Change of consideration cutting tool moves the cutting process below to emulate build a model with cutting force

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In modern manufacturing industry, milling treatment is a kind of extensive and efficient treatment way, rise increasingly as what people asks to spare parts precision, the precision that undertakes to machining a process emulates the attention that got a lot of learned men, because the microcosmic movement in cutting is hard to show, so great majority forecasts a method is the mechanical and mechanical emulation model that builds based cutting strength, its parameter comes from more at the experiment, precision emulates medium mathematical model to include to cut model of force of model of trends of bits geometry model, system, cutting normally, among them difficulty depends on building mechanical emulation model. In using the process that cutting tool of much tine cutting has milling is machined, cutting tool change is moved make each tine rotates radius each are not identical, bring about not was out of shape the ply that cut bits produces change, cause the change of cutting load thereby, change of the load that cut bits can change force of force of average cutting force, the biggest cutting, the smallest cutting and instantaneous cutting force, cause cutting tool attaint, cutting tool to wear away and systematic trends changes, bring exterior error, lower cutting tool life. Main shaft deflection, cutting tool tilts, the grinding effect of cutting tool, cutting tool wears away, shed the bits concussion to cutting tool, and the change that the element such as systematic trends unbalance can cause cutting tool is moved. Among them before both to unify an element, have the appearance that exists generally. Moved scholars to make a large number of research to cutting tool change, diameter of dot of cutting of the cutting tool below the circumstance that Kline and Devor[1] elaborated change of consideration cutting tool to move, instantaneous was not out of shape cut bits ply the ply that cut bits, on average to reach cut cut a corner and did with the case that did not consider cutting tool change to move quite. K.

Y.

Lee [2] makes the same score low milling cutter to be in what the cutting tool change in machining a process moves parameter to determine to 4 tine formulated new method. Vre of Re-Lorph è of Edouard Rivi è [3] studied the new parameter that moves about change of cutting tool radial decides algorithm. Tony L.

Schmitz [the effect that 4] key discussed cutting tool change to move stability of error of pair of workpiece surface figuration, surface, treatment. SantoshRanganath [the research that 5] summarized forefathers to be moved to cutting tool change, effect of cutting tool grinding, cutting tool wears away in waiting for those who be not unified element to introduce cutting tool change to move a diameter to seek solution course, put forward new relevant data to collect method and parameter to determine a method. In addition, k.

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Desai [the cutting tool change that 6] studied curved surface treatment is medium uses an issue, built the process geometry model that change of consideration cutting tool uses. The article considered cutting tool change to use the important influence in machining a process, the cutting tool trochoid from inside treatment sets out, use numerical value to analyse a method to seek solution relevant parameter, gotten result and test result can good be identical. Change of movable mould of cutting tool change cutting tool is moved is to point to in machining a process, rotate by cutting tool the differs to distance of each cutting blade phenomenon that the center measures (graph 1) , traditional cutting tool change moved a model to include main shaft deflection and cutting tool to tilt. The cutter spindle that main shaft deflection points to to cutting tool secures end to be measured and rotate central existence deviation, rotate to be apart from ρ with the center by cutting tool center, and λ of horn of tooth fixed position (by random tooth is gotten recently) definition. Cutting tool tilts show cutter spindle is put in proper point of view with runner shaft coming back, by banking angle τ , and rotate definition of φ of central position horn. SantoshRanganath[5] effect of cutting tool grinding, cutting tool wears away etc was not unified element to introduce cutting tool change to use a model, through be not K of unified parameter δ (K states K ages) definition. Each parameter is decided by the experiment, the value that the cutting force value that traditional pattern measures through comparing and computation get undertakes comparative finding " Bestfit " value, this kind of method assumes cutting tool is tigidity, take no account of the blame such as effect of cutting tool grinding to unify an element, the research of this kind of method is the mechanical and mechanical model that includes cutting tool change to move mainly is not cutting tool change moves itself. Used Santosh Ranganath[5] when change of affirmatory cutting tool moves parameter " SimplexSearch Technique " , obtained favorable result. Cutting tool change moves a model to include the radius of cutting blade cutting when cutting tool change is moved, cutting tool change is moved cause not was out of shape the ply that cut bits changes, cut the change that cuts a corner and cutting tool change to use the machining error that cause. The cutting radius when change of 1 cutting tool is moved tilts as a result of cutting tool the value is very little, the impact that and can make its through setting referenced range right machines is the least change, and Kline and Devor[1] think cutting tool wears away to unify an element with the blame such as effect of cutting tool grinding lesser to the influence of treatment (0.

