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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.
181

Vřeteník a naklápěcí hlava frézovacího multifunkčního obráběcího centra s vodorovnou osou vřetena / Headstock and tilting head of a milling multi-purpose machining center with a horizontal spindle axis

Vazovan, Ľubomír January 2019 (has links)
The thesis contains of draft, calculations, CAD model and drawing documentation of the moltifunctional machining center with horizontal axis of spindle. This thesis is one of the four parts with which connection ensue the machine-tool. In the first part of my work, there is a constructional draft of the headstock which will enable milling, turning and drilling. In the introduction of this part is headstock research which is solving the most important parts of the headstock of machine . Consequently, technical calculations are acoomplished. Based on these calculations, a specific constructional draft of the headstock is crafted. In the next part of my work, I do research in the area of removable paring milling heads. After this part, there are technical calculations and the specific constructional draft. In the entire work, there is emphasis put on simplicity and functionality.
182

Modernizace řízení frézky FNG / The modernization of control system of milling machine FNG

Holas, Jiří January 2021 (has links)
This thesis deals with a proposal modernisation of control and electroinstalation of the milling machine FNG 32. The thesis is divided into several sections: The first section is dedicated to the research of the milling machine and the description of its current condition. The second section deals with possible options of retrofitting and with the components.The third section includes the technical and economical evaluation and the selection of the solution. In the next section, the selected components are described and an electronic documentation of the machine has been created in EPLAN. In the last section, a proposal of control of the milling machine has been created with the help of the TwinCAT development environment provided by Beckhoff company.
183

Optimalizace procesu montáže / Assembly process optimization

Dudarev, Ivan January 2009 (has links)
This diploma thesis deals with the optimization of the assembly process using the problem solving of optimal combination of parts of the machine tool to meet customer requirements. The aim to solve this task is creation applications for using scientific methods of research and methods of system analysis. The proposed solution is designed for the conditions of TOS KUŘIM - OS, a.s. The basis of the research is the method of system analysis as a basic method for effective solutions to improve the production activities, processes and systems.
184

Model profilu povrchu obrobku obrobeného válcovou obvodovou frézou / Model of surface profile after milling operation with plain milling cutter

Horváth, Ľudovít January 2014 (has links)
In the teoretical part of the master´s thesis, the master´s thesis deals with milling and surface profile describing. In the practical part, the master´s thesis deal with model of surface profile after milling operation with plain milling cetter. For evalution were used data obtained from the computer model of the surface profil and data obtained from measuring the actual surface profil, which was created by machining the material mills with a diameter of 45 mm.
185

Aplikace víceosového frézování na obrábění tvarové součásti / Application of the multi-axis milling of a shaped part

Klíma, Jiří January 2015 (has links)
This diploma thesis focuses on the design and production technology of making pattern and core box by milling. The theoretical part summarizes the issue of production models, CAD / CAM technology and milling technology. The practical part is elaborates engineering design of machined parts focused on the specific requirements for application in the foundry. For designing of milling technology was used CAM system. This milling technology was programmed and optimized. Parts are finally produced on 3-axis milling machine. In the end there is technical-economic evaluation of production and discussion of results.
186

Konstrukční návrh uzlu obráběcího stroje firmy Trimill / Design of subassemblies Trimill machine

Šrámek, Ondřej January 2016 (has links)
The aim of this thesis is design of automatic system for the exchange of milling heads. The diploma thesis was awarded in cooperation with company TRIMILL, a.s. The first part is devoted to a brief analysis of the problems of automation and includes a survey of the current market system of automatic exchange of milling head competing manufacturers. The second part deals with the choice of possible options exchange itself milling heads, the choice of propulsion, guidance etc. Afterwards there is an engineering design of chosen system, the engineering of leading and driving systems, safety features such as detection heads, sensors moving parts of the system and covers the entire system , then analysis of carrier system and covers are made .
187

ALGORITHM FOR STAIRCASE MACHINING OF NON-CONVEX POLYGONAL POCKETS WITH ISLANDS

RAMASWAMI, HEMANT January 2002 (has links)
No description available.
188

Stability of Pharmaceutical Cocrystal During Milling: A Case Study of 1:1 Caffeine-Glutaric Acid

Chow, P.S., Lau, G., Ng, W.K., Vangala, Venu R. 2017 June 1927 (has links)
Yes / Despite the rising interest in pharmaceutical cocrystals in the past decade, there is a lack of research in the solid processing of cocrystals downstream to crystallization. Mechanical stress induced by unit operations such as milling could affect the integrity of the material. The purpose of this study is to investigate the effect of milling on pharmaceutical cocrystal and compare the performance of ball mill and jet mill, using caffeine-glutaric acid (1:1) cocrystal as the model compound. Our results show that ball milling induced polymorphic transformation from the stable Form II to the metastable Form I; whereas Form II remained intact after jet milling. Jet milling was found to be effective in reducing particle size but ball milling was unable to reduce the particle beyond certain limit even with increasing milling intensity. Heating effect during ball milling was proposed as a possible explanation for the difference in the performance of the two types of mill. The local increase in temperature beyond the polymorphic transformation temperature may lead to the conversion from stable to metastable form. At longer ball milling duration, the local temperature could exceed the melting point of Form I, leading to surface melting and subsequent recrystallization of Form I from the melt and agglomeration of the crystals. The findings in this study have broader implications on the selection of mill and interpretation of milling results for not only pharmaceutical cocrystals but pharmaceutical compounds in general.
189

