Of parameter of the craft when cutting tool of face of circumgyrate of CNC Machining special type detect automatically build a model

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Summary: To ensure the edge appearance of cutting tool of face of circumgyrate of special type of CNC Machining hard alloy is mixed width of 0 first flank, need pair of emery wheel photographs to wait for relevant craft parameter to undertake detecting to the position of workpiece. Those who put forward concerned craft parameter is automatic detect the method that build a model, think to apply this method to be able to raise the treatment precision of workpiece significantly. Cutting tool of face of circumgyrate of special type of hard alloy of 1 foreword whole is a kind of cutting tool that the plane is made and mould treatment middling uses, because its edge profile is complex, machine very hard with average mechanical tool grinding machine. As the occurrence of grinding machine of CNC5 axis tool, common circumgyrate face cutting tool can use a machine tool the slick campaign between 5 axes is made easily come out. In the numerical control finish machining of the mould, a few more commonly used also ball head dummy and columnar ball head are compound model cutting tool of face of special type circumgyrate regards finish machining as milling cutter. Be machined to make sure the cutting performance with good cutting tool is mixed the precision of the mould, ask to the geometrical dimension of cutting tool of face of special type circumgyrate and angle right now particularly strict. Accordingly, have document from cutting character proceed with, the knife that elaborated the horn before controlling cutting tool of face of special type circumgyrate actively on CNC tool grinding machine and helix angle orbit computation principle, set out from the grinding principle that assures edge appearance and width of 0 first flank, had firm demand to the position of workpiece to photograph of the emery wheel when CNC Machining. But when using grinding machine of homebred CNC tool to undertake machining, on one hand, because general armrest moves machine to detect,the fixed position of workpiece installs measure, detect efficiency is inferior, detect quality assures hard; On the other hand, the actual installation parameter of emery wheel also has change (the change of actual cone angle and diameter when turning like the emery wheel that causes by installation precision, the emery wheel that cause is placed by end when emery wheel is rotational the) such as the change of position of actual end panel and ply, can make emery wheel photograph produces change to affect the treatment quality of cutting tool thereby to the position of workpiece. For this, the author carries element of integrated consideration above, when building cutting tool of face of circumgyrate of a kind of CNC Machining of relevant craft parameter detect automatically model. If model of 2 edge maths and the grinding principle of 0 first flank width pursue 1 is shown, set workpiece coordinate department to be Ow-XwYwZw, p is the random on helix edge curve a bit, the equation of global where a thing can be put to best use of cutting tool of face of circumgyrate of general particular kind is as follows: In Xp=L+x(t)yp=r(t)sinqzp=r(t)cosq(1) type, q nods the corner variable that winds axes string for the random on edge, t is ginseng variable, l is the installation length of workpiece; The appearance of circumgyrate face and edge appearance are decided by function R(t) , X(t) . Graph 2 emery wheel machine graph of 1 helix edge sketch map of cutting tool of face of special type circumgyrate pursues 2 in edge 1 with edge 2 it is edge of two photographs adjacent, the appearance of two edge is identical, just turned in circumferential direction an angle Qz. Q is edge 2 on a bit more aleatoric, the point curve equation of 2 is edge in Xq=L+x(tq)yq=r(tq)sin(q+qz)zq=r(tq)cos(q+qz)(2) type, q=2p/zz, zz is the amount of tooth; Tq and T sense are same. The every tooth chamfer of cutting tool of face of circumgyrate of hard alloy special type is to use double taper normally model or emery wheel of odd taper diamond of grinding figuration. It is with grinding of odd taper emery wheel exemple (2) seeing a picture: The 1 P that go up orders the big circle of emery wheel and where a thing can be put to best use tangent, grinding gives edge face of the 1 knife before reaching; At the same time the cone of emery wheel should with edge the 2 Q that go up are nodded tangent, treatment gives edge of 2 hind knife face. Specific knife the method that seek solution already had the introduction in a few document, this not give uncecessary details. What need points out is, method of this kind