【作者】 陈雷；

【导师】 江征风；

【作者基本信息】 武汉理工大学 ， 机械制造及其自动化， 2009， 博士

【摘要】 汽车动力传动系统是一个多自由度的扭转振动系统,其扭振与噪声影响了汽车的安全性与舒适性,其中发动机转速与扭矩的波动是动力传动系统的扭振激励的主要因素。由于传统的离合器从动盘式扭振减振器受限于空间结构,减振效果有限。双质量飞轮作为一种新型扭振减振器,具有良好的减振性能,在国外得到了越来越广泛的应用。国内在此领域仍处于理论研究阶段。通过对双质量飞轮国内外的研究成果以及发展趋势的分析,以周向长弧形弹簧式双质量飞轮为研究对象,在双质量飞轮转动惯量分配、各级扭转刚度取值以及长弧形弹簧弹性特性方面进行了深入研究。首先,根据汽车动力传动系统的扭振当量原则与方法,分别建立了怠速工况与正常行驶工况下发动机、双质量飞轮以及传动系统的无阻尼多自由度扭振当量模型。在系统扭振模型的基础上,根据机械动力学与双质量飞轮的弹性特性,建立了双质量飞轮的设计模型,即第1阶设计模型、第2阶设计模型。其次,在双质量飞轮设计模型的基础上,分析了双质量飞轮转动惯量系数、扭转刚度、变速器与系统扭振频率的关系。进而,提出了双质量飞轮转动惯量系数、第1级扭转刚度的设计方法以及双质量飞轮与变速器匹配的方法。通过对周向长弧形弹簧安装形式的分析,推导出第2级扭转刚度与第1级扭转刚度的关系,从而得到第2级扭转刚度的设计方法。同时,提出了在正常行驶工况下优化第1、2级扭转刚度的原则与方法。在完成扭转刚度设计后,针对长弧形弹簧的结构特点,采用离散化方法对长弧形弹簧的弹性特性进行分析,推导出了长弧形弹簧的弹性特性公式,并讨论了其适用条件。第三,利用双质量飞轮怠速实验与静刚度实验验证双质量飞轮设计模型与设计理论的正确性。利用该设计方法,为VM柴油发动机匹配周向长弧形弹簧式双质量飞轮,并通过动力学仿真验证其工作性能。同时,通过对双质量飞轮动力传动系统的固有频率与扭振振型的分析,研究双质量飞轮的固有扭振特性。最后,利用VC++编程语言,将双质量飞轮设计理论与固有扭振特性分析方法集成到双质量飞轮设计与分析软件系统,具有较大的实用价值。更多还原

【Abstract】 The vehicle power train is a multi-freedom torsional vibration sytem, and its torsional vibration and nosie decrease the safety and comfortableness of a vehicle. The torsional vibration of the vechile power train originates from the fluctuation of engine rotating speed and torque. The traditional clutch damper has finite damping performance due to its space structure constraint. Dual Mass Flywheel (DMF), as a new type torsional damper, has favorable work performance, and then is widly applied into the passenger cars in overseas. However, the present status of development in this field still rest on the theory research stage in China.Based on domestic and abroad research results and development trend about DMF, the Circumferential arc spring Dual Mass Flywheel (CS-DMF) is taken for the study object in this thesis, the method of DMF is further studied, which includes rotary inertia coefficient ascertain, optimization of each torsional stiffness and elastic characteristics of Circumferential arc spring.First of all, the two undamped multi-freedom torsional vibration models of DMF under idling and driving condition are built based on the principles of vehicle power train equivalent torsional model. According to mechanical dynamics and the elastic characteristic of DMF, the design model of DMF is built, that is, the first order model and the second order model.Secondly, the relationship between rotary inertia coefficient, torsional stiffness, transmission gearbox and torsional vibration frequency is analyzed on the basis of the design model. Furthermore, a design method of rotary inertia coefficient and the first level torsional stiffness and the matching method of DMF and transmission gearbox are proposed. Afterwards, the relationship between the first level torsional stiffness and the second level torsional stiffness is derived out on the basis of the installation form of the springs so that the design method of the second level torsional stiffness is established. Moreover, the optimization principle and method of the two levels torsional stiffness under driving condition is studied. In the later, the elastic characteristics of the spring is analyzed by the discrete method, and then the calculation formula for the elastic characteristics is derived out, and also the suitable conditions of the formula is discussed. Thirdly, the design model and design method of DMF are verified by torsional vibration experiments under idling condition and static stiffness experiment. Furthermore, a CS-DMF is matched with the VM diesel engine based on this method, and then its performance is verified by dynamic simulation. The nature torsional vibration characteristics are studied by analyzing the nature torsional vibration frequencies and torsional vibration shapes.Finally, the software system of DMF design and analysis which integrates the design method of DMF and the analyzing method of nature torsional vibration characteristics of the vechile power train is developed by VC++programming language.更多还原