大学毕设论文__康明斯柴油机气门摇臂的结构分析.docVIP

摘要 在凸轮轴式配气机构的汽车发动机中，气门摇臂是很重要的零部件之一，控制着进、排气门的开闭。它由凸轮轴通过挺柱、推杆或直接与凸轮轴型线接触带动其摇转，通过杠杆作用将动力传递至气门，从而控制气门的开闭。在发动机稳定工作的状况下，气门摇臂的工作环境非常糟糕。摇臂在承受着大的脉荷下高频动3种：锻钢镀铬摇臂、镶块式摇臂以及滚轮式摇臂。 计算机辅助设计技术的快速发展，对汽车行业的产品开发提供了非常快捷的路径，技术人员能快速高效地发现零件设计中的不足，对零件形状及尺寸进行优化，优化零件性能，减轻产品质量，减短产品开发周期，降低开发费用[1]。 本文主要研究内容：1） 使用CATIA软件完成气门摇臂体的三维实体建模；2） 运用FEM软件（ANSYS-Workbench、Hyper works）对摇臂进行静强度分析、模态分析以及疲劳寿命分析。3） 根据分析的结果，优化摇臂结构，并重新进行合理性分析。4） 结合生产实际，对摇臂的进行工艺设计，完成摇臂毛坯的工艺设计。 关键词：气门摇臂；结构；有限元；优化；工艺设计 Abstract In the valve-train type automobile engine, the valve rocker arm is one of the important parts, controlling the inlet and exhaust valves open and close. It consists of camshaft by lifter, push rod or direct contact with the CAM shaft type line drive the rocking-turn, leverage to transfer power to the valve, to control the opening and closing of the valve. Under the condition of the engine work properly, rocker arm working conditions are very bad. Rocker arm is always under larger under high frequency pulse load swing, between it and the CAM is always in constant friction under impact load. Valve rocker arm and camshaft friction to loss of energy, reduce engine efficiency. According to the working conditions of the valve rocker arm, overhead camshaft engine rocker arm with good abrasion resistance, high rigidity, high strength, light weight and low friction factor and many other features, so the integral structure and single kind of material is difficult to meet the above requirements. Valve rocker arm engines at home and abroad by a number of studies are generally revolve around the above three aspects. Currently adopted by the structure of the form mainly has three kinds, namely the chromium plating forged steel rocker, rocker panel board type and roller rocker arm. With the rapid development of computer aided design technology, the development of auto products provides an extremely convenient way. Through this design approach, designers can timely and effectively discover a defect in a product design, optimi