0025mm) and studying a lieutenant general its oversight, and main shaft deflection is right ultimate treatment result effect cannot be ignored, the article basically discusses the effect of main shaft deflection to treatment. I is located in to age below the condition that changes existence in cutting tool change, the cutting that Z axis coordinate is Z is small yuan cutting radius is: Among them, r is radius of cutting tool name, ρ is cutting tool center and rotate central distance, λ is horn of tooth fixed position, nt is number of cutting tool tine, z is tooth small yuan of coordinate on Z axis, ah is cutting tool helix angle. The ply cutting bits when change of 2 cutting tool uses presence (1) movable mould of change of traditional cutting tool. The influence reduce that orthodox cutting ply model uses cutting tool change changes every tine feed, express to be: Namely the every tine feed that I ages is equal to name the difference that every age feed adds radius of radius of this tine cutting and cutting of before one tooth, f(th, z) is name every tine feed, h(i, z) is not was out of shape cutting ply, horny θ (I, z) ages to be this positional horn. This model simplified cutting tool change uses a process, move in cutting tool change can get effectively when the photograph is lesser to every tine feed not was out of shape the ply that cut bits. Nextpage (2) movable mould of improvement cutting tool change. Pass the analysis of contrail of pair of cutting of true cutting tool, can get exacter cutting tool change uses a model. It is origin O with the cutting tool center when I=0, feed direction is X axis, machining exterior normal direction to build coordinate for Y axis is, in this coordinate department coordinate of cutting tool center is: Move when cutting tool change when the photograph is older to odd tine feed, tooth may cutting the leftover contrail that I+k ages, pursue for example 2 in 4 tine cutting tool machines orbit, because of the presence that cutting tool change uses, make the cutting radius of each tine differs, the tine in the graph the 1 leftover data that in A place purify the 3rd tine keeps, is not before purify one tine ages namely the leftover material of 2. Tine 4 in B place purify ages the leftover material of 3 is not before purify one tine age namely the 1 cutting mark that leave. Can use following methods to beg solution to not was out of shape from this the ply that cut bits. Hypothesis cutting dot is Q, criterion its coordinate is: Right now, by C of cutting tool center, and P, Q nods at 3 o'clock in all the line is attainable: Nextpage gets ply is cutting bits thereby: Because K is sealed, because this cannot be calculated directly,cutting tool was not out of shape the ply that cut bits, can make K=1, 2... , nt, calculate respectively cutting ply, the result that gets each value undertakes comparative, the least value is namely cut bits ply actually, if calculate,gotten the least value is negative, explain this tine did not participate in cutting, make should age the ply that cut bits is 0. If the graph is shown 4 times, the PQ1 in the graph, PQ2, PQ3 all cuts bits ply for what exist possibly, because PQ1 is the smallest, PQ1 is the ply that cut bits namely. 3 cutting tool are cut it is certainly into what cut a corner below the circumstance that takes no account of cutting tool change to move, because each age equality participates in cutting, cut cut a horn to be constant value, when cutting tool change uses presence, because each age cutting radius differs, can produce the phenomenon that the K before current tooth cutting ages, thereby cutting tool is cut cut a horn to be able to produce change. Cutting cut bit of part, cutting ply is 0 if the graph is shown 5 times, horn of position of corresponding cutting tool cuts a corner to be cut namely. Affirmatory method is as follows: (1) computation is in A1=- π / 2 or 3 π / the H1 of the ply that cut bits of 2 place, sure to lose. (2) computational A2= π / the H2 of the ply that cut bits of 2 place, h2 of judgement H1 · is like this value to be, explain this tine did not attend cutting. If its value is,lose, have: A.

Be in according to median theorem (- π / 2, π / 2) inside exist some a little bit to make the ply that cut bits is worth surely for 0, make this a little bit nod Pen to be cut. Pen can pass following methods to undertake deciding: Your A3= (A1 +a2) / 2, computational the place cuts bits ply H3, judge (H0 · H3) , be like H0 · H3=0, nod at this o'clock to be cut namely; < of H3 of the · that be like H0 0, make A2=a3, h2=h3; > of H3 of the · that be like H0 0, make A1=a3, h1=h3. Circulate this process, until (A1=a2) contented tolerance ε , en= (a1 + A2)/2 extraction θ enters horn to cut. B.

