【作者】 韩丽丽；

【导师】 孙宝元；

【作者基本信息】 大连理工大学 ， 机械电子工程， 2006， 博士

【摘要】 钻削测力仪是研究钻削过程最基本的仪器和手段，通过测得钻削力的变化，人们能快速的识别故障，提高加工过程的可靠性和生产效率。因此钻削测力仪是现代自动化加工过程中实现状态监控、自适应控制和最优控制必不可少的环节。随着科学技术的发展，人们对钻削测力仪的功能和性能指标也提出更新更高的要求。 本文在国家自然科学基金(50475152)的资助下，从工程实际出发，在运用了晶体物理学、电介质物理学、压电学、各向异性材料力学、电磁学等交叉学科的理论成果的基础上，根据其特点与使用要求，对钻削测力仪结构中的关键尺寸和动态特性进行了设计和分析。设计制造出利用石英晶片扭转效应测扭矩，只采用四片石英晶片就可以同时测量钻削过程中的扭矩、轴向力、径向力的三向压电钻削测力仪。其测力范围为M_Z=0～9N．m，F_z=0～1500N，F_x=0～1000N。经过静态标定、动态标定和实际钻削测定，其各种指标都已达到设计要求。该三向压电钻削测力仪同其他钻削测力仪相比突出的特点是：它采用了石英晶片的扭转效应测扭矩，可以实现钻削过程的无定心测量；测扭矩和径向力的晶组仅由两片普通YO~0切型的石英晶片组成；其结构简洁、调试方便、加工与装配工艺性好、成本较低。同时检测钻削过程中的三向力，能更全面地反映钻削过程中钻削力的分布情况。 研制出了扭矩加载器，该加载器基于柔性铰链组成导杆，只需要加载一个力即会产生一个平衡对称的纯扭转，具有结构简单，制作方便的优点。柔性铰的尺寸参数和位置参数是该装置设计的关键，其参数的大小可通过有限元分析软件ANSYS进行结构优化得到。经过实验分析，确定其加载产生扭矩的范围为M=0～16.375N．m，加载器精度和转换率高，线性度和重复性好。 本论文还论述了压电效应的产生机理，并探讨了在机械扭矩载荷作用下正方形内带圆孔的压电晶片内部由弹性各向异性引起的复杂应力状态，结合各向异性扭转理论和各向异性麦克斯韦电磁理论，得出了YO~0切型的方形内带圆孔石英晶片扭转应力场和非线性极化体电荷与面电荷的密度分布规律，并采用有限元软件ANSYS模拟了应力场和极化电场在压电石英晶片内的分布。结果表明在晶片表面上扭转极化电荷密度分布是以电轴为分界线成对称分布，电荷正负相反，外扭矩与极化产生的电荷量之间是确定的线性关系。更多还原

【Abstract】 The drilling dynamometer is a fundamental device of researching the drilling process. By the change of drilling force in the process, people can detect a malfunction. So it is a necessary part of real-time monitoring, self-adapting, optimum control in the automatous machining process. With the development of technology, the functions and performances of the drilling dynamometer are under improvement.This project is funded by the National Natural Science Foundation of China (No. 50475152). From the application aspect of engineering, interdisciplinary knowledge, such as Physics of Crystals, Physics of Dielectrics, Piezoelectricity, Theory of Elasticity of an Anisotropic Body, Electromagnetics is utilized in the investigation on design and manufacture of the drilling dynamometer. On the basis of theory analysis, the key dimensions and dynamic characteristic of the drilling dynamometer are designed and analyzed according to its specialty and applied demand. Based on the torsion effect of the piezoelectric quartz slice, the three-component piezoelectric drilling dynamometer can measure a torque. It can also measure an axial force and a radial force though it is composed of only four slices of quartz. The measuring range is M_z =0 ~ 9 N.m , F_z =0 ~ 1500N, F_x =0 ~ 1000N. By the staticcalibration, the dynamic calibration and practical application, it is showed that the performances of the three-component piezoelectric drilling dynamometer are up to need. The outstanding feature of the three-component piezoelectric dynamometer in contrary to other types of drilling dynamometers is as follows: it adopts torsion effect of square quartz with a circular hole inside, which makes no-centering measuring of drilling process come true. Only two slices of Y0°-cut quartz are used in a torque and a radial force measuring. The structure is simple and convenient for checkout. The technical performances of machining and assembling are good, and its production cost is low. The dynamometer can measure three components forces at the same time; therefore, the distributing situation about cutting forces in drilling process is described more completely.A torque-loading device is designed and manufactured, which can load a pure torsion. Flexible hinges form guidance. Given a force, the torque-loading device can produce an equilibrated and symmetrical torsion. It gains advantages of simple structure and easy manufacture. Dimension parameters and location parameters of the flexible hinges are the key更多还原