Projeto de conjunto redutor de velocidade utilizando engrenagem sem-fim

This work is initially based in give a solution to a problem consisting of lifting a load in a warehouse focusing specifically on the solution´s project and comparison of the results obtained following the sequence of the book and comparing these results with the finite elements simulation based on the 3D components modeling. Starting from that was realized the project of the worm gear reducer to solve the problem and makes the work easier. The project consisted basically of the study, project itself and simulation by software of a worm gear reducer and projects steps, starting with the initial problem conditions (to lifting a load up to an specific height at a given time) following all the reducer project sequence, starting by the preliminary draft and electric motor selection using iterative process, material selection, worm gear dimensioning, axles, keyways, bearings and coupling. After that was performed the three dimensional modeling of the components using SolidWorks software and simulating these components using Ansys software. The results show the importance of the CAD in terms of improving project development speed and reducing costs with prototypes

Controle de velocidade de um motor de indução trifásico usando técnicas de ajuste empírico para bancada de teste no laboratório de automação

This work aims to make the closed loop control of a three phase induction motor, through the integration of the following equipment: a frequency inverter, the actuator system; a programmable logic controller (PLC), the controller; an encoder, the velocity sensor, used as a feedback monitoring the control variable and the three-phase induction motor, the plant to be controlled. The control is performed using a Proportional - Integrative - Derivative (PID) approach. The PLC has a help instruction, which performs the auto adjustment of the controller, that instruction is used and confronted with other adjustment methods. There are several types of methods adjustments to the PID controllers, where the empirical methods are addressed in this work. The system is deployed at the Interface and Electro Electronic Control laboratory in the Universidade Estadual Paulista Júlio Mesquita Filho, Guaratinguetá, São Paulo, then, in the future, this work becomes an experiment to be conducted in the classroom, allowing undergraduate students to develop a greater affinity to the programs used by the PLC as well as studies of undergraduate and graduate works with the help of assembly made

A evolução histórica da corrida de velocidade: um aprofundamento na prova dos 100 metros rasos

Existente desde os Jogos Olímpicos da Grécia Antiga, as corridas de velocidade ocupam espaço de destaque dentre as provas do atletismo. Em particular, os 100 metros rasos masculino é a prova cujas particularidades merecem ser investigadas, sobretudo em função das inúmeras alterações ocorridas ao longo dos anos. Por exemplo, a princípio, a corrida de velocidade era disputada nos Jogos Olímpicos da Grécia Antiga, com o nome de stádion ou dromo e com um percurso de 192,27 metros. Com a decadência e a extinção dos Jogos Olímpicos, a corrida de velocidade deixou de ser disputada, retornando em 1896, com o renascimento dos Jogos Olímpicos da Era Moderna. Entretanto, dentre as modificações nas provas do atletismo, as corridas de velocidade passaram a ser de 100 e 400 metros rasos, o bloco de partida passou a ser obrigatório etc. O objetivo desta pesquisa consiste em averiguar as principais modificações ocorridas na prova dos 100 metros rasos masculino, desde a sua origem até os dias atuais. Esta pesquisa, de caráter histórico-bibliográfico, tem a finalidade de resgatar a história da prova dos 100 metros rasos com base na história dos Jogos Olímpicos, verificando as alterações em suas regras básicas, em sua composição e técnicas específicas, a fim de reunir subsídios para o seu ensino em aulas de Educação Física. Com esta pesquisa, esperamos contribuir não apenas com o resgate da história desta ocorridas na prova dos 100 metros rasos masculino, desde a sua origem até os dias atuais. Esta pesquisa, de caráter histórico-bibliográfico, tem a finalidade de resgatar a história da prova dos 100 metros rasos com base na história dos Jogos Olímpicos, verificando as alterações em suas regras básicas, em sua composição e técnicas específicas, a fim de reunir subsídios para o seu ensino em aulas de Educação Física. Com esta pesquisa, esperamos... (Resumo completo, clicar acesso eletrônico abaixo)

Aplicação do método desirability para otimização de processo com múltiplas respostas

Currently, the competition between organizations in the pursuit of consumer preference has become increasingly fierce. In addition, consumers have become increasingly demanding due to high speed with which innovations occur, leaving the companies meet and sometimes surpass those expectations In this context, there is the necessity to use methods as mathematical models capable of dealing with the optimization of multiple responses simultaneously. In this context, this study presents an application of techniques of Design of Experiment in a machining process of a NIMONIC 80 alloy, a “superalloy” that has thermal and mechanical properties that make its machining difficult and in order to do this, the Desirability Function was used. As they are determining conditions in the machining capability of the alloy, the roughness and the cutting length were considered as variable settings, and the factors that can influence them are cutting speed, feed rate, cutting depth, inserts type and lubrication. The analysis of the result pointed out how was the influence of all factors on each response and also showed the efficiency and reliability of the method

