三弧段等距型面的几何要素及其加工

三弧段等距型面联接属于无键联接之一,按其结构可分为柱面联接和锥面联接(见图1)。柱面联接只能传递扭矩,锥面联接除传递扭矩外,还可承受轴向载荷。三弧段等距型面联接具有拆装方便,疲劳强度高,能自动定心和制造容易等优点。本文主要论述三弧段等距曲线的形成、几何要素和方程,指出了三弧段等距型面联接轴与孔的加工方法。     

基于ANSYS等距型面轴孔配合特性的研究

等距型面联接作为代替各种键联接的一种典型联接结构,也已广泛的应用于各种机械传动系统中。利用ANSYS有限元分析,对等距型面轴孔配合特性进行仿真模拟。结果表明:用同一有限元程序,在等距型面轴的平均半径与平键轴的半径相同、材料相同、所受的载荷相等的情况下,等距型面联接比平键联接在强度方面存在着优越性。     

等距型面联接轴的实用强度计算

等距型面无键联接以其传递据矩大、拆装方便、对中性好等优点,日益得到国内外科技工作者的广泛关注。在等距型面联接的设计或选用过程中,轴的强度验算是十分必要的。本文从等距型面联接的工作原理入手,提出了等距型面联接中轴的实用强度计算方法。     

等距型面轴的磨削加工

一、前言等距型面是异形截面的一种，由等距型面轴、孔配合构成的联接称等距型面联接。该联接具有自动定心，装拆方便，制造简单，可传递大扭矩等优点。在直径相同的条件下，等距型面联接可比渐开线花键联接多传递35％的扭矩，且较其它联接具有较大的抗剪能力。目前，其应用范围正在不断扩大。二、等距型面的边界方程等距型面的边界方程是一条非圆的光滑简单闭曲线，在这条曲线上，任意两平行切线之间的距离相等（设常数D，一般称等距值），故称等距（也称等宽或等厚）曲线（见图1），其方程推导如下。如图2所示，建立直角坐标系，则直线G…     

基于Master CAM及MATLAB6.5环境下靴形曲面的CAD/CAM优化设计

详细阐述了在Master CAM及MATLAB6．5环境下靴形曲面的CAD／CAM优化设计过程。利用MasterCAM软件的曲线融合功能按曲面表面受力从小到大的规律设计曲面的导线，通过曲面造型功能完成靴形曲面的设计。充分应用Master CAM软件的CAM功能实现加工曲面的刀路优化设计。并利用MATLAB6．5软件建立同类型曲线的数学模型，完成了同类型曲面的优化设计。     

任意基三角形的等距曲线设计

对型面联接中以任意基三角形的等距曲线进行设计。讨论了设计原理、作图方法、及其证明和特性应用，从而进一步完善了等距曲线型面联接的设计途径和方法。     

等距曲线型面联接轴设计

等距曲线型面联接轴设计赵（包头市职工大学）１引言在机械传动中利用非圆形剖面的柱体或锥体，与轮毂上相应的孔配合构成的联接，称为型面联接或成形联接（如图１）。采用型面联接传递转矩时，具有以下优点：（１）能保证良好的对中性；（２）联接面上没有键槽和尖角，无...     

用数控铣床加工等距型面孔

用等距型面轴与孔配合构成的联接称为等距型面联接,它具有自动定心、装拆容易、能实现间隙配合装配以及过盈配合工作等优点。利用等距型面联接代替花键联接,可以提高轴的疲劳强度,明显降低机械传动系统的振动和噪声,因等距型面的型面曲线上任意两平行切线间的距离都相等,其测量和加工都比较方便。特别是近几年,随着数控机床的推广应用,等距型面的许多加工问题也逐步得到了解决。     

函数曲线在Master CAM中的快速设计

在加工含有函数曲线的二维异型零件时,往往选择宏程序或者通过其他软件来解决,但生成加工程序最快最好的却是Master CAM,本文就如何在Master CAM中使用Fplot功能快速设计已知的函数曲线问题做了详细的研究及应用。     

球磨机中等距型面联接强度的分析与研究

采用有限元分析方法,分别对等距型面联接和平键联接的两种联接强度进行了计算与分析,同时依据弹性接触理论,又对两种联接中的接触应力进行了研究与比较.研究结果显示了等距型面联接强度的优越性,从而为球磨机中传动部件联接的改进提供了重要的理论依据.     

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...     

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.     

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.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

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....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.