Detta arbete beskriver förarbete och konstruktion av en stegmatare som sorterar och orienterar vevstakar för en takttid på tio sekunder. Industrier är ofta beroende av materialhanteringsutrustning där olika processer säkerställer någon form av sortering eller orientering, vilket styrker arbetets relevans. Detta har skett genom att dela in maskinen i två huvudfunktioner; trappfunktionen, som försorterar och transporterar vevstakarna vidare till andra huvudfunktionen; orienteringsfunktionen, där orienteringen sker. Genom att tillämpa metoder inom; konstruktion & tillverkning, feleffektsanalys och programvaror för materialdatabashantering, datastödd design, samt numerisk hållfasthetsanalys kunde en konstruktion utformas som speglar de aspekter som kännetecknar en genomtänkt produkt. Sju olika designmetoder användes för att generera och utvärdera idéer i flera itererande steg. Tio undersökande experiment utfördes som ytterligare utvärdering av koncept samt underlag för vidare beräkningar och slutsatser. Utformningen av stegmataren resulterade i en enkelverkande lutande trapp med två rörliga trappsteg och ett statiskt mellan dem för överföring. En enkelmatning efter trappen i form av ett “skovelhjul” säkerställer att vevstakarna levereras en-och-en till orienteringsfunktionen samtidigt som den garanterar takttiden. En orienteringsfunktion bestående av ett “rullband” som med hjälp av friktion och tyngdpunktsförskjutning orienterar vevstakarna med vevänden först. Slutligen studerades tre kritiska områden i konstruktionen för vidare analys med finita element-metoden med godkända resultat. Samtliga mål för projektet uppnåddes, exempelvis har stegmataren färre unika komponenter än befintliga lösningar. Ambitionen var att utforma stegmataren med en låg grad av komplexitet och utan sensorer har genomsyrat hela projektet, vilket även har uppnåtts. / This work describes the preparatory work and construction of a step feeder that sorts and orients connecting rods in a cycle time of ten seconds. Industries are often dependent of different material handling operations which assures a specific material orientation, which validates the importance of this work. This has been done by dividing the machine into two main functions; Stair case-function, which pre-sorts and transports the connecting rods further to the second function, the orientation- function where the orientation is performed. By using methods such as; design for manufacture & assembly, failure mode & effects analysis and softwares for material database handling, computer aided design and numerical strength analysis a construction could be formulated which reflects the aspects that characterize a well-planned product. Seven different design-methods were used in order to generate and evaluate ideas in several iterated steps. Ten investigative experiments were conducted as an additional evaluation of concepts and as a basis for further calculations and conclusions. The formulation of the step feeder resulted in a single-acting stair with two moving stairs and a static between them for transfer. A single-feeder after the staircase in the shape of a “paddle wheel” ensures that the connection rods are delivered one-by-one to the orientation-function while also ensuring the cycle time. An orientation-function consisting of a “conveyor“ that with the aid of friction and an offset of the center of gravity orients the connecting rods with the crankshaft-end first. Lastly were three critical areas in the construction further examined with finite element method with passing results. All objectives for the project were achieved, the step feeder have for instance fewer unique components than existing solutions. The ambition was to design the step feeder with a low grade of complexity and without sensors have permeated throughout the entire project, which also was achieved.

Orientador: Katia Lucchesi Cavalca / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-12T19:28:08Z (GMT). No. of bitstreams: 1 Daniel_GregoryBregion_M.pdf: 2663262 bytes, checksum: f7c1b338ec3a0dad168c82dc8c8d2fc2 (MD5) Previous issue date: 2008 / Resumo: Este trabalho visa analisar o comportamento dinâmico do sistema pino pistão. Por esse motivo, foi desenvolvido um modelo matemático para o mecanismo biela-manivela, considerando a influência do mancal hidrodinâmico da junção biela-pistão. As análises dinâmicas desse sistema foram realizadas utilizando dois modelos distintos. O primeiro modelo foi usado para representar o sistema quando o pino pistão está em contato com a superfície do mancal, assumindo, nesta condição, um comportamento similar aos mancais rígidos (sem folga). O segundo modelo foi empregado para representar o sistema quando o pino pistão está em lubrificação hidrodinâmica. Nesta condição, o pino pistão tem um movimento relativo à biela, o que torna este sistema um problema de múltiplos graus de liberdade. Diante disso, o primeiro modelo foi desenvolvido através da Equação de Movimento de Eksergian, sendo o segundo modelo, desenvolvido a partir do método de Lagrange. O modelo matemático de lubrificação hidrodinâmica foi introduzido com o intuito de obter resultados mais realísticos sobre o comportamento dinâmico do sistema. Este modelo de lubrificação considera as mesmas suposições básicas da teoria de lubrificação de Reynolds. A partir do modelo desenvolvido neste trabalho foram obtidas as orbitas do pino pistão, as distribuições de pressão e as velocidades e acelerações do mecanismo biela-manivela, o que permitiu realizar uma análise preliminar do comportamento dinâmico desse sistema. / Abstract: This work aims to analyze the dynamic behavior of the piston pin system. For this reason, a mathematical model for the slider-crank mechanism was developed, considering the influence of the hydrodynamic bearing of the piston-connecting rod joint. The dynamic analyses of the system applied two distinct models. The first represented the system when the piston pin was in contact with the bearing surface, assuming, in this condition, a similar behavior of rigid bearings (without clearance). The second model represented the system when the piston pin was in hydrodynamic lubrication. Under this condition, the piston pin presented a relative motion to the conrod, what turns this system into a multidegrees of freedom problem. Therefore, the first model was developed by Eksergian's Equation of Motion and the second model was developed by Lagrange method. The mathematical model of hydrodynamic lubrication was introduced to obtain more realistic results under the system's dynamic behavior. This lubrication model considers one of the basic assumptions of the Reynolds lubrication theory. From the model developed in this work were obtained the orbits of the piston pin, the pressure distributions and the velocities and accelerations of the slider-crank mechanism, what allows a preliminary analysis of the dynamic behavior of this system. / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica

