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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.
91

Café85 : En miljövänlig Café Racer

Sonesson, Alexander, Nanzell, Ola January 2010 (has links)
etanolkonvertering
92

Structural analysis of a washer machine cylinder

Eklind, Alexander January 2010 (has links)
This thesis focuses on the structural behavior of a washer machine cylinder. The cylinder is the component in the washing machine that rotates and keeps the laundry in place. The aim of this thesis is to determine the maximum load applied to the cylinder at which crack propagation occurs. Three experiments are performed to determine the structural behavior of the cylinder. Two experiments are performed to estimate mechanical properties i.e. stress-strain relation and critical fracture energy of the stainless steel sheet in use today. This is to derive a good estimation of the maximum load the cylinder can endure. The third type of experiment is performed to determine the strains on the outer surface of the cylinder when an evenly distributed load, 11 kg, and 2200 revolution per minute are applied on the inner surface of the cylinder. Three numerical models are performed from these three types of experiments which gives an estimation of the work to be done to propagate the crack at 15 kg and 2400 rpm. The question is if this load is overestimated to start crack propagation? This load is considerably higher than the washer machines operating speed.
93

Alternativ Start till Motorsåg : Reviderad för allmänheten

Olofsson, Christian, Cenanovic, Mirza, Ahmad, Khaled January 2010 (has links)
E-Series 450 is a chainsaw designed by Husqvarna AB to the semi-professional user. Husqvarna is a world leader when it comes to chainsaws, trimmers, lawn mowers and garden tractors. The problem in hand can be addressed by the question. ”How easy can we start a chainsaw” The purposehas been to provide a solution to the question above and give Husqvarna a good base of which they can continue towards a finished product. The goal of the project has been to construct a working prototype for a series of test runs.The project has involved a pre- study that resulted in a number of concepts which were evaluated in batches in order to come up with a concept that seemed durable enough to proceed with into the primary formation and construction.The work has, after a decision, mostly involved downsizing and optimizing of the different parts which have been designed in Catia V5 R18 for prototyping.SammanfattningTwo prototypes have been created during the project, the first as a base to the later, and have been tested and evaluated.The project has resulted in a prototype with two alternatives to start with. The result gives the user an easy and effective start process.The conclusion we can draw after the work is that the new design offers a simplified startup process for the user. The project team considers itself to have achieved the objective of the project.To simplify for the reader, a stand-alone part containing calculations and dimensioning has been made where those who want to immerse themselves in the underlying calculations and information which creates the foundation of the decisions made throughout the project.
94

V3 : Vertikalt vindkraftverk från prototyp till produkt

Sandin, Mattias, Lagerholm, Alexander January 2010 (has links)
Rapporten beskriver konstruktionsarbetet av det vertikala vindkraftverket V3 från prototyp till produkt. Det är det nystartade företaget Windforce som arbetar med att ta fram smarta hybridsystem där V3 är en del i konceptet. En serieproduktion av V3 är planerad till hösten 2010. V3 är klassat som ett litet vindkraftverk, har en rotordiameter på 3 meter och en kapacitet på 5 kW. Vindkraftverket kräver inget bygglov i Sverige och ska säljas till gemene man som vill bli självförsörjande på el. Denna rapport utgår från den befintliga prototypen, tillverkarens direktiv och myndigheters krav för att produkten ska bli så bra som möjligt. De områden som berörs är konstruktion, FEM beräkningar och certifiering. Den internationella vinklingen på rapporten belyser möjligheterna och användningsområden för V3 i utvecklingsländer med bristande infrastruktur. Förändringar på konstruktionen görs för att förbättra till exempel, luftfolier för bättre effektivitet och vajrar mellan ekrarna för att stärka hållfastheten. Dessutom görs det vissa standardiserade detaljer för att sänka tillverkningskostnaderna. Lager till vindkraftverket väljs för att bättre passa konstruktionen och delar av CE-märkningen görs.
95

