New-style point design reachs circumgyrate cutting tool fictitious production main force is current model

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Summary: In the light of tradition of circumgyrate cutting tool point design method is in CNC Machining of 2 axes linkage the problem that encounter, put forward circumgyrate cutting tool new-style point devises a method, derivation corresponding design and fictitious production main force is current model, gave out representative application example. Cutting tool of 1 foreword circumgyrate is to machine complex curved surface (be like all sorts of moulds face and free curved surface) main cutting tool. The design of circumgyrate cutting tool and CNC Machining are made take seriously extensively what be concerned an expert domestic and internationally. Basically use 3 axes, four-axle or machine tool of numerical control of 5 axes linkage domestic and internationally to machine circumgyrate cutting tool at present, finished cost is accordingly higher. To reduce the finished cost of circumgyrate cutting tool, the author answers Harbin the requirement of works of the 2nd tool, with Taiwan scholar collaboration studies, gave out 2 axes linkage machines circumgyrate cutting tool plan and relevant treatment model, and trial-produce treatment of 2 axes linkage uses cone milling cutter. The author succeeds in Taiwan paper of college doctor's degree " the research that differential geometry makes a model in CNC Machining and cutting cutting tool " in the cooperative research of the research of author Wu Changzun and as successful as Taiwan university and institute of far east technology, when discovery is machining the circumgyrate cutting tool that designs by traditional method, although use 2 axes linkage to machine plan comparing to use 3, program of four-axle linkage treatment can save a large number of installation cost, but it is difficult to be put in what need to alternate groove of grinding cutting tool uses dip angle of instantaneous of emery wheel axis however on craft, need to add when axis of executive instantaneous emery wheel locates more complex clamping apparatus, cause in sheet, manufacturing cost will raise significantly when small lot is produced. The cutting tool point that the article tells convention of beyond the mark analyse designs the problem that encounters in CNC Machining of 2 axes linkage, put forward to settle the way of this one difficult problem, gave out cutting tool design and fictitious production trunk model. If be in cutting tool point circumgyrate face equation to write down,2 traditional point design the issue in CNC Machining of 2 axes linkage for R={g(u) , f(u)cosv, f(u)sinv}(1) is become point curve and warp (Dv=0) becomes the Y that decide part, with axes (1, 0, when 0) becomes the Y that decide part, and it is when point curve when waiting for pitch curve, the differential equation with point contented curve is ordinal for Dv1=tany(f2+g2)½du1f(2)dv2=(g2tan2y-f2)½du2f(3)dv3=g Du3b(4) type (2) ～ (the model of 3 kinds of designs that 4) is traditional point namely. Type (in 4) , b is the helix parameter that waits for pitch point, when pitch is T, b=T(/2p) . When groove of cutting tool of circumgyrate of CNC Machining of 2 axes linkage, the circumgyrate angular velocity that takes circumgyrate cutting tool is Dv/dt=w, criterion point assumes office the circumgyrate linear velocity of a bit is Vj=fw(5) right now, 3 kinds of correspondence designs at traditional point are formulary (2) ～ (the emery wheel axes that the axial feed speed of 4) parts to if grind,make cutting tool point and groove for Vx1=g(u1)du1dv1=wfgcotydv1dt(f2+g2) ½(6)vx2=wfg(g2tan2y-f2)½(7)vx3=bw(8) and X axis become F part, have F=arctanvxvj(9) type (6) ～ (8) ordinal generation enters type (9) , can get F1=arctangcoty(f2+g2)½(10)f2=arctang(g2tan2y-f2)½(11)f3=arctanbf(12) by type (10) ～ (12) is knowable, the included angle Fi(i=1 of emery wheel axis and rotor X ～ 3) is along with the change of parameter U change, namely the change as U, the included angle that needs to change emery wheel axis and rotor X ceaselessly just can realize traditional point to design, when undertaking CNC Machining accordingly, need to add add clamping apparatus to realize the fixed position of emery wheel axis. Apparent, this to sheet, the manufacturing certainly will of small lot cutting tool raises manufacturing cost greatly. The definition that principle of design of 3 new-style point and design model design according to 3 kinds of traditional point, want point to submit corkscrewed yarn form inside specific circumgyrate area only, can regard cutting tool of a kind of circumgyrate as point. To settle traditional point the design is in CNC Machining of 2 axes linkage the F horn that encounter changes problem, but first set F is worth to decide (F=f0) , again converse beg a differential equation that ought to satisfy. Press this train of thought, according to Vx=gdudv=wgdudvdtdv(13) and type (5) , but by type (9) reachs if give initiative condition U=u0,Tanf0=gdufdv(14) has Du=ftanf0dvg(15) or Dv=gcotf0duf(16) namely from time to tome V=v0, can adopt pair of form (16) integral begs a V=v(u) , take the place of again type (1) , can seek a circumgyrate range (the new-style point on 1) . 