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Active Damping of Machine Tool Head
Škúci, Michal ; Marek, Jiří (referee) ; Březina, Tomáš (advisor)
The master’s thesis deals with building mechatronics model of machine tool head delivered by company TOSHULIN,a.s. for purpose of damping vibration. Mechanical part of the model is based on modeling of system of flexible bodies. Components are modeled in FEM program ANSYS and subsequently reduced using Craig-Bampton method. The system of flexible bo-dies is created in MBS program ADAMS. Model is linearized and subsequently reduced. As a element of active damping is used linearized model of magnetic bearing. For control is desig-ned PID controller. The comparison of damped and undamped model is conducted in the end.
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Crank mechanism with a high mechanical efficiency
Drápal, Lubomír ; Tůma, Jiří (referee) ; Páv,, Karel (referee) ; Píštěk, Václav (advisor)
This document describes the possibilities of increasing the mechanical efficiency of the crank train of an internal-combustion engine. For this purpose, a concept with a reduced number of main bearings is chosen and its contribution is verified experimentally. The proposed solution consists of an innovative crankshaft design of a four-cylinder spark-ignition engine with only three main journal bearings and laser-welded sheet metal crank webs. The new design is compared to the mass-produced one in terms of friction losses, vibrations and loading of engine parts by means of simulations of crank train dynamics using the Multi-Body System. The increase in vibration, accompanied by a reduction in friction losses, is compensated by a torsional vibration damper and its effect is experimentally verified. Experimental research of laser welds on the crankshaft in terms of fatigue life is also described. The overall potential is also summarised and further possible development of this innovative and patented design is outlined.
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Simulation Assessment of X Axis Damping Possibilities of Heavy Machine Tool
Štetina, Jakub ; Marek, Jiří (referee) ; Březina, Tomáš (advisor)
This master's thesis deals with the simulation assessment of axis X damping possibilities of Heavy Machine Tools. CAD model has been provided by company TOSHULIN a.s. In the thesis, there is described modelling of axis X as multi body system consisting of rigid and flexible bodies. The main goal is to create simplified model and get the information for strategic decision of manufacturer about damping possibilities of axis X. For the solution has been used several software products: SolidWorks 2013 - for simplifying the CAD models, Ansys 14.5. for modelling od flexible bodies, MSC.Adams for modelling multi body systems and Matlab 2012 for data processing and optimization.
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Turbocharger Rotors using Rolling Bearings
Šárovec, Marek ; Dlugoš, Jozef (referee) ; Novotný, Pavel (advisor)
The main purpose of this diploma thesis is to design turbocharger rotor using rolling element bearings. The diploma thesis is compiled from two specialized search parts dealing with turbocharger rotor and rolling element bearing computation, respectively. The application of the particular rotor using the multi body system Adams – View is described in the following chapter. In the last chapter, one can find the comparison between rotor using bearing with steal and hybrid ceramic rolling element. Also, there is compariosn between rolling element bearing and journal bearing. In the maximum rotor speed, the decrease of more than 50 % in power loss, due to usage of rolling element bearing, resulted from this comparison.
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Powertrain Vibration Solution using Computational Modelling
Zubík, Martin ; Prokop, Aleš (referee) ; Novotný, Pavel (advisor)
The thesis solves vibration of simple combustion engine model as a basic step for evaluating the noise of engine. On the basis of computational model realized in software MBS ADAMS, which contains all significant input parameters, there are found normal velocities of the one cylinder four stroke engine block surfaces. The outputs are then processed into the integral characteristics that define the level of possible emissions for whole acoustic spectre. Two variants of the engine block were solved and in the end the summary of solution approach was made.
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Solution of Powertrain Vibration on Dynamometer
Lux, Josef ; Janoušek, Michal (referee) ; Novotný, Pavel (advisor)
This diploma thesis deals with vibration of powetrain on dynamometer. For this problem I got six-cylinder engine, which is connected by flexible coupling to dynamometer. According to simplified computational model is this assembly simulated in MBS of system ADAMS View. Two versions of flexible coupling are dealt. In the final part of the thesis is created single program for calculation self-frequency of this assembly and in the end of this thesis is general evaluation.
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The virtual prototype in design process of the machine tool
Krejčiřík, Petr ; Hadaš, Zdeněk (referee) ; Vetiška, Jan (advisor)
This bachelor thesis discusses about possibilities of using virtual prototype in design stage of the machine tool. The virtual prototype can be divided into a visual and an analytical model. Both parts of the prototype are possible to analyze with the required criteria and thus obtain an optimal result of proposed object. These analyses effectively reduce costs during the design stage of the machine tool. Using of the virtual prototype ensures that the first manufactured piece is correct according to the required criteria. Compared with an access using a physical prototype is achieved far greater time and financial savings because there are not created non-usable parts.
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Interaction between Mobile Working Machines and Rolled Surfaces
Pokorný, Jan ; Hrabovský, Leopold (referee) ; Červinka, Jan (referee) ; Škopán, Miroslav (advisor)
This dissertation thesis is concerning with an interaction between mobile working machines and rolled surfaces. Machines and their constructions parts behavior were observed. There are some machines that can change state of surface. And due to these change of surface the machine is in different conditions for drive and also for works. The interaction of working machines and rolled surfaces was categorized in this work and for each category here is a methodic work flow for solution of various cases. Three examples are described in this work. Some simulating programs were used for all cases and therefore there is a methodic work flow for creating and simulating of models. Three described examples include a complex solution of hydraulic drive for vibration exciter of vibration roller, small cleaner of canalizations with aim on load case to frame of this cart. The third example describes solution of undercarriage frames of agricultural semi-trailers. This example is the most extensive chapter from this work due to including of marketing research at the beginning of development and also verification of simulated results with results from real prototype tests at the end of development of these undercarriage frames.
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Crank mechanism with a high mechanical efficiency
Drápal, Lubomír ; Tůma, Jiří (referee) ; Páv,, Karel (referee) ; Píštěk, Václav (advisor)
This document describes the possibilities of increasing the mechanical efficiency of the crank train of an internal-combustion engine. For this purpose, a concept with a reduced number of main bearings is chosen and its contribution is verified experimentally. The proposed solution consists of an innovative crankshaft design of a four-cylinder spark-ignition engine with only three main journal bearings and laser-welded sheet metal crank webs. The new design is compared to the mass-produced one in terms of friction losses, vibrations and loading of engine parts by means of simulations of crank train dynamics using the Multi-Body System. The increase in vibration, accompanied by a reduction in friction losses, is compensated by a torsional vibration damper and its effect is experimentally verified. Experimental research of laser welds on the crankshaft in terms of fatigue life is also described. The overall potential is also summarised and further possible development of this innovative and patented design is outlined.
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