共查询到20条相似文献,搜索用时 156 毫秒
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任建华 《精密制造与自动化》1996,(3)
一、前言根据磨削技工评价磨床的磨削性能的实践说明,磨削性能是受不同静态刚性、动态刚性和阻尼特性影响的。对于平面磨床,为了提高加工尺寸的精度,应提高静态刚性。但是,磨削烧伤可能会更严重,加工表面的粗糙度更差。为了抑制机床音叉式布局引起的振动而造成工件上的振动刻痕,其动态刚性应提高,但若太高,将会引起不能精确平衡砂轮的问题。为了抑制磨床的音叉式振动,应使磨床具有有效的高阻尼特性。为了满足以上要求,一台理想的平面磨床应能灵活处理以上的问题。为此,我们首先开发了一种可自由改变其静态刚性和阻尼特性的刚性可… 相似文献
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双端面磨床是平面磨床的一个分支产品,具有生产效率高,磨削范围广,连续高效等优点,在汽车制造、轴承加工和航空航天等领域得到广泛的应用。但是受一些因素限制,磨床控制性能落后,加工精度不稳定,制约其质量、可靠性方面的发展。提出了一种对双端面磨床在线检测的补调测量装置,运用气动测量原理对加工工件和砂轮表面进行测量,补偿因砂轮磨损而带来的系统误差,可有效改善运行可靠性差,传递精度低等缺陷,提高了磨床的综合性能。 相似文献
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薄型板件刚性差,平面磨削时很易受热变形和受力变形,要达到较高的平面精度并适应批量生产有一定的难度。它的常规加工方法是在平面磨床上用砂轮磨削;较先进的加工方法是在双端面磨床上磨削;较新型的加工方法是在平面砂带磨床上磨削。某空调压 相似文献
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磨床的动态特性决定了机床磨削的能力、机床磨削的精度,是影响机床性能最为重要的特性。在加工状态下获得机床整机动力学测试结果,是建立机床数字化虚拟样机、评价机床各主要部件动态性能、发现设计缺陷、结构设计优化和机床性能监测的前提。研究基于贝叶斯运行模态分析法(BOMA)对加工状态下的机床整机进行动态性能测试与模态识别,获得整机的模态参数,包括固有频率、模态振型以及阻尼特性等,并对信噪比水平进行评估。 相似文献
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DEVELOPMENT OF A 3-DOF MICRO-POSITIONING WORKPIECE TABLE 总被引:1,自引:1,他引:0
Zhang Dawei Tian YanlingSchool of Mechanical Engineering Tianjin University Tianjin ChinaGaoYongshengSchool of Mechanical Engineering Hong Kong University of Scienceand Technology Hong Kong China 《机械工程学报(英文版)》2004,17(1)
In order to achieve active grinding control, a novel numerical control micropositioning workpiece table with a resolution of 6 nm has been developed. The table is driven by three piezoelectric actuators mounted on the base. An elastic structure with three half-notch flexure hinges is designed to apply preload to the piezoelectric actuators. The position of flexure hinges is also elaborately designed with consideration to reduce the bending deformation of the moving part. Three capacitive sensors are used to form close loop control system. Considering the table as a damped 3-DOF mass-spring system, the models of static and dynamic stiffness and error owing to the action of external forces have been established. In order to make the table have high resolution and positioning accuracy, an error compensation algorithm is implemented by using the established models. The experimental testing has been carried out to verify the performance of the workpiece table and the established models of the micropositionin 相似文献
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ZhangDawei TianYanling GaoYongsheng 《机械工程学报(英文版)》2004,17(1):46-50
In order to achieve active grinding control,a novel numerical control micropositioning workpiece table with a resolution of 6 nm has been developed.The table is driven by three piezoelectric actuators mounted on the base.An elastic structure with three half-notch flexure hinges is designed to apply preload to the piezoelectric actuators.The position of flexure hinges is also elaborately designed with consideration to reduce the bending deformation of the moving part.Three capacitive sensors are used to form close loop control system.Considering the table as a damped 3-DOF mass-spring system,the models of static and dynamic stiffness and error owing to the action of external forces have been established.In order to make the table have high resolution and positioning accuracy,an error compensation algorithm is implemented by using the established models.The experimental testing has been carried out to verify the performance of the workpiece table and the established models of the micropositioning workpieee table. 相似文献
