The design of the model that note model that is based on converse project and make

Summary: The design that uses converse project technology plastic jug pattern and in making, through using PIX-30 3 coordinate measuring instrument collects data, use UG software to undertake data processing, model rebuilds, mould design and automatic process designing, the fast design that implements the standard that note model thereby and make. Keyword: Converse project; UG; Note model model; Fast design; Fast production foreword is in the development process of plastic product, geometrical modelling technology already was used quite extensively. But as a result of a variety of reasons, the technical data that pattern company accepts from the manufacturer often is not the model of CAD, the objective pattern that constitutes by complex free curve curved surface however, if use traditional method to design production product, manufacturing cycle is long, cost is high, what cannot answer ten thousand changes in the twinkling of an eye is plastic taste the market, and converse project (Reverse Engineering) offerred advantage to solve this one difficult problem. Because this is converse,the project serves as a burgeoning course more and more pay close attention to and be taken seriously of people. Traditional design method is it is a foundation with the function, through plan design, sketch design and product are made, assemble, serve as ultimate goal in order to get product in kind, and converse engineering design is to be aimed at existing workpiece, especially complex irregular free curved surface, use 3D to digitlize a measuring instrument, accurate, apace measures an outline coordinate value, and compose builds curved surface, warp knitting collect, after revising, turn to system of average CAD ／ CAM, the three dimension word on will original objective or computer of video translate into turns a model, the NC that produces cutting tool by CAM again machines method and convey to CNC machine tool, the place that make needs a mould, perhaps make STL file, with fast and archetypal technology (RP) makes sample model. According to the three-dimensional digitlization model of sample, can revise mould aspect repeatedly, generate NC automatically machine program, raise a mould to manufacture efficiency greatly thereby, reduce a mould to make cost. Converse project technology is in our country, there is very wide application perspective in the industry that note model especially. At present the working flow of converse project is like the structural system of 1 converse project the graph is shown 1 times, basically divide composition by 3: Model of the digitlization of product objective appearance, CAD rebuilds, product or mould are made. The crucial technology of converse project is data is collected, of data processing and model rebuild. 1.

1 data collects data to gather the first pace that is converse project, its method affected data of the 2 dimension of objective, three-dimensional geometry correctly directly, affect the quality of rebuilding CAD hypostatic model, affect the quality of the product finally. 1.

Before 2 data processing are undertaking to a series of gotten data that nod the cloud CAD model rebuilds, filter of the transition that must have a pattern, noise is divided, flowing, right the processing such as compensation of exploration head radius. 1.

3 models rebuild will treated measure data to guide CAD system, compose of the curve that founds before the basis, curved surface builds the three-dimensional digitlization prototype of objective. The digitlization design of mould of 2 plastic jug and make 2.

The data of 1 jug prototype collects use PIX-30 scanning of 3 coordinate measuring instrument is measured, get nodding cloud data. Secure jug above all go up in scanning platform, adjust the scanning area of scanning probe, make scanning area as it happens includes the largest measure of jug. Undertake be metricaled automatically next, measure midpoint and dot span and scanning beam and scanning beam span all but free set. Measure data to be saved with STL format, after facilitating, with UG software is opened. Graph the 2 three-dimensional scanning that are jug sample nod cloud data. 2.

2 data processing put a way as a result of the measurement of 3 coordinate measuring instrument, the error tackles the impact of the element such as means and surroundings, the data nodding the cloud that makes be collected gets inevitably the pollution of noise, be in at the same time cave the area is sure meeting generation measures blind area, so, the edition must have to data before begging a model instead. Delete the check the number that does not need to occupy, filter noise, reduce bit of data number, in the change of curved surface slow place takes bit of thickness more few and far between, change to should take a place thick and fast for the most part relatively in curvature. To selecting bit of blind area, can use fill command to undertake repairing. Undertake going to primitive dot cloud above all a confusion of voices is flowing processing, the model whole smooth compliance after such repairing is attainable rise further. 2.

