Analysis of character of condition of movement of pillar of vertical machining center and develop attack optimize

Of model of 1 pillar substance build pass slide block and guide screw and pillar to be linked together directly considering main shaft box, contrary column this one bearing for main shaft box regards its bigger concentration as quality, and be in working process, the slide block action that cutting force is box of main shaft of have the aid of arrives on two slideway of pillar, main shaft box is so contrary of column defy a turn, fight twist and the movement condition character such as natural frequency is having bigger effect. To assure follow-up analysis and the accuracy of the to load in optimizing a process and convenient sex, also build model of main shaft box along with all the others piece, undertake the analysis of force through main shaft box, make the circumstance getting power of pillar more accord with actual. Build modular efficiency to rise, use SolidWorks software builds model of pillar structure substance, next, use do not have between software seam connective advantage to guide directly melt into of Workbench change trains is finite yuan of model. When building three-dimensional and hypostatic model, to be helpful for sequel finite of yuan of analysis begin, considering a few small features the movement condition character to integral model is affected lesser, friend author undertook simplifying reasonably to feature of ministry of ministry branch bureau, take out is petty if the feature pours horn, round horn and whorl to wait. Simplify model of substance of rear column structure is shown 1 times like the graph. 1.

2 pillar are finite of yuan of model build a root to be analysed according to actual condition, main shaft box is located in pillar most on when carrying ultimate position, characteristic to the movement condition of pillar impact is the biggest, accordingly, box of choice main shaft is located in pillar most on operating mode of upright maximum position undertakes analysis and optimize have typical sense more. Pillar and main shaft box belong to cast, material chooses material of HT300; main shaft to be GCr15; line course and slide block material to choose QT600-3 character. If material attribute expresses 1 to show. Those who use Workbench is finite yuan of reseau that processing tool can install a few kinds to differ to the model differentiate means, but consider pillar structure is more complex, the method that reason uses automatic reseau to differentiate undertakes to its with tetrahedral the reseau that give priority to differentiates. Set parameter through debugging reseau repeatedly, generate 298 573 node, 189 861 is unit, among them reseau unit quality is 0.

Coefficient of 715 8, degree of bias is 0.

372 5, explain reseau quality achieved idealer result. Pillar structure is limited if yuan of model pursues 2 are shown. Character of condition of 2 pillar movement analyses 　 2.

The load that place of pillar of machining center of 1 load analysis gets has delivering through main shaft box, and in different treatment form and different treatment position fall, place of main shaft box gets cutting force form and bulk also is different. And means of machining center cutting includes mill commonly, auger, a variety of treatment such as boring and treatment whorl, reason needs to undertake dangerous operating mode analyse according to different treatment form. Be aimed at actual condition, choose Duan Xi, get the treatment form that cuts two kinds of typical operating mode to undertake load is analysed. 2.

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1 auger cut the load below operating mode to analyse machining center getting when cutting treatment operating mode auger cut torsion of feed force Ff and cutting can Mc press the following formula to undertake computational: ? Street? D is diameter of the oldest bit, mm; F turns for every feed, mm/r; CFf, ZFf, YFf cuts feed force coefficient and exponential; CMc, ZMc, YMc to be cutting torsion coefficient and exponential; KFf, KMc to be the correction coefficient of feed force and torsion respectively respectively to get respectively, usually, desirable KFf, KMc is 1. concerned parameter era enters type (1) , type (2) computation can be gotten: 2.

1.

Analysis of the load below operating mode of 2 end mill is according to this vertical machining center below milling operating mode commonly used circumstance, choose upright milling cutter, cutting tool material is hard alloy, workpiece material is carbolic steel, advocate can cutting force Fc press: of computation of following experience formula? Is X of  of  of Cuo tadpole  : ?  X = 0. Is Fy of force of 3Fc 　 fore-and-aft feed: ? Is Z of  of  of melon tadpole  : ?  Z = 0. In 5Fc 　 type: Ae is spent to be machined to express bizygomatic breadth, mm; Fz is every tine feed, mm/z; Ap is cutting deepness, mm; Z ages for milling cutter several; D are milling cutter diameter, mm; N is milling cutter rotate speed, r /min. Does will relevant parameter take the place of to you can get: into formulary computation? " ぶ of commonplace of outskirt of  naphthalene ⑹ goes value of mu of market of condyle of Han of ⒆ of field of bring a case to court summary Gao of You of low-lyingponding protruding た evil spirit carry on one's shoulder of download of operating mode of Duan Xi of? of rice huller of  of the Mao that treat soft-shelled turtle is more complex, and each also are compared to component of force big, contrary below the operating mode that carry mill column undertakes character is analysed changing a static state, can reflect performance of pillar movement condition in the round more. 2.

