Thesis (DBA(DoctorateofBusinessAdministration))--University of South Australia, 2002.

Made available in DSpace on 2015-05-08T14:59:31Z (GMT). No. of bitstreams: 1 parte1.pdf: 1887121 bytes, checksum: 87cf54641c539882362cc0f679d7c951 (MD5) Previous issue date: 2011-04-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Machine tools play a key role in modern industrial production; therefore the technological development of machine tool industry has grown over the past decades. High Speed Machining (HSM) is widely used for machining complex and free form surfaces with high geometrical and dimensional accuracy. The spindle is one of the main items of a machine tool. Thus, it becomes necessary to know the influence levels of the main internal sources of heat in a machine tool. These sources basically derive from: transmission of electric engines; friction in drives and gear boxes; machining process (cutting, chip, workpiece); friction in bearings and guides. The dimensional and geometric accuracy of machined parts depends mainly on the performance of the spindle. To admit the idea of a holistic model, and then propose a possible optimization for a high-accuracy machining it is necessary to study and investigate the mechanical and thermal behaviour of the spindle. For that reason, this paper presents an analysis, based on the finite element method, of the mechanical and thermal displacements, as well as a determination of the critical speed of the spindle of the machine tool at high cutting speed. / As máquinas-ferramenta desempenham um papel fundamental nas produções industriais modernas, com isso o avanço tecnológico das indústrias das máquinas-ferramenta vem crescendo ao longo das últimas décadas. A usinagem com Alta Velocidade de corte HSM é largamente utilizada para usinagem de superfícies complexas e de forma livre com alta exatidão geométrica e dimensional. O eixo-árvore é um dos principais elementos de uma máquina-ferramenta. Então, se torna necessário conhecer o grau de influências das principais fontes internas de calor numa máquina-ferramenta. Estas provêm basicamente: Das transmissões dos motores elétricos; Dos atritos nos acionamentos e caixas de engrenagens; Do processo de usinagem (ação de corte, cavacos, peça); Dos atritos nos mancais e guias. A exatidão dimensional e geométrica das peças usinadas dependem principalmente da performance do eixo-árvore. Para que seja admitida a idéia de um modelo holístico, e então, propor uma possível otimização para uma usinagem de alta exatidão é necessário o estudo e a investigação do comportamento mecânico e térmico do eixo-árvore. Por isso, neste trabalho é apresentada a análise, baseada no método dos elementos finitos dos deslocamentos mecânicos e térmicos, bem como, a determinação da velocidade crítica do eixo-árvore da máquina-ferramenta em alta velocidade de corte (HSM).

Developments in cutting tools, coolants, drives, controls, tool changers, pallet changers and the philosophy of machine tool design have made ground breaking changes in machine tools and machining processes. Modern Machining Centres have been developed to perform several operations on several faces of a workpiece in a single setup. On the other hand industry requires high value added components, which have many quality critical features to be manufactured in an outsourcing environment as opposed to the traditional in-house manufacture. The success of this manufacture critically depends on matching the advanced features of the machine tools to the complexity of the component. This project has developed a methodology to represent the features of a machine tool in the form of an alphanumeric string and the features of the component in another string. The strings are then matched to choose the most suitable and economical Machine Tool for the component’s manufacture. Literature identified that block structure is the way to answer the question ‘how to systematically describe the layout of such a machining centre’. Incomplete attempts to describe a block structure as alphanumeric strings were also presented in the literature. Survey on sales literature from several machine tool suppliers was investigated to systematically identify the features need by the user for the choice of a machine tool. Combining these, a new alphanumeric string was developed to represent machine tools. Using these strings as one of the ‘key’s for sorting a database of machine tools was developed. A supporting database of machine tools was also developed. Survey on machining on the other hand identified, that machining features can be used as a basis for planning the machining of a component. It analysed various features and feature sets proposed and provided and their recognition in CAD models. Though a vast number of features were described only two sets were complete sets. The project was started with one of them, (the other was carrying too many unwanted details for the task of this project) machining features supported by ‘Expert Machinist’ software. But when it became unavailable a ‘Feature set’ along those lines were defined and used in the generation of an alphanumeric string to represent the work. Comparing the two strings led the choice of suitable machines from the database. The methodology is implemented as a bolt on software incorporated within Pro/Engineer software where one can model any given component using cut features (mimicking machining operation) and produce a list of machine tools having features for the machining of that component. This will enable outsourcing companies to identify those Precision Engineers who have the machine tools with the matching apabilities. Supporting software and databases were developed using Access Database, Visual Basic and C with Pro/TOOLKIT functions. The resulting software suite was tested on several case studies and found to be effective.

No description available.

This thesis deals with the development of graphical symbols on the control panels of machine tools made by Czech factories TOS from the years 1947–1990. The aim is description genesis graphics controllers and communicators of machine tools and their inclusion in the context of the development of graphic design. As well as determine the influence of design in area of operational graphics. This area has not yet been subjected to closer examination and in terms of consistency of the historical aspects of the Czech graphic is benefit to the future.

This work is focused on the software compensation of the geometric and volumetric errors. In the thesis there are descripted the measuring instruments suitable for measuring geometric and volumetric errors of the machine tool. In addition, there are described control systems and selected software compensations currently used in the machine tools. In the experimental part of the thesis there is briefly described the machining machine where the experiment was performed. Detailed procedures for using the used measuring instruments are also described. The aim of this thesis is to determine the influence of the size of the compensated volume on the geometric and volumetric precision of the machine tool.

The aim of the diploma thesis is to describe influences of selected production technologies on geometrical and dimensional accuracy of workpieces. Specific technologies - turning, milling and grinding and the machines on which these technologies will be implemented - a vertical lathe, a portal milling machine and a center grinder are described in this thesis. Additionally a procedure is created for adding geometric errors to a tri-axial machine tool to describe the entire working area of the machine in terms of errors. Subsequently an analysis of each geometric error is created for each machine and their influence on the resulting workpiece is determined.

This thesis deals with the development of graphical symbols on the control panels of machine tools made by Czech factories TOS from the years 1947–1990. The aim is description genesis graphics controllers and communicators of machine tools and their inclusion in the context of the development of graphic design. As well as determine the influence of design in area of operational graphics. This area has not yet been subjected to closer examination and in terms of consistency of the historical aspects of the Czech graphic is benefit to the future.

The topic of this work is the design of a vertical lathe with a table diameter of 2,500 mm. Part of the work is the analysis of current products in order to solve their shortcomings. The result is an innovative design focused on user-friendly operation and progressive shaping. At the same time, the designed machine fulfils all technical, ergonomic and aesthetic requirements.

The aim of the Master´s thesis is to design a chain tool magazine for a heavy duty machining centre for the non-rotational parts production. The Master’s thesis is ordered by TOS KURIM - OS, a.s. Company. The first part contains the analysis of the solved problems with the overview on the automatic tool changers, and the next part of the thesis deals with the proposal of options. Design of the chosen solution of the chain tool magazine is made in the next step, including sizing of the main parts. The 3D model of the chain tool magazine and drawings are included.