3 jug rebuild archetypally in UG system, curved surface is a kind of general term, piece body and hypostatic free surface can call curved surface. The mathematical property of UG curved surface is B curved surface, namely NURBS(is not batten of even and justifiable B) curved surface. B curved surface by a certain number of curved surface piece (fill piece) form, its parameter curve is multistage batten; Sheet fills a curved surface it is curved surface of Bei Sai Er, its parameter curve is odd paragraph of batten, curved surface of Er of shellfish a place of strategic importance is the special case of B curved surface. UG system has powerful curved surface to build modular function, when the design, construct first by the data that nod the cloud curve, construct by the curve again curved surface. Found free curve, curve of batten of main use Spline() command. Command of menu of Insert Curve Spline moves in UG, occurrence Spline dialog box. Perpendicular To Planes can be reached in Bypoles of the choice in the dialog box, Through Poi Nts, Fit 4 kinds of means found a curve. Can undertake controlling curvilinear rank in follow-up measure second with paragraph the analysis of number, curve shows, appoint slope and appoint the operation such as curvature. Nextpage popularly, to improve final curved surface quality, curvilinear appearance should achieve the following requirement: Even without change of sharp drop, curvature amount of reference point of on-line of flowing, music as far as possible little. Want to make sure curvilinear whole is characteristic at the same time, wait like concave and convex sex and smooth compliance. Using the curve that constructs beforehand to found curved surface as data-in is tectonic curved surface is main put a way. Main command is: Insert ／ Free From Feature child below menu establish a system through the curve (Through Curves) , establish a system through curvilinear reseau (Through Curve Mesh) , through the curve scanning establishs a system (Sweep) . Graph the models of 3 line draw a frame round that showed jug. Building a system is not the purpose that UG builds a model, ultimate goal is to should build hypostatic model. Suture can be passed in UG, fill substance of a body, clip, add thick the method such as a body creates entity. Graph 4 it is the jug prototype that finishs finally. 2.

The generates mould design flow of 4 moulds spare parts is normally: (1) product design (the three-dimensional model that establish three-dimensional model directly or guides) . (2) observation analyses the rake giving a model of hypostatic model and cent case. (Layout of antrum of the cent of 3) design mould face, model, inside insert, push rod, runner, refrigeration and electrode. (Model of substance of name of 4) initialization project, to load and unit. (5) unplugs modular way, shrinkage is mixed certainly shape mold insert. (6) repairs open face. (7) defines cent area. (8) joins standard mould bases, push rod, slide block, inside smoke core and inside insert. (9) design runner, flow path, cooling, electrode, establish antrum and kind stuff detailed account. (The CAM module that 10) uses UG is generated model core, model the NC of antrum machine program. The Injection Mold Tooling in using UG is designed (Mold Wizard) module, transfer into acquisition watering can is archetypal, the square that passes set Z axis to give way for the top, installing mould coordinate is, take model shrinkage is 1.

005, repass setting shapes mold insert, layout, repair, build minute of molded lines, establish cent range, the key that can design the model that note model quickly thereby -- if punch pursues be shown 5 times and if sunken model pursues show 6 times. 2.

Of program of NC of 5 moulds spare parts generate the mould part that will acquire to guide directly the CAM module of UG, choose different cutting tool and treatment way according to curved surface, set the parameter such as rotate speed of dosage of reasonable craft parameter, cutting, main shaft. Imitate copy affirms really without by accident hind, the aftertreatment that chooses machining center implement, the system makes NCI of milling fixed position and NC file automatically, carry out treatment through reticle and machine tool communication. The design that 3 conclusion use converse project technology the model that note model and in making, have the aid of is mixed at 3 coordinate measuring instrument UG software, collect through data, data processing, product builds program of design of model, mould, NC to generate and treatment. Can shorten greatly the design of the mould and production cycle, accelerate the development rate of the product, raise products plan and made precision, enhance the competitive ability of the enterprise. Design in the pattern with spare parts mixed appearance especially with in making, its advantage is more clear. Accordingly, the application of converse project, will conduce to the technical content that raises whole pattern, promote a mould the competition ability of the enterprise. CNC Milling