加速发展数控机床功能部件推动数控机床产业化

数控系统、电主轴和高速精密主轴单元、刀库和机械手、数控刀架、数控转台、滚珠丝杠副、直线电机等功能部件和电、液、气配套元件是数控机床的重要组成部分,是发展数控机床的基础。提升我国数控机床产业化水平,功能部件必须要进一步加快发展,夯实我国数控机床的基础。进入21世纪,我国数控机床取得了快速发展,2002年数控金属切削机床产量达24803台,比2001年同比增长了31.6％。数控机床的可供品种超过了1000种,掌握了代表     

Speed sensorless model predictive current control of doubly-fed induction machine drive using model reference adaptive system

This paper presents a speed sensorless control scheme named as finite control set-model predictive current control (FCS-MPCC) using a modified fictitious ohmic quantity (R) based model reference adaptive system (MRAS) for grid-connected doubly-fed induction machine (DFIM) drive. The variables of the reference model of this speed sensorless scheme (R-MRAS) are represented in stationary reference frame while those for the adaptive model are denoted in synchronously rotating reference frame. The sensorless formulation thus obtained is completely independent of any stator/rotor resistance terms. The scheme is also devoid of any stator/rotor flux estimation. Moreover, the intuitiveness of FCS-MPCC brings in additional flexibility in comparison to the conventional control techniques like field oriented control (FOC) and direct torque control (DTC). The overall scheme demonstrates faster execution time than FOC/DTC based control of DFIM drive. The proposed control algorithm is simulated and tested for limited speed range application in MATLAB/Simulink. The validation of simulation results are further done by experimentation on a dSPACE-1103 based DFIM laboratory setup.     

低速所缸与高速气缸

对气缸能达到最低无爬行状态的速度和高速运动时的最高速度进行了分析。     

高速数控技术的发展及其应用

数控技术的应用给传统制造业带来了革命性的变化,使制造业成为工业化的象征。随着数控技术的不断发展和应用领域的扩大,高速、高精度数控加工技术可极大地提高效率,提高产品质量,缩短生产周期并提高市场竞争能力。     

Auto-calibration of an SMT machine by machine vision

An SMT machine has many working coordinate frames—the fiducial mark camera frame, component camera frame, machine table frame, PCB frame, and reference frame. Because of many influences such as mechanical dimension errors, machine assembling errors, and camera lens distortions, all frames on the SMT machine must be calibrated to compensate for these machine errors. This paper applies machine vision techniques to auto-calibrate an SMT machine, including frame transformations and nozzle compensation, bringing the accuracy of this system to within ±0.1 mm. The coordinate mapping from the camera frame to machine table frame is a quadratic form, while the other frame mappings use linear forms. The merits for this machines vision-based, auto-calibration methods are: (1) It has little calibration time, (2) It does not need expensive calibration instruments, and (3) Its expense is very low.     

以橡胶压力成型机为主体的压剪实验机改造

介绍以橡胶压力成型机(硫化机)为主体,在保留原有橡胶加工功能基础上,增加横剪和压转的实验装置,改造成为多用途压剪实验机的方法。改造后设备可用于公路及铁路的桥梁橡胶支座成品及橡胶件综合力学性能检验。改造后设备操作便捷,精度和稳定性均可较好地满足使用要求。     

基于机器视觉的机械零件测量技术

应用IMAQ Vision软件构建的机械零件测量系统将机器视觉技术和虚拟仪器技术结合在一起，对各种机械零件进行快速准确的在线测量。这里以齿轮为例介绍了测量的技术路线。测量系统综合应用LabVIEW和它的企业链接、信号处理等工具包，将被测对象的图像和数据直接融合到企业的信息流之中。     

旋锻机锻模头的运动分析

通过分析旋锻机锻头的运动发现传统锻头的不足,利用凸轮轮廓线设计等知识将原锻头结构加以改进后,再运用高等数学的积微分原理将改进后锻头的运动轨迹画出并进行分析,从而得出改进后的锻头结构,能够使对物料的瞬时打击力增大,最终实现提高加工工件时的工作效率和加工精度的目的.     

