共查询到19条相似文献,搜索用时 156 毫秒
1.
2.
3.
4.
5.
6.
7.
PCB微钻有限元分析的几个关键问题 总被引:1,自引:0,他引:1
随着印制板和封装技术的快速发展,印制板钻孔面临越来越大的挑战。钻孔质量受钻机、钻头、钻削参数和印制板材的影响,文章对微钻有限元分析的几个关键问题进行探讨,以提高微钻设计水平。首先评述了微钻有限元分析的研究现状,然后讨论了微钻三维模型的建模方法,最后对微钻设计中的几个重要参数对微钻性能的影响进行了重点分析。文章的主要创新点包括:(1)提出了通过CAD方法建立微钻三维模型的方法,保证了有限元分析的精度;(2)分析了微钻参数对微钻性能的影响,该结果可以指导实际的微钻设计。 相似文献
8.
超声切割刀在材料加工领域中有广泛的应用前景,可用于切割各种复合材料等硬脆材料。该文利用ANSYS有限元分析软件建立超声切割刀的有限元模型,对其进行模态分析和谐响应分析。仿真结果显示,超声切割刀在40 kHz频率附近存在轴向纵振模态,其振动节点位于安装环和压电陶瓷中心线上,符合设计要求。基于有限元模型研制超声波切割刀,通过阻抗分析仪与激光多谱勒测振仪对换能器的固有频率与响应进行测试,获得的超声切割刀阻抗曲线平滑,谐振频率为40.261 kHz,设计误差为0.83%,最大振幅达到14.52 μm,结果与有限元计算相互吻合。 相似文献
9.
超声切割刀在材料加工领域中有广泛的应用前景,可用于切割各种复合材料等硬脆材料。该文利用ANSYS有限元分析软件建立超声切割刀的有限元模型,对其进行模态分析和谐响应分析。仿真结果显示,超声切割刀在40kHz频率附近存在轴向纵振模态,其振动节点位于安装环和压电陶瓷中心线上,符合设计要求。基于有限元模型研制超声波切割刀,通过阻抗分析仪与激光多谱勒测振仪对换能器的固有频率与响应进行测试,获得的超声切割刀阻抗曲线平滑,谐振频率为40.261kHz,设计误差为0.83%,最大振幅达到14.52μm,结果与有限元计算相互吻合。 相似文献
10.
针对常见的超声振动系统难以满足体内碎石对小体积和大振幅的要求,对小体积实现大振幅的超声振动系统的设计原理和方法进行研究。根据任意截面杆的波动方程,得到单一截面杆的位移方程和应力方程,并通过振动系统的边界条件,推导出超声振动系统的频率方程。根据推导出的频率方程,设计出用于碎石的超声振动系统,对所设计的超声振动系统振动性能进行有限元分析和试验测试,分析和试验结果表明,振动系统谐振频率的设计结果和有限元分析及测试结果的误差均在3%以内,测得碎石振动系统的振幅为25μm。 相似文献
11.
工程陶瓷的旋转超声加工方法 总被引:4,自引:0,他引:4
旋转超声加工是加工工程陶瓷的一种有效方法,它与传统的加工方法相比具有加工速度快、加工精度高、加工质量好、工具头磨损小等特点.旋转超声加工已成为加工硬脆材料的主要方法之一.介绍了该加工技术的基本原理、应用特点、关键技术以及旋转超声加工的应用范围和发展趋势. 相似文献
12.
数控机床加工零件,通常在零件加工后采用另外的仪器进行加工误差测量,重复装夹必然造成精度降低和工时延长.数控机床通过控制走刀路径使其按照特定轨迹运动,因此工件的加工误差可通过测量轨迹误差得到.文中运用非均匀B样条曲线拟合及曲线特征点提取的方法,将测量轨迹与理想轨迹进行拟合实现工件加工误差的在机测量.通过在数控机床上试验一直线圆弧样品加工验证了该方法的可行性. 相似文献
13.
《Mechatronics》2015
Milling force is an important parameter to describe the mechanical processing chip removal process, and it has a direct influence on generation of heat, tool wear or failure, quality of machined surface and accuracy of the work piece. Its accurate measurement is a significant basis for judging process state and improving the reliability of machining system. In this study, through analyzing the variation rule of ring diameter, a new method that using Fiber Bragg grating sensors and variation rule of ring diameter to measure the milling force has been proposed, and the basic structure of annulus has also been designed. A dynamometer has also been constructed, and the preliminary verification test was done. Through the analysis of experimental data, the dynamometer based on annulus elastic body can be used in milling force test, and it owns high sensitivity. 相似文献
14.
Tool breakage monitoring using motor current signals for machine tools with linear motors 总被引:2,自引:0,他引:2
Xiaoli Li Du R. Denkena B. Imiela J. 《Industrial Electronics, IEEE Transactions on》2005,52(5):1403-1408
In recent years, a number of machining centers have been built using linear motors. These machining centers have great potential for precision and high-speed machining. Nevertheless, a number of problems remain unsolved, such as monitoring and control. This paper presents a new tool breakage monitoring method for this type of machining center using the current signal of the linear motor. First, the relationship between the cutting force and the motor current is analyzed. Then, the new tool breakage method is presented. From a mathematical point of view, the new method uses a nonlinear energy operator to capture the abrupt changes of the motor current signal, which is directly related to the tool breakage. The experiment validation is included. 相似文献
15.
《Mechatronics》2003,13(8-9):825-849
An intelligent supervisory system supported on a model-based approach is presented herein. The application for predicting tool wear in machining processes is selected as a case study. A model created using artificial neural networks and able to predict the process output is introduced as a means of dealing with the characteristics of such an ill-defined process as machining. This model describes the output’s dynamic response to changes in the process-input command (feed rate) and process parameters (depth of cut). In order to predict tool wear, residual errors are used as the basis for a decision-making algorithm. Based on the model and the weighted sum of squared residuals method, the procedure continuously checks whether a given index (tool condition) exceeds a critical threshold. In the chosen application, an over-the-threshold index is interpreted as indicating unacceptable tool wear necessitating immediate tool replacement. Experimental tests are run in a professional machining centre under different cutting conditions using real-time data and new, half-worn and worn tools. The results show this supervisory system’s suitability and potential for industrial applications. 相似文献
16.
17.
本文概要介绍超声旋转加工原理、特点和T30303/ZV型超声旋转加工机。验证了具有细长金刚石钻头的超声振动系统可按“局部共振”设计和调谐,观测了超声旋转加工对加工材料性能的影响,测量了加工精度,得出超声旋转加工能有效用于Nd:YAG晶体棒外圆成形。 相似文献
18.
19.
差动往复式线性超声马达的研究及应用 总被引:1,自引:1,他引:1
研制了一种新型的双定子驱动的差动往复式线性超声马达,提出了分组脉冲驱动控制方法,分析了其工作过程,实现了差动往复式线性超声马达的单向步进式进给及双向差动往复式进给,移动体的进给量与运动方向由每组的驱动脉冲数确定。研制的样机在电火花加工中得到了应用。 相似文献