Be in with manage (- π / 2, 3 π / 2) inside also some a little bit makes the ply that cut bits is 0, take at this o'clock nod Pex to be cut. Press as above method, can find out likewise cut horny θ Ex. Change of 4 cutting tool moves the machining error below existence to be in treatment process, machining error results from trochoid of two-phase adjacent cutting tool intersects gains sharp point and shape exterior height is poor, if the graph is shown 5 times, to going against mill machining error generation is in at cutting a point, according to cut bit of computation: Model of force of cutting of model of Nextpage cutting force is the core content that treatment process physics emulates, the precision that its precision decided to physics is emulated, and cutting tool change is moved is the inevitable question in aging cutting tool is machined more, in using cutting tool change the model to introduce cutting force model consequently very necessary, cutting tool change moves the ply cutting bits in basically affecting mechanical model, cut cut a corner. Cutting force model basically has 2 kinds as follows: The first kind of model is based on microcosmic physics phenomenon, forecast the pattern that cuts bits and cutting strength, for example finite element law, this kind of model is comprised by a variety of complex material trends models, below most circumstance, to orthogonal cutting calculate capacity finite, because build a model to need to spend a large number of time to machining a process, so aborning is used lesser. The 2nd kind of model also is the model that is accepted extensively, to be based on mechanical and mechanical treatment the process simplifies model, axial of cutting tool edge is broken up to be a certain number of equidistant bridge is unit, what each unit suffers cutting force to be become independent to consider, the parameter that its defect depends on computational cutting force needing is not to originate material itself is characteristic, get through the experiment however. The article introduces the 2nd kind of model, following place are shown. The bridge that is Dz for Z, ply to some axial coordinate is unit, action at I the cutting force on cutting blade is dissoluble the force that goes up for 3 different way: Tangential force DFt(i, z) , radial load DFr(i, z) reachs axial force DFa(i, z) , because axial force affects not old friend to machining a process,the article considers only tangential reach radial load to have: Among them, kr, kt, ka expresses the cutting force parameter on respective direction respectively, its value can be reached by the experiment. H(i, z) is correspondence at this cutting small yuan instantaneous was not out of shape the ply that cut bits. Analyse computation to go to the lavatory, each force umbriferous to standard coordinate get inside the department: Will all Nt the cutting force addition that gets on tooth gets cutting tool is in the cutting force that gets right now: The article passes experiment test and verify the cutting force of will academic earning and measure earning cutting force to undertake comparative thereby the accuracy that change of cutting tool of test and verify uses a model, use a diameter to be 20mm, helix angle makes the same score bottom milling cutter to have the job for the 3 tine of 35 ° , collect cutting force data through Kistler9255 measuring instrument, cutting material is Al-2618. Experiment cent is 2 groups, if the watch is shown 1 times, among them ρ =3.

2 μ M, λ =48.

8 ° , the academic cutting force when graph 6(a) is moved to take no account of cutting tool change and experiment measure the comparison of gotten cutting power, below good position, cutting force curve shows regular change, have bigger difference with actual cutting force. Below the circumstance of the influence that uses pair of treatment in change of consideration cutting tool, the cutting tool change in orthodox model and article moved a model to undertake emulation imitate, its refer to graph 6(b) and graph 6(c) as a result. Can see 2 kinds of models as a result quite from emulation result and real cutting power can very good imitate is actual cutting process, and the change movable mould in the article more orthodox model approachs the numerical value that measures at the experiment more. Graph 6(d) used the cutting condition parameter of B group, got satisfactory emulation result likewise. The article built the last word to be based on treatment process the movable mould of cutting tool change of actual cutting contrail, to machining a process medium not was out of shape the ply that cut bits, cut cut a horn to wait undertook study, the model that offers the article through a series of experiments and the contrast that take no account of cutting tool change to move change of model, traditional cutting tool to moved a model to undertake cutting force forecasts a result, got satisfactory result. Change of the cutting tool in the article proving likewise below the condition that changes in cutting parameter finally moves a model to be able to forecast cutting process effectively. The emulation that can see pair of cutting strength through the experiment still is put in certain error, because existence cutting tool is returned to be out of shape in machining a process,that is, heat is out of shape, cutting tool wears away, cutting tool shakes wait for an element to meet produce an effect to machining a process, at the same time these elements also can affect cutting tool change to move, reduce the accuracy that forecast. Cutting tool change is moved is a complex process, also need with the compositive research of other precision influencing factor more thorough spread out. CNC Milling CNC Machining