Zasnova in izdelava dinamsko ustrezne velike CNC naprave

zaključna naloga Razvojno raziskovalnega programa I. stopnje Strojništvo

Tilen Košir (Author), Janko Slavič (Mentor)

Abstract

Zaključna naloga opisuje zasnovo in izdelavo velike dinamsko ustrezne CNC naprave. Zasnova je opravljena z izbiranjem konstrukcijskih rešitev preko primerjalnih matrik, s preliminarnim statičnim izračunom, ter z modalno analizo lastnih frekvenc naprave po metodi končnih elementov. Namen modalne analize je dvig najnižjih lastnih frekvenc konstrukcije že v razvojni fazi konstruiranja, s čimer se izognemo kasnejšim večjim amplitudam pomikov, ki vplivajo na kakovost obdelave izdelkov. Zaradi predvidene obdelave različnih materialov z različnimi rezalnimi orodji in obdelovalnimi parametri je vzbujevalna sila neznana, zato je bilo napravo z dinamskega vidika pred izdelavo mogoče optimirati le z dvigom najnižjih lastnih frekvenc. V delu so opisane potrebne poenostavitve naprave za ustrezno mreženje konstrukcije s končnimi elementi. Celotna naprava je bila analizirana postopoma po delih, ki so ekvivalentni konstrukcijskim podsestavom X, Y in Z osi. S pomembnimi konstrukcijskimi dodatki je bil dodelan le podsestav X osi, katerega najnižji lastni frekvenci sta bili povečani za faktor 2.1 in 3.1. Nazadnje je bila izvedena še modalna analiza celotne CNC naprave. V nadaljevanju je opisan postopek detajlnega konstruiranja CNC naprave, izvedba krmiljenja s koračnimi motorji, ter sama izdelava in montaža naprave.

Keywords

diplomske naloge;CNC;mehanska nihanja;modalna analiza;metoda končnih elementov;konstruiranje;izdelava;

Data

Language:	Slovenian
Year of publishing:	2018
Typology:	2.11 - Undergraduate Thesis
Organization:	UL FS - Faculty of Mechanical Engineering
Publisher:	[T. Košir]
UDC:	621.9.01:531.3:658.5(043.2)
COBISS:	16360731
Views:	1271
Downloads:	497
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Design and manufacturing of dynamically optimized large CNC machine
Secondary abstract:	The final thesis describes the design and manufacture of a dynamically optimized CNC machine. The design itself was developed through initial selection of design solutions using comparison matrices, preliminary static calculations, and modal analysis of natural frequencies of the CNC machine using the finite element method. The purpose of the modal analysis was to increase the critical natural frequencies. By doing that, the vibration amplitudes were decreased, which results in increased quality of machined parts. Since the induced vibration forces were not known due to a great variety of used tools and materials it was possible to optimize the machine only by increasing the lowest natural frequencies. To ensure proper meshing of the machine elements with finite elements some significant simplifications were made in order to ensure stable and fast convergence of the results. The analysis was conducted in stages. In each stage, X, Y, or Z axis subassembly was analyzed. The optimization process resulted in an increase of two X axis's natural frequencies by a factor of 2.1 and 3.1, respectively. Finally, the whole CNC machine was analyzed. The thesis further describes the machine's detailed design, motion control using stepper motors and manufacture.
Secondary keywords:	CNC;mechanical vibrations;modal analysis;finite element method;machine design;manufacture;
Type (COBISS):	Final paper
Study programme:	0
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. v Ljubljani, Fak. za strojništvo
Pages:	XIV, 63 f.
ID:	10957610