2 statics analysis is right below Workbench environment when the model imposes to load carry on one's shoulder and obligation, answer to undertake an analysis according to particular case, such ability ensure the dependability of computational earnings result. Because pillar is to pass the lathe bed of bolt and underside to have link, to its so combinative scale and face of pillar bolt aperture undertake displacement tie comes the combinative scale of box of main shaft of; of its border condition and pillar uses simulation Banded contacts unit type to undertake imitate. Pass to load of hypostatic to pillar model to analyse, beg solution to get its displacement and equivalent stress cloud atlas, if pursue,3 are shown. Analyse a result according to character of static state of graph 3a pillar knowable, the biggest deflection of pillar is 0.

087 277mm, appear in its coping. By this token, main shaft casing is located in pillar most on when carrying ultimate position operating mode, the deflection of pillar is lesser, static stiffness is enough, not big to machining the influence of precision. Show pillar equivalent from graph 3b place in light of stress cloud atlas, the greatest equivalent stress is 12.

352MPa, although consider the case that stress centers, according to theory of the 4th intensity, the greatest equivalent stress is far still the intensity limit 300MPa that is less than casting pig. From the point of pillar whole, its stiffness and intensity not only achieve structural demand, and still have certain abundant amount, show existing structure design tends conservative, show its adequately material allocation still can be improved further. 2.

Analysis of mode of 3 mode analysis is a substantial in analyse of structural motivation credit, in order to determines the natural frequency of hypostatic structure and corresponding vibration shape, the reasonable design that is a structure provides corresponding basis, prevent its to produce resonance in working process. Because the article cares the oscillatory character of pillar oneself only, do not have box of necessary consideration main shaft to wait when undertaking mode is analysed consequently. When the natural frequency of exterior drive and pillar is adjacent, easy cause resonance, its basically care when so mode is analysed low rank natural frequency. In the tie condition falls, before solving those who get pillar through begging 6 rank natural frequency and vibration shape, if analytic result expresses 2 to show. Before pillar 4 rank graph of mode vibration shape sees a picture 4. From the graph 4 in can see, 1 rank and 2 rank vibration shape characteristic basically is behaved in pillar on end happening around, or so shimmy, and 3 rank with 4 rank vibration shape feature is reflected respectively in the end on pillar two sidewall appear twist brace up be out of shape, around wall breath is oscillatory. Of pillar 1 rank natural frequency is 125.

03Hz, in considering the work, to its dependability reachs stability target the demand is higher, reason is small rank natural frequency still remains to rise. 2.

4 humorous answer minute of analyse humorous to answer an analysis is to analyse a structure to fight brace up function, it undertakes on the foundation that analyses in mode, contrary column undertakes humorous answers an analysis, can see its disturb the ability of next counteractive vibration in dynamic cutting force relatively intuitionisticly. In working process, the natural frequency that should prevent to suffer dynamic drive and pillar as far as possible is conterminous close, prevent the resonance of pillar effectively, increase the treatment precision of the machine tool and stability thereby. Integration analysis, limits of frequency of brief humorous force installs 625Hz of the ～ that it is 0, when interval is 25Hz surely, contrary column X, Y, Z3 direction answers displacement to have consideration, if the graph is shown 5 times,get a frequency character curve. From the graph 5 in X, Y, Z3 the curve can see a frequency character on direction, its frequency is in 125, 250 with 525Hz around when, amplitude is bigger, incidental resonance. Mode analysis result is knowable before union, analyse of humorous noisy part of one's job and mode analysis result roughly be identical, thereby the validity that confirm analyses. Develop of 3 pillar much target attacks optimize reach a structure to improve 　 3.

