232 of NC machine tool. The Communications(communication in passing Mastercam) function, format of setting transmission file, string together a mouth, desired result of transmission rate, odd even, data wait to realize online treatment consistently thereby with the parameter of CNC controller, following plan institute are shown (graph 12) . Graph 12 6, the four-axle linkage CNC Machining of last word lamina, relatively before 3 coordinate treatment, complete the treatment of foliaceous body face, reduced the workload of follow-up polish working procedure greatly, rose to machine quality and manufacturing efficiency greatly, raised the utilization rate of equipment at the same time. Mastercam applies successfully at the 4 linkage of blade to machine with its powerful function, better land solved the batch of this kinds of spare parts to produce medium quality and efficiency problem, obtained good economic benefits. CNC Milling CNC Machining