Modernisering av driv- och vändstation för timmersortering

Kihlgren, Erik, Masterdalshei, Jonas January 2010 (has links)
The purpose of the rebuild of Notnäs AB timber sorting line is to renew the existing drive and turning ends of the transport chain, which has become old. This means that Notnäs AB have problems to get new parts if the gearbox and chain are worn out. They also require that the rebuild should have a maintenance schedule for the new spare parts that will be used in the rebuild. Maintenance workers placed great emphasis on that in a rebuild it shall be a service-friendly design. The maintenance schedule used in Notnäs AB in the current situation is from Statoil and the report uses SKF formulas and recommendations in order to obtain a lubricating schedule. The rebuild has been made in Pro Engineers skeletal structure with a top-down structure. Notnäs AB will have all the CAD files as well as complete drawings that make it possible for the rebuild to take place after the summer of 2010. After a summary of the CAD it revealed that a rebuild of timber sorting line was possible. Parts of the draw-ings are available in a reduced format of the report. Drawings have been approved and work on the rebuild can be started by Notnäs AB.The purpose of the rebuild of Notnäs AB timber sorting line is to renew the existing drive and turning ends of the transport chain, which has become old. This means that Notnäs AB have problems to get new parts if the gearbox and chain are worn out. They also require that the rebuild should have a maintenance schedule for the new spare parts that will be used in the rebuild. Maintenance workers placed great emphasis on that in a rebuild it shall be a service-friendly design. The maintenance schedule used in Notnäs AB in the current situation is from Statoil and the report uses SKF formulas and recommendations in order to obtain a lubricating schedule. The rebuild has been made in Pro Engineers skeletal structure with a top-down structure. Notnäs AB will have all the CAD files as well as complete drawings that make it possible for the rebuild to take place after the summer of 2010. After a summary of the CAD it revealed that a rebuild of timber sorting line was possible. Parts of the draw-ings are available in a reduced format of the report. Drawings have been approved and work on the rebuild can be started by Notnäs AB.
96

Konceptutveckling för lampdesign : The developing concept of lamps

Jansson, Jenny, Madsen, Maria January 2008 (has links)
Abstract This thesis was conducted by Jenny Jansson and Maria Madsen, students at the Faculty of Technology and Science and the Innovation and Design Engineer programme at Karlstad University, during the spring 2008. The thesis covers 22,5hp for each student. Anna Holmquist and Chandra Ahlsell at the company FOLKFORM were the ones who requested the theis, their company are located at Stora Skuggan in Stockholm. Tutor for this thesis was Lennar Wihk and the examiner was Monika Jakobsson of Karlstad University. The given assignment came from FOLKFORM and the aim for the thesis was to create a further development of two already existing lamps from an earlier collection at FOLKFORM, “Jaipur” and “Modern Times”. The students used their creativity and ability to come up with fresh ideas and new innovations with the lamps current design, but also considering material, manufacturing methods and the environment. Throughout the working process it was evident to create an exclusive concept yet a cheap concept for each lamp, where the main criteria were to make the material enlighten the feeling. Apart from these concepts new ones for the packing was to be evolved, one concept for each one of the lamps. Through extensive research of materials, production methods and the market and consumer needs, which generated in many ideas. The final stage was with the product of a concept development. The chosen concept then generated in this thesis, with concept developing and prototype developing, and four actual products, well conducted concepts of the lamps Palmett and Rotation in the final stage. The result of the thesis was, as mentioned above, four prototypes in 1:1 scale, an exhibition, a PowerPoint presentation and a written thesis report. Expectations are that FOLKFORM are willing to use the concept made by the two students in their own making when it comes to the developing of earlier collections, were the lamps are represented.
97

Topology Optimization of Gear shifter Housing and Contact Benchmarks

Kalidindi, Naresh, Fardmoshiri, Mohamad January 2010 (has links)
In automotive component design criteria such as weight, strength, stiffness, manufacturing cost are sensitive issues for boosting its performance which in turn has direct impact on fuel economy and cost.   This thesis deals with the design of gear shifter housing for Volkswagen car by using modern topology optimization techniques to the existing design. gear shifter housing holds the shifting mechanism and guides the lever to select the respective gear for different speed. Optimizing the design in terms of topology, material and structural is very important in arriving at practical solution.   To determine the optimum material layout distribution of material within the component with given set of loads and boundary conditions by placing a constrain on volume by minimizing sum of weighted compliance as well as maximizing lowest eigen value frequency. The process starts by applying loads to the gear shifter and constraining it in all directions thereby making the gear shifter a stiff design which can withstand loads from all direction. Boundary conditions play a major role in designing the component geometry.   Contact formulation has been complex task from several years. Optimization with contact for minimizing the volume by maintaining uniform deformation between  contact surfaces between two commercial softwares, HyperWorks V10.0 and TOPO4ABQ has been compared with benchmarks.   By using these techniques weight reduction has been achieved in automobile gear shifter housing and benchmarks with contact condition had been compared using Altair OptiStruct V10.0 and TOPO4ABQ by Niclas Strömberg.
98

