【作者】 张吉鑫；

【导师】 秦红斌；

【作者基本信息】 武汉理工大学 ， 机械工程， 2017， 硕士

【摘要】 汽车玻璃作为汽车的重要零部件之一,其安装质量对整车性能具有极其重大的影响,而定位销是汽车玻璃安装到车身上的定位机构,其重要性不言而喻。目前,国内企业定位销的装配都是采用刚性工装夹具来完成的,仅适用于在某一具体型号的汽车玻璃上安装定位销。随着汽车市场的竞争越来越激烈以及汽车玻璃规格型号的不断增多,刚性工装夹具已无法满足当前的发展需求。为此,本文研发了一款用于汽车玻璃定位销装配的柔性工装夹具,该工装夹具不仅满足多种型号汽车玻璃定位销的装配,还可提高定位销的装配精度。本文的主要研究工作如下:第一,完成了柔性工装夹具的总体方案设计和详细结构设计及分析。基于SolidWorks软件对柔性工装夹具中的自动对中夹紧机构、支承式真空吸盘机构、y向定位机构、y向夹紧机构和定位销装配机构等关键机构进行了详细结构设计和建模,并使用Workbench软件对关键机构进行静力学分析,完成了各机构的强度和刚度校核。同时,研发了一种新型的真空吸盘机构——支承式真空吸盘机构,可将定位支承和吸附固定功能集于一体,提高了工装夹具的可靠性和工作效率。第二,对柔性工装夹具中的关键夹紧装置即自动对中夹紧机构进行了优化设计。基于运动学分析,建立了自动对中夹紧机构的优化数学模型,使用ADAMS软件进行了优化分析和求解,并将结果应用于优化该机构的结构尺寸,提高其运动性能。第三,对柔性工装夹具中定位和夹紧元件的布局进行了优化设计。建立了该柔性工装夹具布局优化模型,结合遗传算法和有限元法,求解出使汽车玻璃变形最小的最优夹具布局。并利用Workbench软件分析优化前后汽车玻璃的受力和变形情况,验证了优化效果。优化后的最优夹具布局将用于指导柔性工装夹具的装配和调试。最后,对汽车后挡风玻璃进行了定位销的装配试验,并使用相应汽车玻璃的检具检测定位销的安装位置精度,试验结果表明柔性工装夹具能够很好地满足实际工程要求。本文研发的柔性工装夹具不仅能满足企业实际生产需求,而且对于其他薄壁零件柔性工装夹具的相关研究具有一定的参考价值。更多还原

【Abstract】 Automotive glass is one of the most important parts of the car,whose installation quality has great influence on the vehicle performance.Meanwhile,positioning pin appears particularly significant as the fixed device of automotive glass.At present,the assembly of positioning pin is mostly completed by rigid fixture in the domestic enterprise,which only suits for a specific model of the automotive glass.With the increasingly fierce competition in the automotive market and the increasing number of automotive glass specifications,rigid fixture has been unable to meet the current development needs.In order to solve this problem,this paper developed a flexible fixture for the assembly of positioning pins,which not only completes the assembly of positioning pins concerning various types of automotive glass,but also improve the positioning accuracy of the positioning pin.The main contents are as follows.Firstly,the overall design and detailed structure design of the flexible fixture were completed.Then,the key mechanism of flexible fixture was designed and modeled through SolidWorks software,which mainly contained automatic centering clamping mechanism,supporting vacuum chuck mechanism,orientation institutions along y axis,clamping mechanism along y axis and a positioning pin assembly mechanism.Afterwards,aiming to check the strength and stiffness,the statics analysis was carried out by Workbench software.Meanwhile,develop a new type of vacuum chuck mechanism,which integrated the positioning support and adsorptive fixation,improving the reliability and efficiency of the fixture.Secondly,the design of the key clamping device in the flexible fixture were optimized.Based on the kinematics analysis,the optimization mathematical model of automatic centering and clamping mechanism was established,which uses ADAMS software to optimize analysis and solution.Whose results would be applied to optimize the structure size of the mechanism to improve the dynamic performance.Thirdly,the layout of the positioning and clamping elements in the flexible fixture was optimized.Then the flexible fixture layout optimization based on genetic algorithm and finite element method,was set up to get the optimization layout,in which the deformation of the automotive glass is less.Afterwards,contrasting the stress and deformation of the optimal glass and before by Workbench.The optimizedfixture layout will be used to guide the assembly and debugging of flexible fixture.Finally,the assembly experiment of positioning pin on the windshield of the car is conducted,using the corresponding device to detect installation accuracy.And the results show that the flexible fixture can well meet the actual engineering requirements.The flexible fixture designed in the paper not only meet the actual production needs of enterprises,but also have some reference value for other thin-walled parts flexible fixture.更多还原