【作者】 王洋；

【导师】 原所先；

【作者基本信息】 东北大学 ， 机械工程， 2013， 硕士

【摘要】 砂带磨削工艺是种又古老而又新兴的机械加工工艺。发展了30多年,随着黏满不规则砂粒的砂纸、砂布研制成一种高速、多刀多刃连续切削的磨削工具应用在砂带磨床中,砂带磨削技术突飞猛进。过去我们只用砂带加工和抛光的陈旧概念已被新兴的砂带磨削技术彻底改变了,其加工的效率基本已经超越了刨、铣、车等较为传统的加工工艺,而砂带磨削加工精度已接近,有的甚至已达到传统加工机床水平,砂带磨削的功率利用率,已经能够高于一切金属切削机床,它的应用范围很大,不仅遍及各个加工行业,且能加工几乎所有的材料,包括金属、非金属都在加工范围之内,砂带磨削工艺现在以高速度发展。机械结构中大量存在着不同类型的结合面,这些结合面的存在使机械结构、机械系统不会再具有连续性,使问题的研究变得复杂。接触刚度、接触阻尼存在于结合面中。文献指出,机床结构中结合部的阻尼、弹性,尤其是阻尼,般比结构本身的阻尼、弹性还要大。所以设备结构总柔度、总阻尼中包含着很多的结合部的柔度和阻尼,研究表明,所有大型机械设备中,结合面接触阻尼约占有总阻尼的90%。机床总刚度不足的60-80%是结合面的总刚度不足造成的。正是因为机床结合面的性能对于机床整机的动态性能很重要。所以人们研究机械结构整体的动态特性设计研发时,就得考虑结合部的影响。论文首先建立了钢板砂带磨抛机和结合部的等效动力学模型,还分析了常用的结合面等效动力学参数的识别、结合面仿真方法,提出利用弹簧阻尼单元模拟法、接触法,这些方式对实际结合面的动态特性进行研究。运用三维建模软件Pro/E、有限元分析软件ANSYS建立了砂带磨抛机的有限元模型,考虑结合面的影响,对机床整机进行了模态分析,对钢板砂带磨抛机的框架结构进行了静态和动态拓扑优化分析,通过分析找到上板和基座的薄弱环节,考查了由上板、基座、立柱所构成的框架结构对动态特性影响趋势,明确了上板、基座的改进方向,改进使机床的整机性能得到了提高。粗糙平面接触仿真识别结合面接触刚度,首先必须对材料表面粗糙情况进行数值模拟,这是表面的接触刚度特性研究中的基础和关键。实现方式是利用轮廓的算术平均偏差评定方式,在取样长度内,取轮廓偏距的绝对值算术平均值来形成凹凸峰,并取特殊的等腰三角形,考虑形状误差的影响,生成特定粗糙度粗糙曲面,并进行接触刚度仿真模拟,刻画出不同压力下的法向接触刚度,分析微观凹凸峰弹塑性对接触刚度的影响并与吉村允孝实验刚度曲线进行对比。更多还原

【Abstract】 Abrasive belt grinding is a kind of old and emerging technology. Over the past30years,emery cloth and sand paper with sharp sand is made to a high-speed, multiple-point tool and it is used on the grinding machine,belt grinding technology gained great development. The belt grinding technology is far beyond the original use for processing and polishing. Efficiency of abrasive belt grinding processing is even more than the conventional process of lathing, milling, planning.The accuracy has approached or reached the level of the same types of machine tools,the power and use ratio machine is higher than other metal cutting machine tools, the range of application is throughout each industry, and for almost all of the material, either metal or non-metal can be processed,the belt grinding process which is belittled is now entering a new stage of modern development.Firstly, this paper builds the equivalent dynamic model of the grinder joint surfaces, and analyzes the usual parameter identification methods of the equivalent dynamic model of joint surfaces.Then Masataka Yoshimura method and Contact method are used in identifying nomal dynamic characteristics of the actual joint surfaces.At last,These coefficients are used to serve the spring-damp elements in modeling the joint surfaces of two parts.Most parts are using bolted joints in the grinder.Accurate finite element method analysis models are built by Pro/E and ANSYS. At the base of that and considering of the influence of joint surfaces,this paper will make modal analysis,static and dynamic topological optimization analysis of the grinder.The frame structure which consists of the upper plate,the base and the columns is analyzed to develop the mainly weak links of the machine.Some ideas of structural optimization are presented to develop the dynamic character of the grinder. Simulation of rough contact to identify the normal contact stiffness of joint surface:The numerical simulation on the material surface roughness condition is carried on.It is foundation and the key of the contact surface stiffness characteristic research. In the sampling length for contour offset arithmetic average of the absolute value is to form a concave and convex peak, and to take special isosceles triangle, specific roughness of rough surface is strictly generated to impose a particular waviness and contact stiffness simulation, It portrays the normal contact stiffness under different pressure to analyze the influence of the elastoplasticity to the normal contact stiffness.And Masataka Yoshimura experiment data is used to compare.更多还原