4 circumgyrate cutting tool is fictitious current model considers production main force other document (Ren Bingyin, Tang Yuyong, Chen Chaoguang is written " The Generalgeometrical Models Of The Design And 2-axis NC Machining Of Ahelical End-mill With Constant Pitch " ) already bat around optimize form of design groove cut, basis according to the element such as material groove cut form, and new-style point design and the corresponding model that traditional point designs are same, the article is accordingly right this no longer give uncecessary details. Because new-style point designs the differential that designs correspondence with traditional point,equation differs, because this needs new derivation, in order to devise the opposite campaign of emery wheel and circumgyrate cutting tool. Above all, the circumgyrate angular velocity of circumgyrate cutting tool is W, corresponding circumgyrate linear velocity is changeless, still press type (5) computation; Next, because axial and radial feed speed and Du/dv are relevant, because this produced change. According to type (not difficult derivation gives 5) milling cutter of head of ball of form of Vx=gwduwfcotf0=vjcotf0dv(17)vg=-rfvjcotf0Rg(18) circular arc is schematic (in 18) , what R has helix point for circumgyrate knife is the biggest outside round radius, r is right now core thick radius. Basis " The Generalgeometrical Models Of The Design And 2-axis NC Machining Of Ahelical End-mill With Constant Pitch " , as a result of,Sg of instantaneous radial feed should satisfy Sg=rf(u)R-r(19) of the following condition Vg=dsg/dt, can get form accordingly (18) . Use afore-mentioned opposite sports models at face of emery wheel outline, get emery wheel outline the curved surface including sth resembling a net of face a group of things with common features -- realization groove curved surface, seek a realization groove and circumgyrate range again (of 1) cross a line -- realization point curve; Undertake corresponding aftertreatment as a result according to fictitious computation next. The trunk model of follow-up part and " The Generalgeometrical Models Of The Design And 2-axis NC Machining Of Ahelical End-mill With Constant Pitch " identical, earnings result also close, the article no longer enumerate of one by one. The ball head milling cutter that to in an attempt to of 5 application example shows the circular arc that take protruding 1 times is exemple, the correspondence on face of convex arc circumgyrate at type (1) has {f1=R-R1+R1cosu1g1=R1sinu1(20) type in, r1 is convex arc radius, its era enters type (16) has Dv1=coty0R1cosu1du1R-R1+R1cosu1(21) to given initiative condition U1=0, v1=0, to going up type is integral, v1=cotf0(u1-arctan(2R-R1-R2)½tan U1/2)R(2RR1-R2)½(22) is in the joint of face of convex arc circumgyrate and ball head face, when U1=u2=a, corresponding V2=v1 | U1=a, because this can face answering computation according to the ball,integral and successive condition is narrated before formulary {f2=Rcosu2g2=(R1-R)sina+Rsinu2(23) seeks a Dv2=cotf0du2(24) ground to going up type is integral, have V2=u2cotf0+cotf0(a-arctan(2R-R1-R2)½tana/2)R(2RR1-R2)½(25) type (23) ～ (in 25) , r is spherical radius. type (21) , (24) takes the place of respectively type (17) , (18) , the axial that can get correspondence and computation of radial feed speed are formulary. Length of 6 epilogue be confined to, the article introduced decisive trunk model only, and as identical as each bibliographical reference all be omitted with close part. With 3 kinds traditional point designs model photograph to compare, the means of new-style point design that 2 axes linkage machines difficult problem and offers to solve circumgyrate cutting tool has the writer clear advantage and project value, offerred handier and practical academic premise for milling cutter of circumgyrate of special type of CNC Machining of 2 axes linkage. In addition, the batch treatment of circumgyrate milling cutter still can adopt plan of blame CNC Machining (if use end panel cam and profiling) give implementation. Accordingly, the academic research that has development to this one task has main project to use value. CNC Milling