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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Pasivní kompenzace teplotních deformací u obráběcího stroje / Passive compensation of a thermal deformation for a machine tool

Šabart, Adam January 2017 (has links)
This master thesis deals with passive compensation of a thermal deformation for a binder of portal machining center. The problem is solved by computational modeling with finite element method using ANSYS Workbench software. Afterwards mathematical optimization (also using ANSYS Workbench software) is used for finding binder parameters in order to reduce thermal deformation and its weight. The output is two new versions of binder which are compared to the original configuration.
112

Zpracování dat z měření na obráběcích strojích / Data processing from measurement on machine tools

Pokorný, Zdeněk January 2018 (has links)
The Master’s thesis deals with the precision of machine tools, especially with the three-axis vertical milling machine. It is structurally divided into a theoretical and practical part. While the theoretical part focuses on problems of geometric errors and measuring devices, the practical one is devoted to the machine tool being tested. In this case, the data processing and the proposed statistical analysis are essential, and at the end of the thesis another possible way of developing the data processing is outlined.
113

Analýza rizik provozovaného CNC soustruhu SPM16 / Risk analysis of selected types of operated machine tools

Bernatík, Michal January 2019 (has links)
The thesis summarizes the legislative requirements for the operation of machines in the Czech Republic and the European Union. This thesis deals in detail with the analysis of technical standards related to machining tools, followed by the risk analysis of a specific machining tool operated in laboratories of the Faculty of Mechanical Engineering of the Brno University of Technology. The result of the thesis is the processing of identified risks and compliance with legislative requirements for the operation of the machining tool.
114

NC otočný stůl s lineární osou / NC rotary table with linear axis

Axmann, Patrik January 2020 (has links)
This diploma thesis deals with the construction of an NC rotary table with a linear axis. The first part is devoted to the analysis of the current state of science and technology in the problem, the use of various drives, mechanisms for torque transmission, linear feed lines, measuring and an overview of tables from various manufacturers. Furthermore, the work is devoted to the creation of 4 variants of construction, then the selection of the best variant and technical calculations. At the end, the work deals with a detailed description of the machine.
115

Konstrukční návrh otočného stolu s nosností 65 000 kilogramů / Design of rotary table with maximal load capacity 65 000 kg

Bezděk, Petr January 2021 (has links)
The diploma thesis deals with the design of a rotary table for machining large non-rotary workpieces up to a maximum weight of 65 000 kg. The aim of the work is to analyze and evaluate the current state of knowledge in the field of rotary tables, to create a table design according to the assignment and its 3D model with part of the drawing documentation. The theoretical part of the work searches for solutions used in the construction of rotary tables in the category of table according to the assignment. The information obtained is further used in the design of rotary table solution variants. By evaluating the weight of the required properties and their degree of fulfillment, a variant of the design solution of the table is selected, which is then designed. The individual design steps are described and explained in the text part of the work accompanied by pictures and calculations. The result of the process is a structural design of the mechanical part of the rotary table with a 3D model and partially processed drawing documentation. The contribution of the work is the summarization of relevant information for the design of rotary tables, the processed procedure of solving the design of the table and the modeled design of the rotary table. These outputs can be further treated as documentation for the production of the designed table, the development of the rotary table design to deeper details or technical development in this area.
116

Návrh a optimalizace tělesa vřeteníku pro obráběcí stroj / Design and optimization of a headstock for machine tools

Lekeš, Petr January 2021 (has links)
This diploma thesis deals with the design and optimization of a headstock for machine tool. Thesis was focused to comparison of several types of slide-ways and linear guides of headstock, considering their static and dynamic rigidity. An overview in the field of machine tools, their static and dynamic properties, use materials and design of headstocks, considering types of guideways, types of guideways drives and types of drives of spindle was made. Among the other main goals is included design of several types of guideway of headstock for horizontal machine tool, elaboration of computational models and evaluation of results.
117

Návrh progresivní technologie výroby tělesa šoupátka / Advanced technology project of valve body

Štábl, Martin January 2011 (has links)
This diploma work is dealing with the progressive production technology proposal of the valve body type S43 components. This is the high-pressure valve for the classical power supply. Here in the work is described the structural design of the valves, the material of the valve body and its machinability. Following an analysis of the existing production technology is the new production technology proposal for this part. All is designed with regards to the business possibilities of the Armaturka Vranová Lhota company. In conclusion of the work is presented the technical economic evaluation of both the existing and the proposed manufacturing technology.
118