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针对凸轮随动磨削中因工件轴转速差、伺服系统响应偏差、硬件制造误差等重复性误差影响因素造成的零件制造精度下降问题,将在线测量技术和Sinumerik 840D数控系统的插补表与电子齿轮功能应用到机床运动控制系统中,开展了随动磨削工艺的运动轨迹和控制方案分析,提出了由内嵌在系统PCU上的VB程序来处理在线测量获得的360个离散误差补偿数值,自动生成带插补表与电子齿轮功能的专用加工程序,利用同轴运动叠加控制方法,把补偿值叠加到进给轴上,使带误差补偿数据的凸轮加工NC程序不断根据实际加工状态更新,最后在工程样机上进行了磨削试验。试验结果表明,发动机凸轮轴的廓型最大加工误差降到了2.6μm以下,残余误差主要来源为机械振动、非线性摩擦扰动等随机性偏差。该运动控制和误差补偿方法能在实际加工中较好地补偿重复性误差因素对工件精度产生的影响。 相似文献
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Jorge L. García Denisse G. Rivera Alejandro Alvarado Iniesta 《The International Journal of Advanced Manufacturing Technology》2013,66(1-4):537-545
To machine a noncoaxial nonaxisymmetric aspheric lens, a new parallel grinding method that employs a fixture with an adjustable gradient (AGF) is proposed. The AGF is developed for a three-axis computer numerically controlled grinding machine. The grinding method is presented according to the proposed grinding system. To ensure the machining accuracy, the main machining errors and the compensation algorithm are discussed for the grinding method using the AGF. Simulation results show that the AGF rotation errors are crucial factors affecting the profile error of the machined workpiece. Experimental results show that employing the compensation algorithm increases machining accuracy. 相似文献
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Qinghua Song Xing Ai Weixiao Tang 《The International Journal of Advanced Manufacturing Technology》2011,55(9-12):883-889
A method for predicting simultaneous dynamic stability limit of thin-walled workpiece high-speed milling process is described. The proposed approach takes into account the variations of dynamic characteristics of workpiece with the tool position. A dedicated thin-walled workpiece representative of a typical industrial application is designed and modeled by finite element method. The curvilinear equation of modal characteristics changing with tool position is regressed. A specific dynamic stability lobe diagram is then elaborated by scanning the dynamic properties of workpiece along the machined direction throughout the machining process. The results show that, during thin-walled workpiece milling process, material removing plays an important part on the change of dynamic characteristics of system, and the stability limit curves are dynamic curves with time?Cvariable. In practical machining, some suggestion is interpreted in order to avoid the vibrations and increase the chatter free material removal rate and surface finish. Then investigations are compared and verified by high-speed milling experiments with thin-walled workpiece. 相似文献
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凸轮轴磨床数控系统的研制 总被引:3,自引:0,他引:3
介绍了研制的一种适合国情的凸轮轴磨床数控系统。该系统采用摇架式数控成形,工件转动和摇架摆动之间采用强迫耦合技术,并数字调节技术来提高工件的轮廓控制精度。介绍了该系统的技术特点和数字调节器的设计。 相似文献
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数控机床热误差的动态自适应加权最小二乘支持矢量机建模方法 总被引:9,自引:2,他引:9
为消除数控机床热误差对加工精度的影响,提出基于动态自适应加权最小二乘支持矢量机的数控机床热误差建模方法.为构建机床热误差模型,对一台XK713数控铣床进行建模试验,采用智能温度传感器与激光位移传感器分别获取机床温度值与主轴变形量.运用动态自适应算法,优化选择建模过程中的参数;对采样数据进行初始最小二乘支持矢量机建模,根据误差变量确定权重系数,得到基于加权最小二乘支持矢量机的数控铣床热误差模型.试验结果表明,基于动态自适应最小二乘支持矢量机的数控机床热误差建模方法精度高,泛化能力强,优于未加权最小二乘支持矢量机方法与传统最小二乘法.获得的模型可用于数控机床热误差补偿,以提高数控机床的加工精度. 相似文献