【作者】 赵鹏云；

【导师】 黄茂林；

【作者基本信息】 重庆大学 ， 机械设计及理论， 2006， 硕士

【摘要】 机电产品的设计都是为了满足某种特定的功能要求,而这些功能要求往往是通过机构的动作来实现的。在众多的机构中,连杆机构是机构与机器理论中的最重要的基本机构之一,同时也可视为其他基本机构理论结构原形,所以在机构学理论与方法的研究过程中,通常首先以连杆机构作为研究对象。平面连杆机构一般均是应用V级低副连接形成具有封闭回路的结构,因而其约束也最具强制性。其约束结构的超静定性以及对制造、安装和环境等误差与变化的敏感,在平面闭链机构中都具有典型的意义。本论文在前人研究的基础上,利用新的数学方法和先进的数值仿真技术,对过约束机构及自调结构的分析与设计进行更深入、系统的研究、验证和工程应用实践。本文利用空间角度转换理论确定了机构形位误差对机构产生的影响程度,即影响度,并对其进行量化。分析方法相对于前人的方法来讲更加直观,简洁明了,避免了大量的矩阵运算,本文中的数学方法计算出的角度误差的表达方式更加简化,减少了由于运算带来的计算过程中误差的累计。并利用基于ADAMS的虚拟样机技术对曲柄摇杆机构中B铰链存在的4种单因素误差产生的影响度进行了实验验证,由实验结果分析验证了理论分析的正确性。为了分析铰链在存在形位误差的情形下铰链中接触应力的分布情况,利用ANSYS有限元分析工具,通过对B铰链存在的四种可能出现的形位误差造成在装配过程中产生的接触应力的分析,真实的反映了铰链接触应力的分布情况,从而由宏观的力分析进入微观的应力分析,这也是前人没有涉及过的。并结合工程实际,在对新型恒脉动机械式无级变速器主传动机构进行过约束分析的基础上,对该系统进行了消除或减小过约束及其影响的自调结构的创新设计,并在基于ADAMS的虚拟样机软件中进行了建模和仿真,将自调前后的机构进行了比较,在负载一定的情况下,对样机的输入功率及机架震动力进行了分析,分析结果表明,设计方法是正确的、有效的。本文的工作,丰富了机构结构设计理论,完善了自调结构设计理论,进一步推进了平面约束不确定性的影响分析及自调结构的分析、设计理论与方法的研究,以及自调机构系统的工程应用,具有普遍的指导意义和重要的应用价值。更多还原

【Abstract】 The design of mechanical and electrical production is to satisfy some special function, but these functions are often realized by the action of mechanism. Planar linkage mechanism is the most important one among the numerous mechanisms and can also be regarded as the theoretical structure model of all other basic mechanisms, thus the linkage mechanism is often researched at first in the process of the study of mechanical theory and methods. Planar linkage mechanisms are often obturated by lower.pair, so the constraint is also forcible. Its redundant structure and the sensitivity to the error of manufacturing, assembly error and environment, are very typical in planar linkage mechanism. Based on the research of other people, the new math method and advanced numerical simulating technology are used in this paper. The analysis and design of over.constraint mechanism and self.adjustable mechanism are more systemically researched, validated and applied in engineering practice.The degree of influence caused by the Fig.ure and position error to mechanism is confirmed and quantitated in this paper by the theory of spacial angles conversion. Compared to prevenient methods, the analysis method is more concise. It avoids abundant matrix calculation. The expression of angle error is more concise. The accumulation of calculation error is reduced. The virtual prototype technology(based on ADAMS) is used to validate the degree of influence. The four single errors exist in joint B in crank.rocker mechanism. The result indicates that the theory analysis is correct. In order to analyze the distribution of contact stress in joints, the ANSYS finite element tool is used. The situation of four single errors in joint B is analyzed. The distribution of contact stress is actually reflected. The microcosmic stress analysis is referred. In this paper, combined with engineering practice, by analyzing for over.constraints of transmission mechanism in a impulse variable speed device, the creative design of the mechanism was completed in order to eliminate or decrease the over.constraints in the mechanism. The ADAMS software is used to model and simulate. Compared the self.adjustable mechanism and former mechanism, the input power curve and vibration force curve is better than before. The analysis result indicates that the design method is correct and efficient.The work in this paper makes mechanical structure design theory more abundant. The self.adjustable structure design theory is more consummate. The analysis of更多还原