1 foreword is in mould manufacturing industry, with high speed milling treatment replaces electric treatment to already made trend of a kind of development. The typical craft of mould antrum finish machining is: Semifinished product rough machining finish machining of heat treatment → of → semifinishing machining → (high speed or exceed) of high speed milling. In finish machining working procedure, often use small diameter to establish milling cutter to undertake below high rotate speed clear part and imperceptible structure are machined (small diameter cutting tool machines easy happening below low rotate speed collapse blade or rupture) . Because small diameter establishs milling cutter to suffer when force,be out of shape easily, bring about treatment precision to be short of break, because this establishs field of stress of force of milling cutter milling to small diameter,undertake finite yuan of analysis very be necessary. The geometrical relation that circumferential milling machines basic model is like force of milling of 2 instantaneous trends the graph is shown 1 times. Take no account of the advance gradually wear process of milling cutter here. Force of instantaneous trends milling is dissoluble for instantaneous DFri of circumferential milling force. I(is tangential force) with) of radial load of DFri(of instantaneous cutting perpendicular force, can express to be: In type, KS is tangential milling force coefficient; I) of ψ of T I (is instantaneous cutting ply (the function) that it is time; R is cutting tool radius; β is cutting tool helix angle; C is cutting force tangential the coefficient of proportionality with radial; ψ I is I the tine that a cutting nods horn, its computation formula is: ψ I= ψ + θ + (one 1)2 of I π / M, (M of ≤ of 1 ≤ I, o ≤ ψ " Ψ , among them: ψ is helix lag horn, θ is the angle that cutting tool has turned in Dt time, m is number of cutting tool tine, Ψ cuts corner for cutting tool, when axial cutting deepness is Ba, have: Graph the horn before the geometrical relation instantaneous that 1 circumferential milling machines cuts bits ply and knife to have effect is right of dynamic milling force the influence can express to be: Week mill treatment has different treatment kind (2) seeing a picture. When He Nixi machines suitable mill, the total cutting force of every cutting blade is: In type, the initiative lag horn that Ψ E and Ψ S are cutting blade and end lag part, can press the following computation of two kinds of methods: M after the cutting force of cutting blade is accumulated, the total cutting power that can get place of whole cutting tool to suffer is: Nextpage pursues the different kind that 2 circumferential milling machine 3 in establishing force of milling cutter milling to experiment in milling force, use Kistler(9257B) 3 measure amplifier of power instrument, charge to trends (5017B) and A/D changeover card measure condition of different when high speed cutting cutting (deepness of cutting speed, cutting and feed) the cutting force below, the working principle of system of milling force test sees a picture 3. The cutting strength that this experiment gains still can be in stress field is narrow yuan use at accepting force border condition certainly when the analysis. Graph principle of system of test of 3 milling force pursues the 4 substance that establish milling cutter build a model to make a principle according to milling cutter, the choice builds milling cutter model with the means of purify material. Milling cutter is central semmetry structure, the mill tooth number that the article studies is 3, the L/3 that chooses milling cutter so undertakes building a model, use a feature to command those who finish whole model to build next. Concrete move is as follows: (1) runs UG software, build a part " Mill " , click " build a model " → " columnar " , play piece build cylinder, the scale of the outline outside the cutter hub that finish. (2) is clicked " insert " → " curve " → " helix " , shoot a corkscrewed yarn dialog box, input parameter, click affirmatory, face of the knife before building the first corkscrewed yarn. Manage together, before the basis, hind knife face and end are mixed to face of the knife before scale of cut form parameter additionally 3 corkscrewed yarn that helix groove place needs. (3) is clicked " straight grain face " , individual choice measure (2) builds before knife face corkscrewed yarn and the corkscrewed yarn that helix groove needs, straight grain is facial in face of the knife before fashioning cutting tool respectively and helix groove cent. (4) is clicked " careless draw " , start of choice corkscrewed yarn is in columnar end panel to be careless draw plane, scale forms the round arc that helix groove place needs. Click " already swept sweep past " , choose the round arc that just built to be strung together for sectional line, measure (2 corkscrewed yarn that 2) builds are strung together for lead, click affirmatory, the scale of part of face of the circular arc in groove of the helix that finish. (5) chooses " the face is round " , respectively measure (3) , (the curved surface that 4) builds connects joint and be a curved surface, establish one plane and parallel of columnar end panel in the midpoint place of corkscrewed yarn next, with in front amalgamative curved surface cuts out this are planar, incorporate two curved surface for one curved surface. (6) chooses " cut out body " , with measure (the curved surface that 5) forms cuts out cylinder, form " Trimbodoy " feature, next annular array this feature, finish those who establish model of milling cutter substance to build. 5 those who establish field of milling cutter stress is finite yuan of analysis 5. 1 finite the substance that finish builds yuan of analysis model after the model, must undertake to hypostatic model reseau differentiates, impose border bound requirement next. Experiment by milling force: F=546N, f=532N, f=472N, can undertake on face of the knife before bringing to bear on its to establish milling cutter finite yuan of analysis, undertake the model is checked finally. 5.
2 finite yuan of analysis measure (1) is clicked " application " → " the structure is analysed " , enter finite yuan of analysis module; Click " solution " , play piece " environment " dialog box, the setting is finite yuan of analysis environment; Click " material attribute " , play piece " material " dialog box, choose cutting tool material and gift cutting tool body. (2) is clicked " 3D tetrahedral reseau " , appear three-dimensional reseau builder, click " automatic choice " can calculate automatically by the computer a more appropriate unit measure, choose cutting tool form, generate 3D reseau. (3) is clicked " attribute editor " , to needing to edit the combination of reseau face and curve undertake attribute is installed, editor density; Choice " update finite yuan of model " , update model reseau; Choose again " material attribute " , choose the reseau that has differentiated, make reseau is gifted the physical characteristic such as material; Click " load type " , add load for the model; Choose " tie type " , for finite yuan the model adds attrib border requirement. (4) chooses " finite yuan of model examination " , occurrence model checks a dialog box, setting examination type is " integrated " , click affirmatory; Click " solution calculates " , play piece " solution calculates " dialog box, click affirmatory, finite yuan the model begins to undertake an analysis, when occurrence analysis finishs a dialog box, click affirmatory can. 5.
3 examine result classics computer to assist solution to calculate with the aftertreatment, the three-dimensional stress field when can getting establishing milling cutter cutting distributings result. See by the result, the stress that establishs milling cutter basically distributings to reach the crucial point at the cantilever place of milling cutter. 6 epilogue used UG to build establish model of milling cutter substance, gave out according to result of cutting force test attrib border condition, in establish milling cutter finite yuan of to load on the model, use next finite contrary milling cutter is in yuan of analysis module the stress field in cutting process undertook analytic study. Cloud atlas showed the instantaneous stress field that establishs milling cutter to cut a person, cut pattern of change of the stress in reaching cutting, ji Jifeng of stress peak value is worth area, to optimize cutting dosage the relation between each parameter and milling force and high speed of small diameter cutting tool are machined complex model precision machines when antrum mould rise laid a foundation. CNC Milling
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