变转速输入定量泵-恒转速输出变量马达系统恒转速控制方法研究

以变转速输入定量泵-恒转速输出变量马达容积调速系统为研究对象,提出变转速输入定量泵-恒转速输出变量马达容积调速系统的控制方法。建立恒流状态下系统恒转速控制的数学模型,分析系统的相乘非线性特征与变量马达斜盘摆角基准值的计算方法,采用稳态控制量叠加基于小信号线性化补偿控制量的控制方法。通过定量泵-变量马达系统的开环辨识,得到系统参数。对系统进行仿真与试验研究,得到在恒流状态下变量马达斜盘阀控缸的响应速度、马达斜盘摆角和定量泵转速对系统控制特性的影响规律,验证变转速输入定量泵-恒转速输出变量马达容积调速系统的控制方法的有效性。为拓展定量泵-变量马达容积调速系统应用领域奠定了理论基础。     

基于有限状态机的专用盖章机设计与实现

为满足银行对各种票据实现大量且快速盖章的需要,设计并实现了一种银行专用自动盖章机,介绍其机械结构及工作流程,利用有限状态机的思想进行软件开发,实现了一种低成本、高性能的自动盖章机.     

Support vector machine in machine condition monitoring and fault diagnosis

Recently, the issue of machine condition monitoring and fault diagnosis as a part of maintenance system became global due to the potential advantages to be gained from reduced maintenance costs, improved productivity and increased machine availability. This paper presents a survey of machine condition monitoring and fault diagnosis using support vector machine (SVM). It attempts to summarize and review the recent research and developments of SVM in machine condition monitoring and diagnosis. Numerous methods have been developed based on intelligent systems such as artificial neural network, fuzzy expert system, condition-based reasoning, random forest, etc. However, the use of SVM for machine condition monitoring and fault diagnosis is still rare. SVM has excellent performance in generalization so it can produce high accuracy in classification for machine condition monitoring and diagnosis. Until 2006, the use of SVM in machine condition monitoring and fault diagnosis is tending to develop towards expertise orientation and problem-oriented domain. Finally, the ability to continually change and obtain a novel idea for machine condition monitoring and fault diagnosis using SVM will be future works.     

全速前进

可转位硬质合金刀片(ICI)刀具在齿轮制造过程中起着关键的作用。硬质合金刀片刀具具有切削速度快、加工周期短、增强型涂层、采用定制配置、规格和加工能力多样化的特点,被广泛用于精加工和预磨削应用场合。它们继续扩大其独特的性能,并广泛用于刀具市场。拓展经营业务在销售模数5～25的常规系列可转位刀具的同时,很多刀具制造商正在向更大和更小规格的刀具业务进行拓展。当今制造业必须增加刀具生产系列,在某种程度上来说,是由变化多端的市场细分引起的。例如:能源、采矿和重工业领域总是不断地发生着变化。     

钻孔夹具设计

笔者设计的夹具用于钻床上加工斜孔及倾斜台阶面,是一种摆动式钻床专用夹具。通过分析夹具的结构特点、工作原理,计算定位误差、夹紧力、导向误差,说明该夹具设计新颖、结构合理、效率高,同时,还解决了斜孔和斜面加工精度和位置难保证的难题。     

多单元联合机

本论文主要采用智能控制算法对多单元联合机进行控制,利用触摸屏人机界面实现人机交互。智能控制算法可实现多单元跟随与解耦控制,达到各单元同步,采用变增益控制和变积分常数控制,参数可在线调节,使系统在稳、快、准且无稳态误差的条件下运行。     

The intelligent machine

The concept of using condition monitoring (CM) to monitor automated small batch production equipment is now rapidly gaining ground in manufacturing industry due, in the main, to the wide availability of powerful and highly reliable electronic sensing systems, together with advances in computer technology and its associated software. Real time actual condition knowledge or RTACK data, obtained and analysed automatically during the production process, permits the application of many concepts which underpin the methodologies of both condition monitoring and artificial intelligence (AI). These, when used together, have the potential to allow a machine to exhibit intelligence, in the sense that it can be made aware of its environment/health and allowed to adaptively control one to the benefit of the other. The author outlines developments within condition monitoring applied to machining systems, exploring the development of automated, intelligent and unstaffed machining systems     

全自动X光检验机

近日,德国VRM公司推出了两台用于越野轮胎与工程轮胎的全自动：X光检验机：其中,一台小型X光检验机适用于检验直径最大为3500m,宽度为1200mm的轮胎;其次,是一台世界最大的X光检验机,适用于检验直径为4200mm,宽度为1650m,重量约为5t的轮胎。     

Space machine science

The problems of the formation of space machine science, one of the most important branches of the science of machines, and its main application are presented by taking into account the key significance of space exploration both in providing natural conditions for life on Earth and in studying the Universe.     

如何选择数控车床

从实际工作中,总结了选择数控车床应注意的几个问题。