Controle de velocidade e tração de rodas independentes para veículos elétricos

This work presents a proposal to replace thetraditional system of traction electric car that usesone electric motor and a mechanical differential, by two electric motors of lower power, controlled byelectronic control low cost. The proposed control isopen loop and uses the technique of Pulse WidthModulation (PWM), discrete and synchronizedaiming to reduce the generation of harmonics. The implementation of two smaller motor one on each wheel-drive distributes the weight of the vehicle, improving the heat exchange of the windings,beyond enable the power components supporting a current of 50% predicted for only one motor . The solution adopted for being open-loop, has a similar behavior to the mechanical differential, where theeffort imposed by the trajectory makes the velocity distribution between the wheels be appropriate tovehicle trajectory

Efeito da ativação física e química do gel clareador na velocidade de penetração do peróxido de hidrogênio: estudo in vitro

This study evaluated the effect of physical and chemical activation on the speed of penetration of hydrogen peroxide bleaching agents present in different concentrations through the enamel and dentin. One hundred and twenty bovine incisors were used, which were obtained enamel/dentin discs of the buccal surface, with 6 mm in diameter. The samples were divided into six groups: G1 - Hydrogen Peroxide Gel 20%, G2 - Hydrogen Peroxide Gel 20% with light activation, G3 - Hydrogen Peroxide Gel 20% with Manganese Gluconate; G4 - Hydrogen Peroxide Gel 35%; G5 - Hydrogen Peroxide Gel 35% with the light activation and G6 - Hydrogen Peroxide Gel 35% with Manganese Gluconate. The specimens were placed in a transparent support on which there was a substance sensitive to hydrogen peroxide immediately below and in contact with the specimen. After the procedures for applying the gel for each group, one video camera was positioned and operated to monitor the time of penetration of peroxide in each specimen. The recording ended after changing the color of the fluid revealed in all specimens and times were noted for comparison. ANOVA analysis showed that concentration and type of activation of bleaching gel significantly influenced the diffusion time of hydrogen peroxide (P 0.05). 35% hydrogen peroxide showed the lowest diffusion times compared to the groups with 20% hydrogen peroxide gel. The light activation of hydrogen peroxide decrease significantly the diffusion time compared to chemical activation. The highest diffusion time was obtained with 20% hydrogen peroxide chemically activated. The diffusion time of hydrogen peroxide was dependent on activation and concentration of hydrogen peroxide. The higher concentration of hydrogen peroxide diffused through dental tissues more quickly

Melhoria da qualidade de um processo de usinagem utilizando as técnicas de avaliação de Taguchi

Delivering to the customers a product or service with the expected quality associated to the huge competitiveness that exists in the market nowadays, has been making organizations increasingly focus on quality planning using techniques which are directed towards the continuous improvement process and production optimization. Thus, this paper aims to improve a machining process using the techniques of experimental design to the optimization and this also includes the analysis of the measurement system. For this purpose, the alloy Nimonic 80A, a nickel base superalloy, was used in the process due to its widespread use for high temperatures, applying this study the robust method proposed by Genichi Taguchi, determining the influence of the factors considered input variables, cutting speed, feed rate, depth of cut, type of tool, lubrication, and material hardness, in the output or response variable, surface roughness, concluding with the use of Taguchi orthogonal array L16 and by analysis of ANOVA that the factor feed rate is significant and offers greater effect on the response variable studied, should be set to 0,12mm/rev. Moreover, the factor type of tool has more influence on the process when compared to other factors, being CP250 the one more suitable to the process. Lastly, the interaction feed rate x cutting speed provides greater significance in the process regarding to surface roughness variable, being the best match between them 0,12mm/rev to the feed rate and 90m/min to the cutting speed. In order to evaluate the measurement system, it was applied the repeatability and reproducibility method (R&R), through which we saw that the system needs improvement (R & R = 88.04% >>> 30%) as the value found in the study was well above compared to the one that classifies the system as inappropriate

Usinagem da liga de níquel inconel 718 com pastilhas de cerâmica

The machining of super alloys resistant to high temperatures such as nickel alloys, inconel 718 specifically, is a very difficult job to obtain improvements in the process, due to the difficulty of machining at high cutting speeds, the use of these alloys in industries showed great developments in recent years, its application in aeronautical industry spread being used in vane turbo, compressor parts, props and set elements. The automotive, chemical, medical and others also took advantage of the great features of inconel 718 and has used the material. The high temperature resistant alloys have high machining difficulty, a fact that is associated with high cutting forces generated during machining which result in high temperatures. High levels of temperatures can cause deterioration of the cutting edge, with subsequent deformation or breakage, wear most common obtained in machining such materials are flank wear the formation of built-up edge for cutting and notch wear. The experimental part of the work consists in machining of nickel-based alloy Inconel 718 heat treated for hardness, using a tool based ceramic silicon nitride Sandvik (Si3N4) in order to compare the best results obtained in the master's thesis of SANTOS (2010) who used a tool ceramics also the basis of silicon nitride which was developed in the doctoral thesis of SOUZA (2005). Assays were performed on a CNC lathe and was noted for each cutting edge results obtained. Tests were made starting from an initial condition of the tool with cutting speed of 200 m/min, feed 0.5 mm and 0.5 mm depth of cut was reduced cutting speed for the subsequent tests with the same conditions of feed and depth of cut. The tool presented wear instant under two 200 m/min and 100 m/min, premature rupture of 50 m/min and finally cut provided with difficulty... (Complete abstract click electronic access below)

