高精度蜗杆和其他螺旋齿形采用CNC蜗杆和螺纹磨床的经济性生产

1.引言很久以来,成形磨削法一直用于蜗杆和螺纹状工件的磨齿。为了使这种高效工艺能提供所希望的经济性,现代化蜗杆和螺纹磨床必须满足有关砂轮的准确成形,生产时间短、高效金属磨削、调整更换时间和非生产肘间少等方面的要求。此外,在某些应用领域内(例如机床、升降机驱动系统等中的定位传动装置),在齿形、导程和齿距中取得高精度是必要的。     

ZC1蜗杆磨削用CNC砂轮修整器设计

ZC1型蜗杆因具有良好的传动性能和综合效果而备受关注,磨削加工是提高传动性能的关键,磨削用砂轮的修型方法直接影响其加工精度.根据ZC1蜗杆磨削的数学模型,提出了一种专用的砂轮修整器结构模型,设计了一种CNC砂轮修整器的系统结构,为提高ZC1蜗杆的磨削加工精度和效率提供一种新途径.     

ZC1蜗杆精密磨削加工

基于成形砂轮对工件进行磨削加工的原理,应用空间啮合理论对ZC1蜗杆磨削过程进行理论推导,得出了唔合线方程和砂轮轴向截形的数学模型,利用MATLAB软件计算出砂轮的轴截形并利用此截形数据在配有CNC砂轮修整器的数控螺纹磨床上对砂轮进行修型,用修型好的砂轮磨削工件从而实现对蜗杆的精密加工.     

精密、超精密圆柱渐开线齿轮的加工方法

超精密齿轮的制造质量反映出了一个国家制造业的发展水平。分析比较了锥形砂轮磨齿、蝶形砂轮磨齿、大平面砂轮磨齿、蜗杆砂轮磨齿和成形砂轮磨齿的工作原理及当前国内外精密、超精密圆柱渐开线齿轮的加工现状,探讨了ISO1328-1997标准中2级以上精度超精密齿轮的加工。并论证了国产大平面砂轮磨齿机Y7125由于具有结构简单、传动链刚度高、具有较高的磨齿精度以及较大的改装空间等优点,通过一系列的研究工作,有可能把它改装精化成磨削超精密圆柱渐开线齿轮的加工母机,实现2到1级精度超精密齿轮的加工。     

基于VERICUT的ZC1蜗杆磨削仿真技术

基于磨削啮合原理建立ZC1蜗杆磨削过程的数学模型。根据空间坐标转换与啮合原理推导出砂轮轴向截形方程,借助MATLAB软件计算砂轮截形,生成其离散点数据,并在SolidWorks平台下建立砂轮与磨削机床几何模型。在VERICUT平台中编制数控程序进行仿真磨削加工,提取蜗杆截形,并测量虚拟误差,分析了磨削过程中当交错角变化时蜗杆截形的误差变化趋势,为ZC1蜗杆的精密磨削加工提供新思路。     

基于虚拟中心距原理的鼓形蜗杆砂轮成形修整方法

为了在普通蜗杆砂轮磨齿机上磨削面齿轮，提出在普通蜗杆砂轮磨齿机上修整面齿轮磨削用鼓形蜗杆砂轮的方法。通过母线螺旋扫掠的方式将面齿轮插齿刀向蜗杆砂轮演变，给出面齿轮磨削用鼓形蜗杆砂轮的演变计算方法，建立鼓形蜗杆砂轮的型面方程；分析鼓形蜗杆砂轮型面特征和磨齿机修整机构的运动特性，提出基于虚拟中心距加工原理的鼓形蜗杆砂轮成形修整方法，将砂轮的偏心摆动作为修整冲程运动，通过四轴联动方式修整鼓形蜗杆砂轮螺旋面；最后采用VERICUT对所提修整方法进行仿真验证，表明采用该方法在普通蜗杆砂轮磨齿机上能够有效修整鼓形蜗杆砂轮。     

蜗杆砂轮磨齿工艺

提高磨齿工艺的生产能力是齿轮加工技术的一项重大课题。西德Aachen工业大学教授、工学博士W.Konig发表了一项旨在提高磨齿生产能力和磨削质量的蜗杆砂轮连续展成磨齿工艺的研究报告,通过试验比较得出的数据,颇有参考价值。一、概述蜗杆砂轮连续展成磨齿法采用带有精确齿条齿形的蜗杆砂轮(图1)和被磨齿轮在一个同步电机带动下,通过砂轮对齿轮的滚磨产生渐开线齿形和工件在拖板带动下作上下移动来完成的。加工时需要调整的数据有:轴     

大型数控成形磨齿齿面误差控制研究综述

相比于蜗杆砂轮磨齿,成形磨齿适用于大直径大模数齿轮的高效磨削,但也存在磨削精度控制难、精密修形难、在机精密检测难等问题.综述成形磨齿齿面误差控制方面的国内外研究和发展,从砂轮修整系统误差、齿轮磨削系统误差以及在机检测系统误差3个误差源方面对近些年国内外研究成果和存在的问题展开讨论,提出了需要进一步深入研究的方向和内容:...     

面齿轮蜗杆砂轮的成形修整工艺误差建模及补偿方法

蜗杆砂轮磨削是面齿轮的精加工工艺,蜗杆砂轮修整精度直接影响面齿轮磨削精度。本文分析了修整工艺误差对磨削齿面误差的影响规律,并提出了一种面齿轮蜗杆砂轮的成形修整工艺误差建模及补偿方法。首先,建立面齿轮蜗杆砂轮的数学模型,分析面齿轮蜗杆砂轮的成形修整原理,提出利用圆柱齿轮磨齿机的多轴耦合联动实现面齿轮蜗杆砂轮的成形修整。其次,将修整工艺误差分为轴向位置和径向位置误差,分析轴向位置和径向位置误差对磨削齿面误差的影响规律,提出成形修整工艺误差的补偿方法。最后,进行蜗杆砂轮补偿修整、面齿轮磨削加工及测量实验,实验表明：左齿面齿形误差由补偿前51.9μm到补偿后7.9μm,右齿面齿形误差由补偿前35.3μm到补偿后17.6μm,验证了误差补偿方法的有效性。     

磨齿成形砂轮的修整

解决砂轮的成形问题,直至现在,仍决定于成形磨削的继续发展。成形磨削的砂轮修整,从初期的两种方法逐渐补充并得到完善,使得成形磨削在生产中发挥了作用。一、前言当展成磨削在磨齿加工中处于主要手段的情况下,齿轮磨削加工在机械制造业中是一种价格昂贵的工种。因要降低它们的成本,目前所采用的这种齿轮磨削方法将被其它精加工方法所代替。在磨齿时,应该根据生产的需要,选择渐开线成形磨削或展成磨削两种不同的方法,而展成磨削又分     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.