of grinding is right emery wheel and be asked by the relative position of treatment cutting tool very strict, otherwise, can make wear the size of cutting tool first flank that give differ or on the circumgyrate face that edge is not asking. Accordingly, of research emery wheel and buy of counterpoint of cutting tool photograph detect automatically have very important sense. Pursue grinding machine of tool of linkage of axis of 3 vertical CNC5 of 3 craft parameter detect the XYZAC5 axis that model attempt shows grinding machine of tool of vertical CNC5 axis 3 times is a model (include X, Y, Z3 mobile axis and A, C rotates twice axis. Wheelhead box is OK direction of edge Y axis is fore-and-aft translation of fluctuation of direction of axis of Z of translation, edge, workpiece is OK translation of direction of edge X axis, wind oneself axes string roll and circumgyrate is made move on XY plane. The installation on the machine tool has sensor of a displacement spherical measure a head, when measuring a head to contact the face that be measured to produce displacement, it will issue signal to the system, the system will be self-recording the coordinate place that head center measures when beginning to contact. Because machine chooses emery wheel to have dimension and appearance error, mounting error exists in emery wheel installation, wheelhead rotor also exists at workpiece rotor relatively positional public errand, so the dynamic and integrated error of emery wheel makes design or the emery wheel after demarcate is met relative to the geometrical element at line of work axle center produce change, need undertakes detecting correctly to concerned craft parameter, in order to raise the precision of CNC Machining. What emery wheel cone angle, diameter and emery wheel measure head position to wait relatively discuss to detect respectively below method. The spends emery wheel with Shuang Zhui certainly cone angle of horn of emery wheel taper detects for exemple: Installation of emery wheel of will double taper makes turn on wheelhead when motion, because make mounting error of sum of errors make real position produced the emery wheel in motion to change, plus emery wheel swing, make actual cone angle produced emery wheel to change lesserly. To decide its are actual cone angle, on workbench place tries grind (4) seeing a picture. When undertaking metrical to double taper emery wheel, assume emery wheel double cone angle is B1, B2 respectively, use emery wheel first on the right side of cone along test specimen of grinding of around of X axis direction, reoccupy measures a head to measure test specimen to be ground two coordinate value that gets measuring head center (X1, y1) and (X2, y2) , criterion the cone angle B1 on the right side of emery wheel pursues for B1=tan-1(y1-y2)x1-x2(3) the measurement of cone angle of 4 emery wheel pursues of diameter of 5 emery wheel manage together certainly attainable also B2. For convenient control and operation, try grind dimension is special given. Of the emery wheel diameter that the basis chooses and cone angle different, it is OK also to try position of the emery wheel when grinding automatic computation is given. If choose emery wheel is spent for Chan Zhui model (dish form or bowl form) , measure cone a side only can (the another transverse plane of emery wheel often is not accurate plane, answer to ask to whether measure) certainly according to the precision of the product. If the graph is shown 5 times,emery wheel diameter is decided really, the two sides of test specimen of grinding of two positions after making emery wheel advanced, the distance with emery wheel mobile center is X; Reoccupy measures a two sides that measures test specimen, the space that sets shift of the center that measure a head is X. Criterion D of emery wheel diameter is D=x-xc+2rc(4) type in: Rc -- emery wheel of motion of the radius that measure a head and measure a head to be in Y to relative position is in certainly graph 3 in, emery wheel big circle is sectional (or main aspects face) rather the node of rotor heart line picks the reference point that is emery wheel, the reference point that measures a head is globose center. As a result of the error that make and assembles, the static state on direction of machine tool Y and dynamic value can have emery wheel reference point petty difference, and what in making, ask is the emery wheel below trends big circle is sectional (or main aspects face) the exact position on the machine tool; In addition, the workpiece installation in the every time on the machine tool the position also won't identical, need detects beforehand these parameter, feedback gives machine tool numerical control the system, change into emery wheel again the position