电火花机床伺服性能研究

本文对机床伺服性能进行了系统的测试与分析,推出了一个较能适应电火花超精加工的机床伺服控制系统.     

从CIMT2013看金属成形(锻压)机床新发展——CIMT2013第十三届中国国际机床展锻压展品述评

1 CIMT2013概况 2013年4月22 ～27日,为期6天的第十三届中国国际机床展览会(CIMT2013)在北京中国国际展览中心(新馆)成功举办. 本届CIMT2013展会展出面积达12.6万平方米,创历届规模之最.包括世界知名机床制造业百强企业在内的28个国家和地区的1500余家机床工具制造厂商汇聚北京.其中,境内展商800多家,境外展商700多家,展出面积境内、境外各占50％左右.展品主要包括1200多台国内外较高水平的机床主机产品和大型量仪及数万件机床配套产品. 2 金属成形(锻压)机床展品 2.1数控激光切割机 数控激光切割机依然是金属成形机床展品中数量最多的展品,总数超过30台套.其中,光纤激光切割机从面世之初的星星之火发展为如今的燎原之势,仅仅用了3年左右的时间,再次证明了新技术在现代工业发展进程中的强劲推动力.     

从CIMT2003看数控激光切割机的发展

分析了第八届中国国际机床展览会(CIMT2003)上的数控激光切割机展品，介绍了日本AMADA、德国TRUMPF、济南捷迈数控机械公司等的数控激光切割机展品，探索了数控激光切割机的技术水平现状和发展趋势。     

基于Startup TOOL的840DSL驱动系统优化

为了使机床的伺服参数与机械性能达到最佳匹配,通过对机床伺服参数进行优化调节,提高了机床的动态特性和加工精度。针对840DSL的SINAMICS驱动系统,利用Startup-Tool工具及系统自带的优化功能对伺服参数进行手动优化,通过频率响应、阶跃响应、参考模型、前馈、TRACE、圆测试等实现速度环和位置环的优化,提高了机床的加工精度和伺服性能。     

DS-054数控激光切割机的可靠性及经济效果

DS-054数控激光切割机床是具有现代技术水平的切割机床,自在我厂使用以来,在客车的研制和生产中发挥了积极的作用,取得了较明显的技术经济效益。可靠性是激光切割机在使用中的重要指标,也是评定该机床设计和制造质量的主要指     

济南铸锻所有限公司先进产品获关注

正近日,中国国际金属成形展览会在北京国际展览中心举办。济南铸锻所有限公司携FL513 i光纤激光切割机和SPH21250DT高端数控伺服转塔冲床参展。FL513 i光纤激光切割机可对激光焦点实现自动调节,此功能极大减少了打孔时反射激光对激光器的损伤,同时高压气体的调整具有准确、迅速的特点。与同类产品对比,以上优势提高了该设备的稳定性、可靠性,同时送进速度快、工作效     

济南铸锻所LR0412高性能宽幅面地轨式数控激光切割机

正LRO412高性能宽幅面地轨式数控激光切割机是济南铸造锻压机械研究所有限公司2009年研发的最新型机床,是本所继1985年生产出全国首台激光切割机以来,通过二十多年的不懈努力、不断追求,在销售数百台激光加工机     

CAD／CAM编程排料软件助钣金制造业提高竞争力

当前钣金制造业的现状 随着钣金制造企业的生产规模逐渐扩大，所引进的各类数控钣金加工机床也越来越多，一般情况下这意味着，钣金厂拥有多种加工类型的机床，包括激光切割机、数控冲床、水射流切割、复合机、等离子切割机等。机床分别来自不同的制造商，呈现出机床品牌多样化的特点。编程软件多样化，不同机床采用完全不同的编程软件。     

基于PLC的切割机运动轨迹控制系统的设计

在实际应用中,很多切割机不能满足加工精度要求,精度高的切割机又十分紧缺,因此发展高精度的切割机很有必要。另一方面,很多切割机自动化水平不高,尤其是手动操作的切割机在操作时很不方便。故采用可编程终端、PLC、运动控制单元、伺服驱动系统等成熟的控制部件构建切割机运动轨迹控制系统。详细设计此系统的各个模块单元,介绍各个部件之间的数据通信和软件设计步骤,并以一个简单的例子说明了其操作过程。采用此运动系统能使加工工件的质量、机床的自动化程度、可操作性都得到大幅度的提高。     

数控激光切割机伺服进给系统的机电耦合建模与仿真分析

以数控激光切割机伺服进给系统为研究对象,通过分析系统各环节的数学模型,得到了系统的动态结构图,建立了进给系统的机电耦合模型,仿真分析了系统传动刚度对伺服系统的影响。利用该机电耦合模型可以分析系统参数对伺服系统动态特性的影响,对系统动态性能进行优化,提升伺服进给系统的设计效率。     

伦茨交流伺服系统在钢板横剪中位置全闭环的应用

在卷材横剪机组中,定尺送料控制系统是非常重要的组成部分。本文以钢板横剪机组为例,针对定尺控制的工艺要求,提出了伦茨（LENZE）伺服控制系统位置型全闭环应用的方案。实践证明,这些方案是可行的,并可靠地应用在大量的卷材横剪机组中。     

Proposal of ‘ImpEC (impact excitation cutting)’ for realization of high-flexibility and high-efficiency micro/nano surface texturing

In this paper, a novel micro/nano surface texturing method, namely ‘ImpEC (impact excitation cutting)’, is proposed. To machine micro/nano-textures, vibration cutting and fast tool servo have been utilized. However, the former one is limited to formation of periodical combination of sine waves since the resonance(s) of the cutting tool system is used, and the latter one is limited in terms of efficiency since it has conventionally been utilized within the bandwidth of the servo system, e.g. 3 kHz. Hence, conventional methods cannot realize high flexibility and high efficiency simultaneously. In the proposed ImpEC (impact excitation cutting), the frequencies higher than the resonant frequency are also used, and a series of impacts (pulses) are utilized to diminish the residual vibration. The proposed cutting method can create structures in a short time since the high frequency components are also used, and it can also realize high flexibility since a variety of texturing motions without residual vibrations can be triggered at any timing. The effectiveness of the proposed method is verified both analytically and experimentally.     

