【作者】 郑楚彬；

【导师】 丁康； 宋庆佳；

【作者基本信息】 华南理工大学 ， 车辆工程， 2011， 硕士

【摘要】 汽车动力总成是汽车的动力源,主要由发动机和变速器两大部分组成,在新车的研发过程中,发动机和变速器的研发属于非常重要的部分。作者所在的汽车公司在开发一种自主品牌新车的过程中,发现该新车的动力总成在耐久试验和与汽车匹配过程中出现了轴瓦磨损和变速器在加减速时噪声大两个问题。本文通过试验和研究,找出新车开发过程中动力总成产生这两个问题的根本原因,并有针对性地采取措施对其进行改善,解决了动力总成开发问题点,同时制订出解决动力总成相关问题的分析参考方法。针对动力总成轴瓦磨损的故障问题,通过对零件装配情况、零件尺寸、材料化学成份和磨损表面形态进行分析,确诊此轴瓦磨损类型为黏着磨损;并对黏着磨损的可能原因(摩擦副材料、载荷、表面温度和润滑条件等)进行分析排查,找到轴瓦磨损的根本原因是加工不当导致轴瓦机油泄漏和润滑不良,从而引起轴瓦异常磨损;通过工艺变更和刀具改造防止轴瓦机油泄漏最终解决了问题。针对加减速时变速器齿轮噪声大的故障问题,通过采集变速箱行驶过程噪声和转速波动数据进行分析,找出变速器齿轮噪声大的原因离合器是刚度和阻尼选取不当,调整离合器刚度和阻尼后最终有效地减小了车辆加减速时发生的噪声。本文内容为典型的汽车动力故障分析,通过理论分析和试验指导零件规格变更与零件工艺变更,不仅解决了两个车辆动力总成开发过程的故障问题,而且形成了比较清晰的分析思路,为汽车的新车开发研究提供借鉴,具有较大的工程实用价值。更多还原

【Abstract】 As the power source of automobile, automotive powertrain consisting of contains engine and transmission mainly. In the process of new cars’research and development, engine and transmission are the important parts of it. When the the company, which the author works in, develops a car as self owned brand one, and in this process, two problems are exposed that the bearing pad wears seriously in in durability test and the transmission generating loud noise when the engine speed up and speed down in car matching for the new car’s powertrain. In this paper, the main causes and the solutions of the two problems above mentions are found and given. The paper not only resolves the powertrain problems, but also works out a relative analysis method for related issures of powertrain.Aiming at the wears seriously problem of bearing pad of powertrain, several steps are carried out. First, by analysing the components’assembling effect, dimensions, material chemical composition and the form of worn out surface are, the wear type of the bearing pad that is adhesive wear, are obtained. Secondly, the possible causes of adhesive wear, including the material of rubbing pair, load, surface temperature, lubrication condition and so on, are checked and analyzed. Then, the primary cause of bearing pad’abnormal wear is found that is unsuitable process leading to the leak of lubricating oil for bearing pad and poor lubrication. Finally, by improving processing technic and cutter to decrease the leak of lubricating oil for bearing pad, the bearing pad wearing problem is solved. Aiming at the fault problem of transmission generating loud noise when revolving speed changes, the noisy signals and the data of revolving speed’fluctuation collected from the transmission are analyzed, and the cause of loud noise of transmission is found that is improper rigidity and damping for clutch. The noise of transmission is decreased obviously by adjusting the rigidity and damping for clutch.The content of this paper is a typical automobile power fault analysis, the modifications of components’dimensions and processing technic is guided by means of theoretical analysis and test. The paper not only solves the fault problems in the process of the development of new car’s powertrain, but also obtains a relatively distinct analysis idea, which provides a reference for new car’development and engineering application.更多还原