Výpočtová analýza hybridního litino-kompozitového smykadla obráběcího centra TM 2000 / Computational analysis of the steel-composite carrier of the machining center TM 2000

Zbožínek, Martin January 2011 (has links)
The main objective of the work was to perform a computational analysis of the hybrid (steel-composite) carrier and compare the results with the original metal carrier. Static analysis, modal analysis and frequency response were solved. Computation was performed for three different relative positions of the carrier. Static stiffness, natural frequencies and dynamic compliance have been calculated. The results were verified by an experiment performed on a scaled-down model of the carrier. Modern software products, namely MSC Patran, MD Nastran, Matlab and ProENGINEER, were used for the calculation.
119

Nouvelle méthode de génération de gammes de fabrication prenant en compte des paramètres économiques et environnementaux / New generation method of manufacturing ranges taking into account economic and environmental parameters

Ben Jdidia, Anoire 04 July 2019 (has links)
Dans l’industrie manufacturière, la consommation d’énergie électrique est considérée comme l'un des problèmes majeurs qui est malheureusement liée systématiquement à l'émission de gaz contenant du dioxyde de carbone et amenant à l’effet de serre. Des études sur l’estimation de l’énergie électrique consommée par les machines outils sont développées par des chercheurs au cours des dernières décennie pour proposer des modèles d’estimation de cette énergie. Ces modèles sont soit empiriques soit théoriques et se limitent à tenir compte du comportement dynamique du système de coupe lors des opérations d’usinage. La contribution fondamentale de cette thèse de doctorat est la caractérisation du comportement non linéaire des efforts de coupe et du système de guidage lors de l’estimation de l’énergie consommée par une machine outil. La modélisation repose sur la détermination de l’effort de coupe et de l’effort des roulements qui sont variables en fonction du temps et qui sont déduites de l’écriture de l’équation de mouvement du système (broche ou machine-outil)discrétisé en éléments finis en utilisant la méthode de Newark couplée avec l’algorithme de Newton Raphson. Ces efforts de coupe et de roulements sont utilisés pour calculer la puissance puis l’énergie consommée par la table d’avance, la broche et par conséquent la machine outil. Afin de valider notre approche, la puissance et l’énergie obtenues à partir du modèle développé sont comparées avec la puissance et l’énergie obtenues avec un dispositif expérimental. Une étude paramétrique est réalisée pour mettre l’accent sur l’impact de la variation des paramètres de coupe sur la valeur de la puissance et de l’énergie consommées. On introduit par la suite des défauts d’usure et de montage au niveau des roulements et nous présentons leurs impacts sur le comportement énergétique de la machine. Une attention particulière a également été consacrée à développer un modèle d’optimisation des mouvement d’une machine outil globale minimisant à la fois l’énergie consommée, le temps de production, le coût et la rugosité de surface en respectant les consignes technologiques. / In manufacturing, the electrical energy consumption is considered as one of the major problems which are systematically related to the gas emission containing carbon dioxide and leading to the greenhouse effect. Studies based on the estimation of the machine tools energy consumption become the interest of researchers in recent decades.As a result, different models for energy estimating are developed in order to minimize the quantity of consumed energy. These models are either empirical or theoretical and are limited to taking into account the dynamic behavior of the cutting system during machining operations. The fundamental contribution of this doctoral thesis is the characterization of the nonlinear behavior of cutting and rolling forces during estimating the consumed energy by a machine tool. The developed approach is based on the determination of the variable cutting forces and bearings forces which are function of time. These forces are deduced by solving the equation of motion based on finite element method using Newark's method coupled with Newton Raphson's algorithm. These forces are used to calculate the power then the consumed energy by the axis feed, the spindle and therefore the machine tool. In order to validate our approach, the power and energy obtained from the model developed are compared with the power and energy obtained with an experimental device. A parametric study is carried out to focus on the impact of the variation of the cutting parameters on the value of the consumed power and energy. An interest is given for different types of defect (innerring spalling, outer ring spalling, eccentricity and unbalance) in order to study their impact on the spindle consumed power during approach and cutting phases under different rotating conditions. Particular attention has also been devoted to develop a global model for optimizing machine too lmovements that minimizes the consumed energy, the production time, the cost and the surface roughness with respect of the technological constraints.
120