Le but de ce travail est de proposer une démarche structurée pour l'étude des liaisons lubrifiées bielle/vilebrequin. Bien que cette source de déperdition énergétique ne soit pas primordiale, il n'en est pas moins vrai que la maîtriser est un enjeu pour les motoristes. Les normes anti-pollution imposées aux constructeurs automobiles étant de plus en plus strictes, un effort doit être réalisé sur l’ensemble des composants afin de réduire de façon significative les pertes d’énergie dans les moteurs. La tendanceactuelle est à la diminution de la viscosité du lubrifiant, toutefois ce n'est pas sans conséquence sur l'intégrité des liaisons.La démarche proposée, qui s'appuie sur un logiciel TEHD consiste à utiliser la méthode des plans d’expériences afin de créer des métamodèles de la puissance dissipée et de la sévérité du cas traité. Une optimisation multi-objectifs (déperdition et sévérité) par algorithme évolutionnaire et utilisant les métamodèles est ensuite menée afin de déterminer les combinaisons de facteurs offrant les meilleurs compromis par rapport à ces deux objectifs. La méthodologie proposée s'avère pertinente puisque des modèles analytiques simples se substituent très avantageusement aux lourds calculs TEHD.Afin de valider le logiciel TEHD sur l'évaluation des puissances dissipées, une comparaison numérique/expérimentale est conduite sur un banc d’essais permettant de reproduire les conditions réelles de fonctionnement des bielles dans les moteurs. / The aim of this work is to propose a structured approach of the study of the lubricated connection between the conrod and the crankshaft. Although this source of energy loss is not the most significant one, improving this contact remains a challenging task for engine manufacturers. The anti-pollution standards imposed on automakers are increasingly stringent, an effort must be made on all components in order to significantly reduce energy loss in the engines. The current trend is to decrease the viscosity of thelubricant, however, it is not without consequences for the connections health. The proposed approach, which relies on a TEHD software is to use the design of experiments method to create surrogates of both power loss and severity for the treated case. A multi-objective optimization (power loss and severity) by evolutionary algorithm and using the surrogates, is then performed to determine the right combination of factors that provides the best compromise with respect to these two objectives. The proposed methodology is relevant because simple analytical models replace very favorably time consuming TEHD calculations.To validate the evaluation of power loss calculated with the TEHD software, a numerical/experimental comparison is performed on a test bench which reproduces the real operating conditions of the connecting rods.

Le moteur à combustion, utilisé dans l’automobile est en perpétuelle évolution pour des raisons économiques et écologiques. Pour parvenir à de faibles consommations de carburant et émissions polluantes, l’un des axes étudiés est la réduction des pertes mécaniques par frottement du moteur qui constituent 15 à 20% de la consommation totale d’énergie du moteur. 50% de ces frottements proviennent des contacts Segment-Piston- Chemise et de la liaison Maneton-Bielle-Coussinet. De ce fait la compréhension de la tribologie de ce contact, l’optimisation de la lubrification et le vieillissement des lubrifiants deviennent primordiaux. L’objectif de cette thèse est d’étudier les mécanismes de lubrification de ces contacts segment/chemise et maneton/coussinet, et en particulier de comprendre l’influence du couplage additif, surface et matériau dans les différentes régimes de lubrification. Il s’agira de répondre à la question : comment maîtriser le frottement et l’usure en contrôlant la chimie du lubrifiant, la topographie et le matériau ? La démarche expérimentale choisie s’appuie sur l’analyse du comportement tribologique de deux additifs modificateurs de frottement sans cendres d’une part, puis sur l’impact du matériau et enfin sur l’influence de la topographie d’autre part. L’analyse de la cinétique d’évolution du coefficient de frottement et des traces d’usure en régime limite ont notamment permis d’identifier les mécanismes de réduction de frottement induits par les deux modificateurs étudiés. / The combustion engine used in automotive industry is constantly changing for economic and ecological reasons. To achieve low fuel consumption and pollutants emissions, one of research axes studied is the reduction of the mechanical friction loss of the motor which constitute 15-20 % of the total energy consumption of the engine. 50% of these come from friction contacts cylinder /piston rings and conrod bearing. Thereby understanding of tribology of the contact, optimizing lubrication and lubricants aging become paramount. The objective of this thesis is to study the mechanisms of lubrication of these contact (piston ring/cylinder and conrod bearing), and in particular to understand the influence of the additive coupling surface and material in the different lubrication regimes. This will answer the question : how to control the friction and wear by controlling the chemistry of the lubricant, the topography and the material ? The experimental approach chosen is based on the analysis of the tribological behavior of two friction modifiers additives ashless at first time, and on the impact of material and finally the influence of topography on the second time. XPS Analysis of the evolution of the coefficient of friction and wear track under boundary regime have enabled to identify mechanisms to reduce friction induced by the two modifiers studied.