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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.
11

Konstrukce jednoúčelového frézovacího stroje / Design of single-purpose milling machine

Čunek, Jakub January 2013 (has links)
This thesis provides a brief introduction to the technology milling and analysis of various parts of milling machines. In addition, this thesis focuses on the design of a dedicated milling machine for machining functional areas of aluminum cast.
12

An Adaptive Control Algorithm for a CNC Milling Machine

Mailvaganam, Gajananda Nandakumar 04 1900 (has links)
<p> The purpose of this project was to develop an Adaptive Control Algorithm for a CNC milling machine. The milling machine is controlled by a 2100A Hewlett Packard mini-computer. The Adaptive Control Software has to operate in unison with an already available Numerical Control Software. Both these programmes are stored in the computer and the computer operates on them with the aid of the interrupt pulses received from the Time Base Generator located in the Controller.</p> <p> The Adaptive Control Software should be capable of optimising the milling process, that is enabling the milling machine to operate at the highest feed-rate without violating or overriding the maximum permissible values of the horizontal force and torque acting on the cutter. These maximum values of the force and torque are determined from the tool strength and capacities of the servo drives and spindle motor. Further, the machine should be able to arrive at the above feed-rate in the shortest possible time interval without causing cyclic variations in the feed-rate which could lead to an unstable system. The programme should be able to obtain ten samples of the parameters per revolution of the spindle. The feed-rate thus obtained (after comparing with the maximum and minimum feed-rates of the machine and making any corrections, if necessary) should be stored in a memory location accessible to the Numerical Control Programme. The instantaneous values of the force and torque are transmitted to the computer via the transducers attached on the spindle of the machine and the Analog-to-Digital Processor, therefore, the Adaptive Control Software will have to communicate with the Analog-to-Digital Processor in order to receive the values of the forces and torque. Thus the above mentioned requirements will have to be met by this piece of software. With this end in view, the following algorithm was developed.</p> <p> The algorithm consists of two portions, namely, the Data Reading Routine and the Policy Routine. The former accepts the two horizontal forces (which are phase shifted by 90°) and the torque acting on the cutter by communicating with the Analog-to-Digital Processor. However, all these three parameters are received through the same channel from the Analog-to-Digital Processor as such a method of identifying the variables was necessary. For this purpose, the Data Reading Routine consists of software capable of communicating with the Analog-to-Digital Processor at time intervals of 10 m.sec. and receiving the data in a digital form, decoding the input and ascertaining which input parameter was received. The Policy Routine has two modes of operation viz., the constraint and optimizing modes. This routine ascertains the critical error and arrives at the new feed-rate depending on the Policy used. After checking the value of this feed-rate with the maximum and minimum feed-rates available on the machine (and corrections made if necessary), the suitable value of this feed-rate is stored in a memory location accessible to the Numerical Control programme. This gives the general structure of the Adaptive Control Algorithm developed in this project.</p> / Thesis / Master of Engineering (MEngr)
13

Konstrukční návrh os frézky / Design of axis of milling machine

Hájek, Roman January 2017 (has links)
This master thesis is dealing with the design of the frame and working axis of the desktop milling machine. The theoretical part is in the form of a research of the construction of small machine tools. Practical part concerns the idea for a design of the working axis, as well as the design of the frame construction. Practical part also contains the selection of the main and most important components.
14

Návrh malé modelářské CNC frézky s pohyblivým stolem / Design of small modeling CNC milling machine with movable table

Havlíček, Ondřej January 2019 (has links)
This master thesis deals with the constructional design of small CNC milling machine with a sliding table. The first part of the work describes small CNC milling machines currently available on the market. Based on the result of the literature review, the small CNC milling machine was constructed with respect to the currently available trends, including sizing and drawing documentation of the machine.
15

Návrh hobby CNC frézky / Hobby CNC milling machine design

Buš, Martin January 2020 (has links)
This master thesis is focused on design of CNC hobby milling machine.In the first part of master thesis there are brief information about construction of CNC milling machines with varios types of milling machines available on market. After that, is made a selection of suitable machine componets for selected parameters. Futhermore, the masters thesis include a solutions of the component on all axes CNC milling machines.
16

Konstrukční návrh portálové CNC frézky / Design of gantry CNC milling machine

Ludva, Jan January 2016 (has links)
This master’s thesis deals with a design of a portal CNC milling machine. The thesis contains a description of milling machine’s single types, analysis of Czech and foreign market and analysis of basic milling machine’s groups. The work includes calculating of cutting forces and moments of a chosen tool, choice of spindle and design of axe’s drive systems. The thesis also includes 3D model of the chosen variant, it’s by a method of final elements and finally drawing documentation.
17

Konstrukční návrh portálové CNC frézky s posuvným stolem / Design of the gantry CNC milling machine with sliding table

