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Gear Timing Mechanism for Valvetrains
Drdla, Adam ; Rasch, František (referee) ; Novotný, Pavel (advisor)
The objective of this thesis is to provide an overview of geared valvetrain. In introduction are described individual types of gears and their application in combustion engines. Then, the thesis is divided into three chapters. The first chapter provides a thorough analysis of geared valvetrain. Also, individual parts of valvetrain together with alternative methods of valve timing are briefly introduced. The chapter then follows to examine the working principle of gears, how forces and moments are transmitted, advantages of introducing helical gears instead of spur gears, different ways of gear manufacturing, gear material selection, heat treatment of gears and common gear failure mechanisms. The second chapter examines pros and cons of using geared valvetrains. The third chapter shows examples of how are geared valvetrains applied in tractors, trucks, ships, trains, cars and motorcycles. In the conclusion, the main advantages of using geared valvetrains are discussed and the whole thesis is summerized.
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Valvetrain mechanism of a four-cylinder in-line gasoline aircraft engine
Holeňa, Vít ; Kučera, Pavel (referee) ; Píštěk, Václav (advisor)
This diploma thesis focuses on the analysis and design of a valvetrain for an aircraft piston engine. Using the GT Suite simulation tool, the aim is to construct a dynamic model of the valvetrain, make corresponding calculations as well as some design modifications. The thesis begins with the introduction to aircraft engines and valvetrain in general. In the following chapters, a more detailed introduction to cam profiles as well as related topics is presented. In the practical part of the thesis, an analysis of contemporary design is conducted, followed by a proposed design of new cam profiles. A single-valve model as well as a model containing all valves is presented, taking the gas pressure in the cylinder into consideration. The FEM Ansys Workbench was used for further calculations. The conclusion of the thesis summarizes designed variants, and further possible steps are outlined.
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Gear Timing Mechanism for Valvetrains
Drdla, Adam ; Rasch, František (referee) ; Novotný, Pavel (advisor)
The objective of this thesis is to provide an overview of geared valvetrain. In introduction are described individual types of gears and their application in combustion engines. Then, the thesis is divided into three chapters. The first chapter provides a thorough analysis of geared valvetrain. Also, individual parts of valvetrain together with alternative methods of valve timing are briefly introduced. The chapter then follows to examine the working principle of gears, how forces and moments are transmitted, advantages of introducing helical gears instead of spur gears, different ways of gear manufacturing, gear material selection, heat treatment of gears and common gear failure mechanisms. The second chapter examines pros and cons of using geared valvetrains. The third chapter shows examples of how are geared valvetrains applied in tractors, trucks, ships, trains, cars and motorcycles. In the conclusion, the main advantages of using geared valvetrains are discussed and the whole thesis is summerized.
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New product installation simulation
Medonos, Michal ; Dlouhý, Martin (advisor) ; Kuncová, Martina (referee)
One of the products produced by Motorpal a.s. is a camshaft. Recently, the company signed a contract with Bosch company to produce new types of camshaft. The analysis of the impact of the contract on the production was made by simulation. To perform the simulation it was necessary to map the whole process. The simulation of the current state was made in the first phase. The results shew many uneffectivnesses in the process and lack of capacity of some workplaces. Some changes in the process were suggested and tested with the aid of the simulation. The best results were achieved when the single-item flow was used. In the second phase the production of a new type of camshaft was added to the simulation. Analysis of these results was divided into two parts. The new production was analysed in the first part and it was discovered that the planned capacites are very deficient. The impact of the new production on the current one was analysed in the second part. It shew that this impact is negativ, especially on the duration of production.
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