of rest of opposite workpiece. Graph 6 showed the center that measure a head and reference point of double taper emery wheel are in the relative position of Y axis direction. The coordinate place that head reference point measures to go up in Y axis direction when setting Ys to be test specimen of emery wheel grinding (this coordinate value is OK) is given in the system, yc is the coordinate that head reference point measures to go up in Y axis when measuring to be worth (measuring a head to just contacted the face that be measured when subsequent unripe movements, this coordinate is worth control system below meeting record and show on screen come) . When test specimen of the grinding on Y direction, get the coordinate position Ys1 of emery wheel reference point and Ys2(want to make sure the coordinate in axis of the Z when two place grinding is worth equal) be when grinding of two side cone; Measure head check to check a two side to be ground when the face, the coordinate value of axis of the X when the coordinate position Yc1 that gets measuring head reference point and Yc2(should assure to be measured in two place, Z axis parts equal) . The distance Y that measures head reference point and emery wheel reference point on Y direction is Y=yc2-yc1-(ys2-ys2)tanb1tanb1+tanb2(5) type in, b1, b2 sees pattern (4) . Graph 6 emery wheel and measure a head to be in Y to relative position is in the machine tool, line of workpiece circumgyrate axes is in Y to position of rest also can be measured, its and type (5) connection, can decide emery wheel reference point is opposite the initiative position at line of work axle center. Those who need a specification is: Changing every time after emery wheel, must undertake emery wheel parameter afresh detect and the reference point that measure a head and emery wheel reference point are in Y way is opposite of the position detect. Of workpiece installation length detect in the graph 3 in, the X axis of the machine tool and coincide of line of work axle center, origin of workpiece coordinate department and origin of department of machine tool coordinate all choose the node in end panel blocking claw and line of work axle center to go up. As a result of type (1) , type (2) draw fast edge curve and installation length L are concerned, the length that so workpiece extends when the fixed position that hold clip plays the effect knife dot and whole knife the computation of orbit. The initiative installation length of set of hypothesis machine tool is Lb, sensor measures gotten error to be, length of actual installation is L=Lb ± (in 6) type, "+ " to grow, "- " to shorten (should undertake those who install length detect to every workpiece) . Those who pass above craft parameter detect, in knife of the emery wheel that seek solution when orbit, need only type (3) , type (4) and type (the computation of 6) feedbacks beforehand as a result in answering a system, go carrying out can. Graph of the code of 7 numerical control of grinding machine of numerical control tool that contain craft parameter to detect generate 4 knives of orbit and treatment campaign parameter after amending what considering workpiece to install diameter of length, emery wheel and cone angle to correct a problem, gotten knife the computation of orbit is the pose that emery wheel fastens at workpiece coordinate relatively as a result, must generate through postposition processing ability agree with the numerical control code that the machine tool moves; In the meantime, still need to use formula (the emery wheel in 6) and measure a head to be in Y to the measures a result to amend a machine tool Y of relative position to athletic parameter. Through such postposition processing, can get comparative the numerical control code of accurate machine tool motion. Contain the code of numerical control of grinding machine of numerical control tool that craft parameter detects generate a process to see a picture 7. Choose Leinishao (the LP2 sensor of RENISHAW) company and globose measure a head to undertake applied test and verify actually, the proof can ensure of parameter of the craft that be measured detect precision ≤ 2µm. 5 epilogue are when cutting tool of face of circumgyrate of CNC Machining special type, what the craft parameter such as the initiative and relative position of the installation length of the dynamic geometry parameter that place of grinding machine of numerical control tool uses emery wheel, workpiece and emery wheel and workpiece can put forward through the article is automatic detect the method undertakes detect and be correctioned conveniently, this is practical to raising the treatment precision of cutting tool of face of circumgyrate of CNC Machining special type to provide. CNC Milling