【作者】 张青召；

【导师】 马胜钢；

【作者基本信息】 郑州大学 ， 机械制造及其自动化， 2012， 硕士

【摘要】 大型振动筛在提高处理能力、增加经济效益方面的优势明显,因此大型振动筛在工业各部门的应用越来越广泛,大型振动筛的研发成为一个重要的发展趋势。在研发时所要解决的关键问题之一即结构的强度分析与计算,准确地计算振动筛起动过程中的力学行为是关建中的关键。本论文对大型振动筛的起动过程进行了较深入分析和研究,得到振动筛上关键位置处的应力分布情况和变形规律,得出一些有益的结论,可为振动筛的结构设计和优化提供参考。本文首先以结构动力学为理论基础,结合直线振动筛的工况特点,建立起了偏心不平衡质量引起的强迫振动模型,进而建立起系统的振动微分方程。采用更符合实际工况的激振力载荷数据,利用MATLAB进行仿真计算,得到振动筛起动过程的一般运动规律。借助ANSYS软件建立起振动筛筛箱的有限元模型,并对建模过程中相关问题进行了讨论。利用ANSYS模态分析模块对筛箱进行模态分析,得出振动筛的前14阶固有频率和振型,结果表明其在工作频率下不会发生共振。通过MATLAB与ANSYS之间的数据通道,采用上述激振力数据,在ANSYS中对筛箱进行时间历程分析,得到了一些关键位置处的应力分布情况和变形规律：振动筛筛箱在共振时有明显的应力集中现象,而稳定工作时应力分布均匀；不论是在共振时还是正常工作时,横梁与侧板相接处的应力值均是最大值。这些都能够为振动筛的结构设计与优化提供理论依据。文章最后利用划分子结构、采用功率流的方法对子结构的结构强度进行分析,得出一些有益的结论。通过对比验证,本文所建立的振动筛筛箱的有限元模型较好地反映了筛箱实际结构和工况特点,满足了动力学分析的要求；本论文采用的激振力数据贴合实际,首次对振动筛的起动过程做了较详细的动力学分析,并在振动筛的振动分析和强度分析中尝试使用子结构划分法和功率流法,得到较好的效果。该研究成果不仅可以为振动筛研发过程中的计算分析提供参考依据,而且也为振动筛或者其他振动结构的振动分析和强度分析提供了一个很好的方法。更多还原

【Abstract】 Large vibrating screens have many advantages, including of increasing treatment capacity, improving economic efficiency, which make large vibrating screens widely applied in the industry and the study about large vibrating screens develop rapidly. The analysis and calculation of structural strength is one of the key problems in the study, and calculation of the mechanical behavior during the starting process of the vibrating screens is the.most key problem. The starting process of large vibrating screens was analyzed and studied in-depth according to above problems. The stress distribution and deformation law of vibrating screens’parts was got, some useful conclusions was draw, which offer references for structural design and optimization of vibrating screen.In this paper, firstly forced vibration model caused by the eccentric mass was built, based on structural dynamics and the work characteristics of liner vibrating screen, and then the vibration differential equations of system are established by d’alambert’s principle. The exciting force loading data which is more suitable to the actual conditions was estimated, and the general motion law of the starting process of vibrating screen was obtained through simulating with MATLAB.The finite element model of the screen box of vibration screen through ANSYS, and some related problems in the modeling were discussed. The screen box was analyzed through modal analysis module, and the first14natural frequencies and vibration modes were got, and the result shows that the structure doesn’t have sympathetic vibration under steady state.The time-dependent analysis of the screen box was made with above exciting force data through data channel between MATLAB and ANSYS, and the stress distribution and deformation law of screens box was got:there are stress concentration during resonance, and stress was well-distribution under steady state; the stress of the junction of the beam and side plates was biggest, which can offer references for structural design and optimization of vibrating screen.In the end of this paper, I tried to use the method of substructure-divided and power flow to analyze the strength of substructures, and obtained useful conclusions. The comparison results showed that, the established finite element model of screen box of vibrating screen reflects better the actual structure of screen box, and satisfied the requirements of the dynamic analysis; The exciting force data in this paper was more suitable to the actual conditions, and for the first time the dynamic analysis of the starting process of vibrating screen was made, and tried to use substructure-divided method and power flow method, and successful effect was got. The research results not only can offer references for calculation analysis during the develop process of vibrating screen, but also provide a good method for the vibration analysis and strength analysis of the vibrating screen and other vibrating machines.更多还原