Návrh malé modelářské CNC frézky s pevným stolem / Design of small hobby CNC milling machine with fixed table

Hanzal, Jiří January 2020 (has links)
The topic of this work is the design of a small model CNC milling machine with a fixed table for machining wood, plastic, or light alloys (Al, Zn, etc.). It also includes a calculation report and drawing documentation of selected nodes. The beginning of this work consists of an introduction to the issue of milling machines, their distribution and subsequent market analysis. Subsequently, the input parameters are designed on the basis of market analysis and in the last part there is a calculation report, the design of the milling machine itself and a short economic evaluation.
190

Uma contribuição ao fresamento frontal de superficies irregulares de ferro fundido cinzento / A contribution to the face milling of irregular grey cast iron surface

Ferrer, Jorge Antonio Giles 31 July 2006 (has links)
Orientador: Anselmo Eduardo Diniz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-07T19:18:36Z (GMT). No. of bitstreams: 1 Ferrer_JorgeAntonioGiles_D.pdf: 4540427 bytes, checksum: 047f6383d5c609fa0233000c16e0843b (MD5) Previous issue date: 2006 / Resumo: A maior parte dos estudos sobre o processo de fresamento frontal aborda a usinagem de superfícies planas sem descontinuidades, o que na prática dificilmente acontece. Normalmente existem superfícies interrompidas com furos, superfícies estreitas que são usinadas com fresas de diâmetro grande, devido a uma pequena porção de largura maior, superfícies com rebaixos de 90o, o que faz com que todas as outras superfícies tenham que ser usinadas com uma fresa com este ângulo de posição, etc. Este trabalho pretende abordar alguns problemas gerados pelo fresamento de superfícies como as citadas. Assim, os ensaios deste trabalho foram realizados em peças de ferro fundido do meio produtivo (carcaça de compressor do sistema de freio de ônibus), que contém 3 superfícies a serem fresadas com características diferentes umas das outras. No fresamento de desbaste utilizou-se ferramenta de metal duro e cerâmica e analisou-se a influência da velocidade de corte e sentido de usinagem (concordante e discordante) sobre a vida da ferramenta, a produtividade do processo e a potência de corte. No processo de acabamento analisou-se também a influência do desgaste sobre a rugosidade da peça, especialmente usando pastilha alisadora. As principais conclusões deste trabalho foram: a) em operações de superfícies com rebaixo de 90o, em que o corte discordante se inicia com espessura de corte igual a zero, o corte concordante teve melhor desempenho em termos de desgaste da ferramenta; b) superfícies estreitas que são fresadas com fresas de diâmetro grande, devido à existência de uma pequena porção de largura maior, e que não possuem rebaixos para serem usinados, apresentaram melhor desempenho em termos de desgaste de ferramenta quando usinadas no sentido discordante; c) estas superfícies tem maior desgaste quanto maior o número de descontinuidades que possuir; d) no acabamento é possível substituir o processo de desbaste e acabamento por um único passe usando uma pastilha alisadora no jogo de pastilhas de cerâmica / Abstract: Most of the works about face milling are carried out on uninterrupted flat surfaces, which, in industrial practice, rarely occur. Usually what occur are interrupted surfaces with holes, narrow surfaces which are milled with large diameter cutters, due to a small portion of the surface with larger width, surfaces with corners of 90o, which makes mandatory the use of a 90o cutter, etc. This work deals with some problems generated by the milling of surfaces like those. So, the experiments of this work were carried out in parts of gray cast iron used in industrial production (block of compressor of a bus brake system), which contain three surfaces to be milled, with different features. In the rough milling tests, carbide and ceramic tools were used and the input variables were cutting speed and cutting direction (up and down milling). Their influences on tool lives, process productivity and cutting power were analyzed. In the finish milling tests, besides these parameters, workpiece surface roughness was also analyzed. The main conclusions of this work were: a) in the milling of surfaces with 900 corners, in which the up milling initiates with chip thickness equal to zero in each cutting edge, the down milling presented better performance in terms of tool wear; b) narrow surfaces which are milled with large diameter cutter, due to the fact that they present a small portion with larger width and which do not have corners to be machined, presented better performance in terms of tool wear when milled using up milling; c) the higher the number of interruptions of these kind of surfaces, the larger is the tool wear; d) in finish milling it is possible to replace rough and finish pass by just one cutter pass using wiper inserts / Doutorado / Engenharia de Fabricação / Doutor em Engenharia Mecânica

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