Feed drive control tuning considering machine dynamics and chatter stability

In large machine tools, where structural dynamics significantly influences the cutting stability, judicious selection of the servo control parameters can increase the damping, thereby improving the chatter stability. This paper presents a new strategy for feed drive controller tuning, which takes this effect into consideration. The proposed strategy generalizes successfully to machine tool structures with high order dynamics, and integrates model-free frequency domain estimation and analysis techniques with model-based root locus design, the latter which is achieved through an efficient and accurate identification approach. The proposed strategy has been tested in machining stability tests, demonstrating up to 30% increase in productivity.     

Tracking and contour error control in CNC servo systems

The dynamic response of a machine tool is a complex interaction of several factors that includes the basic design of the machine as well as the capability and performance of the corresponding axis servo system. In terms of the performance of the servo system, tracking and contour errors are two important aspects that significantly affect the machine tool. Extensive research has been conducted over the last several decades into the study of these error components. A number of different approaches have been proposed by various researchers that attempt to effectively address this problem. This paper attempts to study the work that has been carried out in minimising tracking and contour errors in CNC machine tools.     

Influence of guideway friction on the cutting point receptance in machine tools

Motivated by the fact that the tool cutting point (TCP) receptance demonstrates significant variation between the idle and in-motion conditions of a machine tool, this paper studies the relationship between guideway friction and TCP dynamics. The fundamental effect is modelled and demonstrated on a laboratory testbench considering structural mechanics, servo dynamics, and guideway friction. The findings are then extended to an industrial-scale machine, for which improved measurement of the TCP receptance is obtained using a dedicated inertial linear actuator. Finally, practical in-motion impact hammer testing guidelines are proposed for more accurate characterization of the TCP receptance and chatter stability predictions.     

HRB500高强度钢筋剥肋倒角装置设计与研究

针对传统加工方式会损伤大直径HRB500高强度钢筋强度性能等问题,考虑加工要求及形状特点,设计能够完成铣端面、剥肋、倒角的剥肋倒角机整体结构和加工工艺。根据高强钢筋材料的性能,选定刀具具体参数,确定复合刀具的加工工艺参数。设计钢筋轴向定位夹紧装置,并对夹紧力进行计算。采用以伺服电机作为动力源的传动系统,进行传动系统的主要参数计算和电机的计算与选型。利用ANSYS软件进行切削过程的有限元分析,获得了切削过程中刀具的应力变化曲线及其应力变化云图。实验结果表明：所设计钢筋剥肋倒角机可应用于高强度钢筋加工领域,并且切削效果良好,能够很好地适用于各个工序。     

Simulation of the main cutting force in Crankshaft turn broaching

The measurement of the cutting forces of a turn-broaching machine is very complex due to the relative movement between workpiece and tool. In this work the cutting forces were simulated through the modeling of the process kinematics and by applying the Kienzle equation. A new experimental approach was proposed to determine the cutting forces using a conventional CNC turning machine tool. Through a series of experiments, the model has been calibrated. A comparison between the numerical and experimental results showed a similar trend. The effect of maximum cutting depth, workpiece diameter, cutting edge inclination angle, and feed rate on the main cutting force has been studied.     

Performance robustness and stiffness analysis on a machine tool servo design

The machine tool servo design is very different from the traditional high performance servo systems. Traditional servo design depends heavily on a precise system model so that frequency domain or time domain compensation techniques can be applied, and many synthesis tools such as LQG, H_∞, or LMI, … are available based on this concept. While these synthesis tools are becoming very useful in many situations, they are not used in the machine tool servo design. Most high performance machine tool systems still rely on the more primitive PID or PDF controllers in conjunction with complicated friction and temperature compensation algorithms. This paper investigates the different approaches based on a house-designed servo control board. With the ability to change the servo control algorithms on a test machine tool, the performance robustness and servo stiffness were tested both numerically and experimentally. The numerical tests conducted with PID, PDF, and LQG controllers showed that the PID controller is the easiest to achieve good performance, but the PDF controller contains the best performance robust margin. Experimental results also indicated that the PDF controller exhibits far superior robustness properties over the other two controllers.     

伺服系统HRV控制对数控机床加工精度影响的研究

为了提高数控机床的定位、加工面和加工形状精度,缩短加工时间,提出了伺服系统HRV控制方法。阐述了数控系统伺服HRV控制的原理、作用和伺服HRV控制设定的方法。该HRV控制法大大提高了伺服各环节性能,从而提高了系统的控制精度。     

基于误差相关性分析的复合伺服控制器设计

由于伺服系统控制精度对超精密机床性能具有很大影响,伺服系统控制器方案需要根据实际应用的需求进行设计;而位置跟踪误差是机床伺服系统的主要评价标准之一.本文根据实测数据,提出了基于相关性分析的位置伺服控制器改进方案,对跟踪误差与速度、加速度等进行相关性分析,设计了具有速度、加速度前馈补偿的复合控制器.通过对补偿前后系统响应的实验数据进行比较,可以看出进给伺服系统的控制精度显著提高,有效减少了跟踪误差.