Individen - kreativitet och kontext

Hanson, Linnea January 2010 (has links)
Companies and organizations need to take care of their employees’ creative ability. This report gives some examples of work situations that support or prevent creativity. The purpose with this report is to investigate the link between people at work and creativity. It was necessary to delimitate the area and decide which sources to be investigated and presented in the report. The main topic is on sources of creativity, but as more organizations seem to introduce efficiency thinking according to Börnfelt (2009), the interaction between efficiency and creativity is also presented. In this report theory is compared to industrial designers’ opinions on creativity. The empirical data consists of a survey which includes the answer from 15 industrial designers at two industrial companies. In the analysis it appeared that the empirical data supported the theory on several points. Some conclusions that can be drawn are that challenge, trust, low influence from a client, great support and good resources in a workplace can benefit creativity. Factors that can prevent creativity are downsizing in the organization, time pressure, a great extent of top management control, poor group dynamic and high demands. For detailed explanations of these conclusions the entire chapter 7 should be read. All individuals are different and this leads to a workplace that affects a person’s creativity and wellbeing in many ways. You have to design the workplace and to make it work, so that as many people as possible enjoy their work. What guidelines you could follow to get the ideal workplace are discussed in this report.
99

Lastkännande hydraulik Spirit 600

Johansson, Ted January 2010 (has links)
Detta examensarbete är gjort för Väderstadverken AB i syfte att utreda om det är möjligt och vilka effekter det får att implementera lastkännande(Ls) hydraulik på såmaskinen Spirit 600. För att kunna avgöra om Ls-hydraulik är lämpligt till såmaskinen har en prototyp byggts och testats med två traktorer. Testerna baseras även på mätdata för att kunna utvärdera hur hydrauliken beter sig. Av gjorda tester har det fastställts att Ls-hydraulik är en bra metod för att förbättra och förenkla hydraulsystemet. Då hydraulblocket till prototypen ej är lämplig för serieproduktion ur kostnads synpunkt har även två alternativa hydraulsystem tagits fram. Förslagen är baserade på användning av patronventiler. Fördelar med att bygga systemet med patronventiler är att dessa är billigare än slidventiler som används till prototypen och man kan göra unika block. Efter jämförelse med det befintliga hydraulsystemet kan man påvisa att användande av Ls-hydraulik kan bli billigare i konceptnivå.
100

Utveckling av rotationshuvud till CNC-testbänk

Hjelm, Alexander January 2010 (has links)
The thesis was written during an internship at ProCom GmbH in Aachen, Germany. It is a project with the goal to upgrade their already existing three linear axis test bench with two additional rotary axes. The task is to either find an already existing solution or to design, manufacture and install a rotary head on the test bench. The test bench is used to simulate water jet, laser and plasma cutting machines and is designed for internal use by ProCom. It is used to test new developed algorithms of their CNC software but also to test newly developed hardware before it is introduced to the market. The test bench has its axis driven by electrical motors and the additional two rotary axes would also be controlled the same way. The test bench is operated without any process force which means that only its own weight will have to be taken into consideration. The background to this requirement of an extra two axis is that customers are starting to demand a five axis control system for their machines and therefore it must be possible to test and verify the software in a realistic environment. This degree thesis is mostly done with design characteristics and concern from the very start with pre studies, explanation of the machine to the very end of the project with a mounted rotary head. Amoung the proposed rotary heads from the pre-studies, two rotary heads were chosen to go further with to be developed, manufactred and installed. With a modular design, to change between the two heads is possible with only minor effort.

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