Computer modelling and tool constructing for layered ...

Referent Hasanagić Redžo, Nezirević Ekrem University of Bihać,Faculty of Technical Engineering, dr.Irfana Ljubijankića bb.77000 Bihać, Bosnia & Herzegovina

Computer modelling and tool constructing for layered wood modelling

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Zusammenfassung: In dieser Arbeit wird das Prozess der Modellierung und Design-Tools für die Gestatung von axialsymmetrischen Werkstücke aus Schichtholz Beigevorganges und gleichzeitig ein Verkleben mit der Erwärmung des hochfrequenten elektrichen Storm seschreibt. Bei der Modellierung und Design-Tools ist fortschrittliche EDV-Anlagen und CAD-Tools sowie verfügbare Datenbanken verwendet.Auf der Grundlage des ausgewählten Werkstücks und von nominalle Dimensionen führte die Berechnung von strukturellen Parametern aus,die die Grundlage für die parametriche Modellierung bilden,und dann Design-Tools, die dürch die Form und Dimension mit einer angemessenen steifigkeit,gemischte Form und Genauigkeit der Dimension des hergestellten Werkstücks versichert werden.Die benutzte Metoden der Definition der endgültigen Desing-Tools stellen ein akzeptables Model In der Lösung der Probleme vor,mit denen sich die Designern und Technikern in der Produktion konfrontieren. Schlüsselwörter: Modellierung Werkzeug, Werkstück, parametrische Modellierung, Design

SUMMARY: In this paper is described modelling process and tool constructing for modelling of axis simetrical work piece of layered wood by binding process and at the same time by glueing with heating of high frequency electrical current.There are used by tool modelling and constructing the advanced computer equipment and CAD system tools and actual data basis.On the ground of selected work piece and its nominal dimensio is made the count of counting parameters which makes the ground for parameter modelling as well as tools which form and dimensions with defined rigidity will provide wanted form and dimension precision of made work piece.The used methods define finished tool construction present accepted model in the soluting of these problems which meet constructors and technologins in the producing process. Key words: modelling tools, work piece, parameter modelling, constructing

Aпстрактна: Овој документ ја опишува моделирање и дизајн алатки за дизајн на axisymmetric делови во обработка направени од дрво слоевит свиткување процес и во исто време се држат до загревање на висока фреквенција електрична струја. Кога моделирање и дизајн алатки кои се користат напредни компјутерска опрема и CAD алатки, како и расположливите бази на информации. Врз основа на избраните работното парче и нејзината номинална димензии Пресметка на структурните параметри кои ја формираат основата за параметарски моделирање, а потоа и алатки за дизајн кои, од страна на обликот и димензиите да се обезбеди соодветна цврстина саканиот облик и димензија точноста на произведените работното парче. Методи кои се користат да се дефинира конечниот дизајн алатки претставуваат прифатлив модел за справување со овие проблеми со кои се соочуваат дизајнери и технолози во процесот на производство. Клучни зборови: моделирање алатка, парче, параметарски моделирање, дизајн SAŽETAK: U ovom radu opisan je proces modeliranja i konstruiranja alata za oblikovanje osnosimetričnih obradaka od uslojenog drveta, postupkom savijanja i istovremenog ljepljenja uz zagrijavanje visokofrekventnom električnom strujom. Pri modeliranju i konstruiranju alata korištena je napredna računarska oprema i alati CAD sistema kao i raspoložive baze podataka. Na temelju odabranog obratka i njegovih nominalnih dimenzija izvršen je proračun konstruktivnih parametara koji čine osnovu za parametarsko modeliranje,zatim i konstruiranje alata koji će po svom obliku i dimenzijama uz odgovarajuću krutost obezbjediti željeni oblik i tačnost dimenzija izrađenog obratka. Korištene metode definiranja konačne konstrukcije alata predstavljaju prihvatljiv model u rješavanju ovakvih problema sa kojima se susreću konstruktori i tehnolozi u procesu proizvodnje. Ključne riječi: alat za oblikovanje, obradak, parametarsko modeliranje, konstruiranje

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1. INTRODUCTION Furniture production is based on technological process which is true and forward defined by producing process of some product, semi-product or product parts. The input raw material for some product change its form to get finished product or semi-product that is further processed. Furniture production is integrated process consisting of producing plan, producing program definition, ground and helping material providing, grying, cutting out, mechanical processing,part composing, surface processing, montage, product packing, and its external and internal transport. In the modern producing process, bound details made of layered wood often present key factor of contruction hardness, estitacal look and secessfull furniture export into the market. Therfore in the worlth among with development of peeled veneer. By intensive proceesing is developed work piece modelling process of layered wood from which is made furniture details of various finished forms and dimensions.There is dominant technik u technology work piece process development by high frequency electric current heating. In this paper is presented one of possible processing way of axis simetrical work piece of layered wood by binding process and at the same time by glueing with heating of high frequency electrical current for which is modelled and constructed modelling tool helping advanced computer tehniques and technoloy.

2. MODELLING AND CONSTRUCTION OF MODELLING TOOL 2.1. Construction process „Construction process is complex, technical, theoretical, experimental, information and intellectual process that stays in complex social and technological surrounding.“ [2]. Each construction process can be divided into small parts (phases, process parts, operation actions) which make the process structure. [4]. In the first process part of product construction, it is accented constructor creativity and ability to apply his knowledge in the soluting technical problems using standards, solution varites, catalogues of similar products and so on to optimize that solution with material, tecknological and economy limitations. In the second part there are necessary defined knowledges of construction process rules and technical drawing. The data processing is made by the sheme, figure 2.1.

