【作者】 毛君；

【导师】 李贵轩；

【作者基本信息】 辽宁工程技术大学 ， 工程力学， 2006， 博士

【摘要】 本文总览了刮板输送机理论研究的现状,分析了现有研究的不足。分析了刮板输送机链条纵向振动的特点并进行适当简化,推导出纵向振动的基本方程,考虑驱动性能差异确定了不同工况下的边值及初始条件。构造了振动方程的标准形式,得出了特定情况下的解析解。研究了刮板输送机振动力学有限元模型的构造方法,分析了影响因素,在考虑链条的非线性特征、溜槽的弹性以及溜槽间隙、物料的物理特性、刮板的扭转、自动张紧系统作用等因素的情况下,构造了4种动力有限元模型并导出相应的振动微分方程;研究了刮板推移物料的力学问题;导出了保持物料稳定运行的刮板间距以及推力计算式;研究了在无载侧形成料栓时刮板的推力以及刮板输送机的运行阻力,以运行阻力最小为目标优化刮板间距,结果与目前工程设计值基本一致;为便于建立仿真数据库,研究了常用驱动装置的特性,构造了动力学模型,建立了数学模型;分析了水平弯曲段处的受力和链条的张力差;推导出溜槽单元体摩擦阻力的计算式以及链轮与链条啮合角的计算式;在考虑链环间弹性接触问题的情况下,推导出链条的弹性伸长、刚度与拉力的关系,证明了其刚度具有非线性特征。研究了动力仿真模型的构造方法,设计了一个能够描述输送机线路特征的形态函数,实现了动力仿真的自动建模;提出了对故障及异常载荷的模拟方法,开发了仿真软件,对刮板输送机的起动、制动、卡链、断链、链轮有限齿数波动链条产生的冲击(又称多边形效应)、链条节距误差等不同工况下进行了数值仿真,根据仿真结果分析了各种工况下不同因素对动载荷的影响。研究了刮板输送机动态特性的控制理论及方法,对刮板输送机的起制动特性进行了研究,理论研究和仿真结果证明了控制起动速度可行,且按反“S”曲线起动最优;研究了以动载荷最小为目标函数的输送机主参数的匹配优化问题,运用振动与控制工程的理论推导出动态优化设计的目标函数和约束条件,并提出了便于工程应用的无共振设计方法;分析了刮板输送机链条预紧力对工作性能的影响,提出了刮板输送机链条预紧力的自动控制原理,设计了用电液比例阀或电液伺服阀控制的液压系统,研究其控制理论,推导出控制系统的传递函数,将模糊PID控制器引入到该系统的控制中,通过实例仿真证明了这种预紧力控制系统和控制方法具有很好的响应和稳定性。实测了双速电动机直接起动的头尾双驱动输送机在起动、自动停机以及稳定运行更多还原

【Abstract】 This paper has given a overview of the actuality about reseach on scraper conveyer theory, and it has analyzed the deficiency about the research in existence.This paper has analyzed the longitudinal oscillation characteristics of scraper conveyer chain and carried on the suitable simplification. It has deduced the fundamental equation of longitudinal oscillation. Considering the actuation performance difference, it has determined the boundary values and initial conditions under different operating modes. It also has constructed the standard form of vibration equation, and obtained its analytic solution in the specific situation.This paper has studied the structure method of scraper conveyer vibration mechanics finite element model, and analyzed the influence factors. Considering the non-linear characteristics of the chain, the elasticity of downspouting as well as the downspouting gap, the material physical properties, the scraper twist, the function of automatic tightening system, it has constructed 4 kind of dynamic finite element models and deduced the corresponding vibration differential equations. It has studied the mechanics question of the scraper when processing material. It has derived the scrapers spacing to maintenance material stable movement as well as the thrust caculating formula. It has studied the scraper thrust and the movement resistance of scraper conveyer when material hitch formed on the no-load side. Taking the minimum operating resistance as the goal to optimize the scrapers spacing, the results are consistent with the present engineering design values in the rough. In order to be advantageous for the establishment of simulation database, it has studied the characteristics of commonly used driving devices, constructed the dynamics models, established the mathematical models, analyzed the stress and tension difference of chain in level curving section, and deduced the friction drag mathematical formula of downspouting unit and the mathematical formula of meshing angle between chain wheel and the chain. Considering the spring contact question of chain links, it has deduced the relations of the elastic elongation, the rigidity and the pulling force of chain. It has proven the non-linear characteristic of its rigidity.更多还原