With lathe of ordinary numerical control accurate treatment generatrix is the workpiece of the curve that be not a circle

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Summary: Debated the interpolation technology point that with lathe of ordinary numerical control accurate treatment generatrix is workpiece of the curve that be not a circle, wove current machine program makes software. Need to input the bus equation of workpiece and geometrical parameter this software only, can create NC code machine program, can machine whole process in imitate of the animation on the computer. This software application obtained favorable result at lathe of GSK-928 numerical control is machined. 1 foreword is common the memory of numerical control system of numerical control lathe is finite, computational function is insufficient, when planning to add up to treatment curve, can use linear interpolation and circular arc interpolation only commonly two kinds of means. Accordingly, when with lathe of ordinary numerical control treatment generatrix is the workpiece of the curve that be not a circle relatively difficult, especially work of more complex to a few generatrix and more expensive to appearance precision requirement the curve that be not a circle, its treatment difficulty is greater. To simplify bus is the machine program work out of workpiece of the curve that be not a circle, raise the treatment accuracy to this kinds of workpiece and adaptability, the article puts forward a kind to be the accurate treatment method of workpiece of the curve that be not a circle in the light of bus, wove corresponding current machine program makes software, via actual on numerical control lathe application, the result is favorable. When the 2 technical points that increase interpolation precision choose means of circular arc interpolation to machine curvilinear interpolation means in the choice, because the curve of linear interpolation means delimits section is counted must enough much talent assures to machine precision higher, because this takes up memory is older. Be opposite for give attention to two or morethings all sorts of versatility that machine a curve, reasonable use memory, assure to machine precision higher, use means of circular arc interpolation more advantageous. The curvature circle that serves as curve of interpolation round radius in order to wait for each average curvature radius of small curve inside chord curve to go up some a little bit and curve have identical tangent and curvature in this bits. The curvature radius that uses each line segment that has differentiated regards circular arc interpolation as radius, can make radius of circular arc interpolation from beginning to end with the curve it is better to curve degree be identical, assure taller interpolation precision thereby. Accordingly, beg taking accurate curvature radius is the key that assures interpolation accuracy. If grow in order to wait for coordinate to undertake differentiating to the curve, criterion to the edge this coordinate is inhomogenous metabolic curve, the curvilinear appearance change that its order in different coordinate nots allow to ignore to the influence of curvature accuracy. For this, we used edge curve to move toward the method that undertakes with waiting for chord the curve differentiates. Because this paragraphs of curve is in order to pass again the average curvature radius of a lot of small line segment of fractionize regards his as curvature radius, so although the bigger to rising and fall, curve with very inhomogenous change, it is better to also can be obtained plan to combine the result. Show a method to be the operation ability with fast, accurate computer of have the aid of actually, those who use minimum increase by degrees the quantity differentiates the curve is calculated the curvature radius of each paragraphs of small curve, the linear distance that orders earnings start and appoint length photograph to compare, once achieve,formulary chord produces an interpolation drop namely when length, computation gives the average curvature radius of all this paragraphs of small curves to regard circular arc interpolation as radius its. Serve as this a little bit again next new the start of line segment of a paragraph of music, seek next interpolation site. Such analogize, till will whole curve differentiates,end. The first-order derivative Y that the curvature radius Pi that small curve nods each and the P of average curvature radius that wait for chord music line segment each can pass end points of each small music line segment and 2 rank derivative Y" computation is gotten, namely the M in type -- when the work with higher demand of paragraph of several treatment precision inside music line segment, should use lesser chord to undertake differentiating, in order to increase interpolation point, raise a curve to plan to combine precision. Of course, need to ask to have integrated consideration to memory of numerical control system and craft when particular operation, in an attempt to achieves optimal treatment result. The concave and convex sex of each circular arc can pass the curve compare this line segment the case numerical value of the average that function of two end points is worth and midpoint of this line segment undertakes judging, if [F(x1)+ F(x2) ] / 2 <f[(x1 + X2)/2] , criterion the curve between X1 and X2 is on protruding, if [F(x1)+ F(x2) ] / 2>f[(X1 + X2)/2] , criterion the curve between X1 and X2 is below sunken. Graph reasonable design takes schematic diagram of 1 direction taking a knife because knife direction is common the memory of numerical control system of numerical control lathe is finite (it is 28K) only like memory of system of GSK-928 numerical control, because this uses memory adequately,be a when when making treatment technology, must consider main factor. To make full use of memory, radial plan taking a knife can be adopted when rough machining (1a) seeing a picture. Take a knife as a result of radial can generate a lot of interpolation data circularly for many times, because this and axial take knife look,Bikeming shows economic memory space, can increase the interpolation check the number of finish machining thereby, raise interpolation precision. The treatment plan that finish machining adopts edge curve axial to walk along interpolation of knife, circular arc (1b) seeing a picture. Of 3 machine program generate after building model of maths of circular arc interpolation, make treatment text file with C language. Define Fp of finger of a file above all, found file of a text with Fp, its working status setting is keep kind, dictate NC to with interpolation data keeps treatment file with NC code format with Fprintf() function next, the block form that writes circular arc interpolation if: Fprintf(Fp " N%d G%d X%2.



2f " , n, aotu, x, y, r) , among them variable N, Aotu, X, Y, R represents direction of block date, circular arc, X to be mixed to coordinate to coordinate, Z respectively radius of interpolation round mark. The computation of interpolation data and interpolation condition are controlled by statement of loop of C language For. Order flow is shown 2 times like the graph. Graph 4 machine program make 2 programs flow chart the applied basis of software is asked by treatment workpiece blueprint, input bus curve function and dimension parameter source program, after undertaking the function chooses applied, can realize the following application operation. The animation imitate that machines a process designed imitate of process of a treatment to emulate in emulation program with indication subprogram. After parameter of the bus equation that inputs workpiece, dimension chooses imitate to emulate mode of operation, run this subprogram, can give the whole process of treatment with animation form imitate. This process and be identical of photograph of effective treatment state, can show the actual figure after workpiece is machined, make operate personnel the validity of machine program of can rapid, intuitionistic test and verify, also can serve as the referenced basis that chooses cutting tool and treatment parameter. Cutting treatment chooses applied way to be operated for cutting, the coordinate of point of a knife that machines software to be able to make thick, precision work and the data that change a knife, use communication software to compile the system generated treatment data to dispatch system of lathe numerical control, classics optics machines origin and knife date, knife to slant to knife, setting after the convention such as the value is operated, can move in the operation on face plate of machine tool numerical control, undertake cutting is machined. The workpiece such as the supersonic luffing rod that application should process software to machine bus to be a variety of complex form such as double music function, index function on lathe of GSK-928 numerical control, all obtained favorable result. The bowstring dah such as this literary grace in order to divides 5 epilogue curve, regard interpolation circle as the method such as radius with average curvature radius, raised interpolation accuracy and the adaptability to different curve, wove corresponding machine program makes software. Exceed the order of systematic memory capacity to interpolation data capacity, can processing the order turning point cent to be a certain number of small order, use section to send by order, the method that section machines is solved. This software has stronger versatility, the workpiece that is the curve that be not a circle to bus is being machined on lathe of ordinary numerical control especially applicable, suit small lot treatment and workpiece generatrix type and dimension to change to machine a circumstance often very much. CNC Milling