Modulação da velocidade do andar em indivíduos com doença de Parkinson em estágio leve e moderado

A doença de Parkinson (DP) é uma patologia crônica, degenerativa e progressiva acarretada pela perda de neurônios dopaminérgicos da substância negra (parte compacta), localizada nos núcleos da base. Os comprometimentos na marcha estão entre as principais consequências da DP. Entretanto, pouco se conhece sobre o efeito do estágio da doença na modulação da velocidade do andar. Assim, o objetivo do estudo foi verificar como pacientes em diferentes estágios da DP modulam os parâmetros do andar quando requeridos a andar em máxima velocidade. Os participantes do estudo foram indivíduos com DP idiopática em estágio unilateral (entre 1 e 1,5 na Escala de Hoehn & Yahr) e bilateral (entre 2 e 3 na Escala de Hoehn & Yahr). Inicialmente, os participantes foram submetidos a uma avaliação clínica, realizada por um médico neuropsiquiatra, para verificar o acometimento geral e o estágio da doença. Os dados da avaliação clínica foram utilizados para a distribuição dos participantes entre os dois grupos. Em seguida, os participantes foram convidados a andar sobre uma passarela de 10m de comprimento em duas condições experimentais: Velocidade preferida e velocidade máxima. Somente o grupo bilateral não foi capaz de modular o comprimento da passada na condição de velocidade máxima. Os resultados sugerem que a evolução da DP compromete a capacidade dos pacientes em modular a amplitude de movimentos (comprimento da passada) quando são requeridos a andar em velocidade máxima

Otimização do processo de usinagem da superliga nimonic 80A utilizando o Método de Taguchi

Atualmente, atender as necessidades dos consumidores é uma das metas mais importantes, os consumidores estão em busca de produtos com qualidade e preços mais acessíveis, para isso, é indispensável que as empresas se atualizem para melhorar seus produtos e serviços. Com este cenário, as superligas estão cada vez mais ganhando mercado, pois possuem ótimas propriedades, principalmente em relação a operar em temperaturas elevadas, podendo proporcionar maior eficiência para motores que necessitam trabalhar em altas temperaturas. Em contra partida a essa vantagem, as superligas possuem uma baixa usinabilidade, sendo importante a análise do processo de usinagem para se tornarem mais aplicáveis. Este trabalho visa à otimização do processo de torneamento cilíndrico da superliga Nimonic 80A, com o intuito de melhorar a qualidade do produto, utilizando o Método de Taguchi, com o arranjo ortogonal L16, sendo o comprimento de corte definido como variável resposta e analisados seis fatores que poderiam influenciar na sua variação, tais fatores são: velocidade de corte, avanço, profundidade de corte, tipo de pastilha, lubrificação e dureza do material. Os resultados obtidos demonstraram que os fatores avanço, tipo de pastilha e lubrificação são significativos e exercem influencia no processo, sendo que o avanço deve ser ajustado no nível de 0,12 mm/rev, a pastilha a ser utilizada deve ser CP250 e a lubrificação deve ser feita de maneira abundante, para a otimização do processo. Com a análise dos resultados, também podemos observar a eficiência e confiabilidade do método utilizado, mostrando resultados coerentes

Velocidade de semeadura e profundidade da haste em sistema plantio direto de milho e soja

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Acurácia e precisão na formulação não linear de ração para frangos de corte: avanço e otimização de resultados

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos dos parâmetros de usinagem no acabamento superficial de materiais cerâmicos a verde

Pós-graduação em Engenharia Mecânica - FEB

Estudo da influência do agente nucleante )ALTi5%B1%) na microestrutura de chapas AA8011 obtidas por lingotamento contínuo

The aluminum includes several properties with excellent relation between weight and mechanical resistance. With technological advances, increasingly demand the development of new alloys and other production processes in order to reduce the cost of production and insert these new alloys in broader applications. The process of continuous caster (TRC promoted the unite of the aluminum smelting process with the first stage of rolling, making it most economical through the merger these two phases besides transform the continuous casting process. The AA8xxx series is one of the most versatile aluminum alloys and the most often used in continuous caster process provided a great potential application in the market. In order to further, optimize the process it is necessary to increase awareness of the aluminum solidification phenomena associated with the addition of grain refiner, and control of some aluminum production parameters in the process (production rate, metal temperature, etc.). In this study, AA8011 alloy samples were taken in the raw state obtained by the continuous casting process. The samples were laminated to a thickness of 7mm during the process itself and analyzed at three points along its width by microstructural analysis throughout its thickness, the variation rate of addition of the grain refiner in order to assess the influence of this addition with crystallographic formation and some formation of intermetallic precipitates during the solidification. Through this work, it was possible to improve the knowledge related to the addition of refiner with the monitoring of these production processes