Develop of 1 much target attacks optimizing the principle that optimizes a design is to use compose to build optimize a model, use all sorts of optimizing method, ask through satisfying a design the iteration below the condition is calculated, get the extreme value of target function, win best design program. Have good movement condition character to make optimize a result, the target that reason will consider static stiffness, dynamic oscillatory frequency at the same time attacks as develop optimized catalogue mark function. Much target optimizes a problem to use linear to add the method that authority mixes normally, this kind of method has certain limitation, so the article applies eclectic program law to combine average frequency law to undertake handling to mark of many specific item, the associated develop that has movement condition character to the structure attacks optimize, can its maths model express to be: ? The opposite density embattle that ρ of ∈ street? is pillar construction unit ρ of; F() the weight; Q that combines ω of; of integrated target function to be flexibility target function for structural activity condition is castigatory factor, 2; M of Q ≥ is K for K of ω of; of gross of load operating mode the authority of operating mode is worth ρ of; Ck() it is K the flexibility; Ckmax of operating mode, Ckmin is K respectively the maximum of operating mode flexibility and Λ of; of the least value (ρ ) before be two rank. Because static stiffness and dynamic frequency are the target function of two mutual contradiction, weight allocation has differred big when make stiffness and frequency target function are achieved at the same time hard best. Before passing, the face analyses result and the heavy visual range that optimize a target to each to spend to pillar movement condition, attack in much target develop in optimized integrated target function, the authority cost that takes flexibility is 0.

4, the power worth of frequency is 0.

6, castigatory factor is 2. With type (3) attacks as much target develop optimize target function, draw materials makings reduces percentage for 30% , after passing 26 paces iteration, did not produce oscillation phenomenon, target function tends convergent. Curve of target function iteration is shown 6 times like the graph, develop attacks if the graph is shown 7 times,optimize density cloud atlas. 3.

The movement condition character that pillar faces before 2 structures improve tie analyses a result, but from the graph 7 develop attack optimized density cloud atlas sees, brunet area is bogus density is the material of 1, the data of these area shows the share that the proposal excises, and other the part that the material that is not brunet area is need reservation, this offerred corresponding train of thought for the improvement of pillar structure. Additional, attack from develop optimize a result knowable, the proposal moves the material appearance that eliminate is irregular, considering the actual condition in pillar design, production process, can not move all material that are brunet part entirely except, so the material of should brunet to pillar area undertakes be optimizinged reasonably. Be aimed at the actual feature of pillar structure, rectangle of instead of aperture of roundlet of former pillar lateral aperture; is at the back of its back with bottom reasonable decorate round hole; to improve its appropriately at the same time in-house muscle hardens compose reachs ply. If the graph is shown 8 times,optimize rear column model. Below identical operating mode, undertake to optimizing rear column statics analysis and mode are analysed. If the watch is shown 3 times,pillar optimizes the analytic result of around. From the watch 3 in can see, optimize rear column photograph to compare at optimizing before pillar, static stiffness rises somewhat, its quality decreases 3.

57% , 1 rank, 2 rank natural frequency increases respectively 7.

82% , 4.

79% . 4 epilogue are right the important bearing of vertical machining center when pillar undertakes study an analysis, make to make sure the accuracy of to load, convenient sex is mixed circumstance getting power more accord with actual, the article builds the hypostatic model of pillar and main shaft box along with all the others piece, to its below typical operating mode the structure undertakes character is analysed changing a static state. The associated develop that applies eclectic program law and average frequency law to build character of pillar movement condition attacks optimize mathematical model, use ANSYS software to undertake to its structure much target develop attacks optimize an analysis. Undertake through contrary column structure analysis and associated develop attack using static character optimize a design, can coach effectively the architect is reasonable layout its structure, can reduce pillar quality not only, still can raise its to use static property, it is research machining center thereby the movement condition character of other part and optimize a design to provide reference. CNC Milling CNC Machining