Trajectoires de numérisation adaptatives en contexte in-situ / Adaptive scanning strategies for on-machine part inspection

Phan, Nguyen Duy Minh 20 March 2019 (has links)
Dans le contexte d'inspection du procédé d'usinage, l'intégration des opérations de mesure au processus de fabrication permet de réaliser les actions correctives à appliquer aux opérations de fabrication et ainsi de diminuer le temps de cycle de fabrication. Nous nous sommes intéressés dans ces travaux à la réalisation de la mesure on-machine par capteur laser plan dans une MOCN 5 axes. La problématique liée à la mesure on-machine concerne la proposition d'une méthode de planification de trajectoires qui résulte d'un compromis entre le temps de mesure et la qualité des données acquises.Nous proposons dans un premier temps un format de description des paramètres de la trajectoire du capteur permettant d'intégrer l'orientation de la broche dans la machine. Comme la détermination de point de vue dans notre contexte est adoptée pour le capteur laser plan, les contraintes de visibilité et de qualité sont appliquées à la position de ligne laser sur la surface. Nous proposons de réaliser d'un simulateur de trajectoires de numérisation. Ce simulateur nous permet d'identifier les zones de la pièce correctement numérisées en termes des critères de visibilité et de qualité. Il permet à la fois de valider la trajectoire avant l'exécution de la numérisation sur le système physique et d'aider à la génération de trajectoire de numérisation.Pour contrôler le temps et la qualité de numérisation, une méthode de planification de la trajectoire de numérisation pour une structure 6 axes, ISOvScan, est proposée. Dans cette méthode, la zone de recouvrement entre deux passes consécutives est constante, l'orientation du capteur en chaque point piloté est gérée afin d'assurer la qualité de numérisation et de maximiser le taux de couverture du laser. La méthode repose sur l'utilisation de la transformation conforme au sens des moindres carrés (Least Squares Conformal Maps-LSCM) pour transformer la surface 3D en un espace 2D. Le calcul de la trajectoire de numérisation peut alors être effectué plus simplement dans cet espace 2D.Comme la cinématique de la machine-outil 5 axes ne permet pas d'appliquer directement la trajectoire 6 axes créée par ISOvScan, les méthodes pour générer une trajectoire du capteur laser adaptée à la machine-outil 5-axes sont proposées dans ces travaux. Une application de numérisation sur la machine-outil 5-axes est réalisé pour vérifier la validité de la trajectoire de numérisation 5 axes. / In the context of the inspection of the machining process, the integration of the measurement operations into the manufacturing process allows to realize the corrective actions applied to the manufacturing operations and thus to reduce the manufacturing cycle time. Our objective in this work is to realize an on-machine measurement (OMM) by laser plane sensor in a 5-axis machine-tool. The problem related to OMM concerns the proposition of a scan path planning method that results from a compromise between the measurement time and the quality of the data acquired.First of all, we propose a description format of the parameters of the sensor path allowing to integrate the orientation of the spindle in the machine. As the determination of view point in our context is adopted for the laser plane sensor, the visibility and quality constraints are applied to the digitizing laser line position on the surface. We propose to realize a simulator of digitizing path. This simulator allows us to identify correctly the areas of the digitized part in terms of the scanning visibility and quality. It allows to validate the scan path before executing the scan on the physical system and to help the scan path generation.To control the scan time and quality, a scan path planning method for a 6-axis structure, ISOvScan, is proposed. In this method, the overlap zone between two consecutive passes is constant, the orientation of the sensor at each driven point is managed in order to ensure the scanning quality and to maximize the coverage rate of the laser. The method relies on the use of the Least Squares Conformal Maps (LSCM) to transform the 3D surface into a 2D space. The calculation of the scan path can then be done more simply in this 2D space.Since the kinematics of the machine tool does not enable to directly apply the 6 axes scan path created by ISOvScan, the methods for generating a laser scan path adapted to 5-axis machine-tool are proposed in this work. An application on the 5-axis machine-tool is performed to validate this adapted scan path.

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