Kolář, David January 2017 (has links)
This master’s thesis is focused on design of gantry CNC milling machine with sliding table. Thesis includes the review of components of this machines and comparsion of their options. Servo motors , ball screws and linear guides parameters are calculated. Also the suitable software and hardware for the machine control is chosen. Main parts of the machine were analysed using finite elements method. 3D model, drawings and documentation of machine build are included.
18

Konstrukce natáčivé frézovací hlavy / Design of turning milling head

Orság, Petr January 2008 (has links)
This work deal with different variants of the turning milling heads for CNC machines.The report depicts actual design solution of the turning milling head formilling machine, including technical report and economical conclusions.
19

Desenvolvimento de uma fresadora CNC de baixo custo para fins didáticos / Development of a low-cost CNC milling machine for teaching purposes

Sanches, José Matheus 30 January 2009 (has links)
Para o ensino em cursos relacionados à mecânica são fundamentais aulas teóricas e práticas de programação em máquinas CNC. Um grande incentivo para o aluno é ver sua programação transformada em uma peça que possa ser manuseada. Porém, dado o seu alto investimento, muitas escolas técnicas, de tecnologia e engenharia não disponibilizam máquinas CNC para os alunos. Desta forma, é apresentado neste trabalho o desenvolvimento de uma fresadora CNC de baixo custo. Com o emprego do método de combinação de variantes e o método de análise morfológica, os elementos mecânicos para o projeto da fresadora foram selecionados. Assim, foi possível desenvolver o conceito desse equipamento e fazer a estimativa de seu custo. Com a aplicação de análise de valor, utilizando as técnicas FAST, de Mudge e COMPARE, foi possível avaliar pontos críticos que acarretam em custos desnecessários. Com isso, pode-se avaliar como trabalhar com a transferência de recursos. / Courses related to mechanical sciences must offer to their students theoretical and practical lectures on CNC machine programming. The possibility of viewing the transformation of a programme in to a manageable part constitutes an incentive to the students. A CNC machine is an essential piece of equipment for such practical classes. A number of schools cannot have a CNC machine because of its high cost. Thus, in the present work, the development of a low-cost CNC milling machine as an alternative for academic purposes is presented. For the selection of the mechanical elements of the CNC machine, a combination of variants method and morphological analysis was used. Then, the design concept was carried out and its cost estimated. Using the value analysis through the FAST, Mudge and COMPARE techniques, the critical points that could increase unnecessary machine cost were examined. It was possible to assess how to work with the resources transference.
20

Development of a Small Envelope Precision Milling Machine.

Kirk, Dean Frederick January 2006 (has links)
The credit card industry is huge with over two and a half billion cards shipped annually. A local card manufacturer, with a production volume in excess of forty million cards annually, approached the University of Canterbury to design and develop advanced card manufacturing technology. The motivation behind this development was the desire of the sponsoring company to keep abreast of new technologies and to have the ability to manufacture and supply cards with this new and emerging technology into a highly competitive world market. This thesis reports the research surrounding the development of a dedicated new machine tool explicitly designed to implement the emerging technologies found in the international credit card industry. The machine tool, a dedicated milling machine, was not developed in its entirety within these pages; however, three major constituents of the machine were researched and developed to a point where they could be implemented or become the subject of further research. The three areas of interest were; • A machine table system that avoided the increased zonal wear to which linear bearings are subject, typically due to short high frequency traversals, and also the high friction and mass generally found in dovetail slides. • Design requirements demanded the use of a single commercially available carbide cutter to produce 1500 components per hour. Therefore, a purpose built high (revs per minute) rpm spindle and drive system specifically for use with polymeric materials, (R-PVC in particular) was deemed necessary. • Tracking the cutter depth in relation to an RFID aerial track embedded within the credit card core. The aerial tracking was to be dynamic and occur during the machining process with the machine “remembering” the depth of cut at contact with the aerial. Each of the three areas was researched via an in-depth literature review to determine what and if any material had been published in these fields. For the development of the machine table a novel flexure hinge idea was considered. Considerable material was discovered about flexures, but very little was found to be relevant to the application of high displacement metal flexures necessary to meet the required levels of table movement. In effect the proposed machine table system and research in this field would be novel. The high performance spindle investigation became directed into a much narrower focus as it progressed; that of determining the power consumption required to machine the integrated circuit pockets in an R-PVC work piece. This was due to the lack of information pertaining to the physical properties of polymeric materials, in particular the specific cutting pressure. The depth following sensor array was configured using capacitance detection methods to determine the distance between the cutter?s end and the aerial tracks. Capacitance sensing methods, whilst not new, were developed into a novel arrangement to meet the specific cutter tracking requirements of the proposed new machine tool. Each of the respective development areas had concept designs completed and were prototyped before being tested to determine the effectiveness of the respective designs. The outcomes from the testing are reported herein, and show each constituent part to be basically feasible, in the application. The results were sufficient to indicate that each development showed distinct potential but further development and integration into the machine tool should ensue.

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