Figure 2.1. The data processing in the construction process [8] Among constructor's own knowledge and information amount, the important factor is successful task making. The significant sources accepted by computer tehnique are data

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basis stored by computer into big computer systems. It is known that bigger producing systems in the world are developed on the knowledge bsis of expirienced constructors.. 2.2. Work piece choice and tool parameter account To model and construct modelling toolfor layered wood forming, it is necessary to know work pice parameters, its application and estetical look. For actual exampel it is selected the axis simetrical work piece of layered wood with brutto dimensions: total thickness: H  16,5mm , widness b  500mm , length : d  645mm , height ho  161mm and nominal semi-radius of cycle curve of rn  255mm . The total model of work piece look in 2D and 3D is presented by figures 2.2. and 2.3.

Figure 2.2. 2D graphical presentation of work piece with brutto dimensions

Figure 2.3. The 3D total model obratka with brutto dimensions The construction ground makes sheets of peeled beech veneer: thichness of 1,5 mm; II/III class; in the amount of 10 arts with parallel setting threads and one sheet of cutting beech veneer in the middle to achieve construction balance, u količini od deset komada; sa paralelno postavljenim vlakancima i jedan list sječenog bukovog furnira postavljen u sredini, zbog postizanja ravnoteže konstrukcije, thichness of 0,5 mm, II/III class, perpendicular setting threads in according to thread positions of other sheets. 2.3. The account of construction semi-radius of matrix and patrix On the ground of the most important and known work piece parameters there can be accounted the semi-radius of matrix cycle curve (rm) and patrix (rp), that are smaller than nominal that are computed by expression [1,3], n

rk  (1 

I 1

I

n

)rn

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Forwardly is needed to compute the inertion moment In and I for each single sheet in the construction „K“, and then the total inertion moments of work piece and on the ground [3] as well as the parameter values from 2.2., following that:

rk  rp  253mm , according to rm  rk  H  253  16,5  269,5mm . 2.4. Work piece model and modelling tool concepted by CAD tehnology CAD (Computer Aidid Design) is technoloy that uses computer systems as aid to create, change and optimize construction. The most important task that CAD needs to make is design gemetry as well as cocstructing because model look is ground for further activities in the producing process. On the ground of work piece form and dimension there will be used parameter modelling based on 3D CAD system for ground tool model defining presented as result by figure 2.4. The modelling process is made often in the three phases: model defining, model analyse and result use.

Figure 2.4. The ground model of binding tool and by it gotten work piece On the ground of work piece model and ground forming tool model (Figure 2.4) it can be made tool model from two parts (matrix and patrix made of combination of wood-metal) (figures 2.5. and 2.6), which sreve for form making of axis simetrical work piece.

Figure 2.5. 3D total tool model

Figure 2.6. 3D tool model -„demontaged“ 5

2.5. Graphical tool and work piece presentation Such modelled tool and work piece cen be before graphical presentation, tested helping metod of finished elements (MKE), simulating forming process at the computer applying adequate softwares.If the results show some disadvenatges , the constructor could take out them during the constructing process as the cheapest variety. If the tool shows satisfied hardness and doesn't demand corrections and if the work piece shows needed quality and dimension pricision, it could beginn graphical construction presentation. Tool construction drawings,2D graphical presentation, will draw hlpimg computer using standard elements from actual data basis. Along with technical drawings, it is possible to make other technical documentation and so finish the first phase of process. After that it follows tool performance, application in the production following its behaviour to improve itself.

3.CONCLUSION Constructing aided by computer, especially 3D model performance and preciously graphical presentation offer multiplied adventages because 3D models make easy post computer process supported by producing parts helping virtual model sets to present the total producing system from 3D models to make classical 2 D technical drawings that are composed by dimensions, tables,processings and enable form remembering as form oflibrary accordin to replaying of data basis. CAD syste application in this constructing process take more advantages in the aim of rationalization and achieving better results with optimization of technical solutions of product construction in defined surroundings to transform idea into a project by meeting of work cretivity, ability of fast and simple availability to recently constructions and data technical documentation, quick and easy creation of bids and possible extension of the CIM.

4. LITERATURE [1] [2] [3] [4] [5] [6]

Skakić D., Krdžović A., dipl.ing., „Finalna prerada drveta“ , ŠF, Beograd, 2002. Repčić N., „CAD metode- konstruiranje podržano računarima“, MF, Sarajevo, 1996. Skopal B., „Tehnološke naprave u finalnoj mehaničkoj obradi drveta“, Sarajevo, 1979. Hubka V., „Teorie der Konstruktionsprozesse“, Springer, 1976. Gologranac F., „Preoblikovanje“, Fakultet strojarstva, Ljubljana, 1991. Repčić N., Efendić M., „Auto CAD 2000-Primjena računara u konstruisanju“, Mašinski fakultet , Sarajevo, 2001. [7] Šunjić G., Maruš P., „Auto CAD 3D modeliranje“, Mostar. 2004. [8] Hubka V., Eder W.E., „Engineering Design-General Procedural Model of Engineering Design, Edition HEURISTA, Zűrich, 1992.

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