一种新型锥环式CVT定速比试验研究

在分析锥环式CVT结构原理基础上,开发了锥环式CVT定速比试验研究试验台。针对锥环式CVT传动副独特结构及润滑条件,设计了CVT速比控制机构和循环牵引油温度自动控制系统,并实现了与台架的一体化控制。在此基础上,建立了锥环式CVT定速比耐久性试验和效率试验方法,进行了锥环式CVT传动副定速比试验及传动效率试验。结果表明,锥环式CVT定速比试验较准确的考核了锥环传动副传动效率,其结构强度通过了验证,各速比下传动效率均在84%以上,为下阶段锥环式CVT进一步优化、改进提供了依据。     

行星环锥齿轮式功率分流的无级变速器的分析与研究

基于传统的牵引式行星环锥式摩擦无级变速器,首先,提出了行星环锥齿轮式功率分流的无级变速器的设计方案;然后,对其整体变速比作出了两种方法的推导,并对功率流方向和功率流的分配关系作出了准确的判断;最后,对变速系统的整体传动效率进行了详细的分析计算,并用实例进行计算,与原行星环锥无级变速器传动效率进行了比较分析,并根据功率分流的比例图得出了总输入功率数值大小的范围。结果表明,经改进后的行星环锥齿轮式功率分流无级变速器的传动效率不仅比原来行星环锥无级变速器提高很多,而且总的输入功率可达到原来的行星环锥式无级变速器几倍之多,实现了大功率传动。     

新型活齿无级变速器转矩传递能力的试验研究

为研究啮合传动式新型活齿无级变速器(Innovative Movable-teeth CVT,i MCVT)的转矩传递能力,分析了其结构和工作原理,并与摩擦传动式金属带式无级变速器的转矩传递能力进行了对比分析;搭建了传动效率试验台,进行了三种工况下i MCVT传动效率与传递转矩关系的试验研究。结果表明,在三种试验工况下,新型活齿无级变速器稳定运行时,传递的转矩可达到220 N·m左右。当传递的转矩在180~220 N·m时,传动稳定,传动效率较高。与金属带式无级变速器相比,转矩传递能力更强,并且在传递大转矩时仍能保持92%的传动效率。     

高效率功率分流RX行星锥环无级变速器的研究

根据RX型行星锥环无级变速器的传动原理和结构特点，针对其现有的缺陷，提出了一种高效率、大功率、没有封闭循环功率的功率分流无级变速器，并对其功率计算进行了理论分析，通过具体实例计算并比较了其和RX型锥环无级变速器的效率。     

金属带无级变速器传动性能的试验研究

采用试验研究的方法,对金属带无级变速器的传动性能以及影响因素进行了研究。设计制造了专用的CVT传动试验装置和电液控制变速系统,搭建了传动性能测试试验台,并进行了性能试验。试验结果表明,传动比、输入转矩和带轮油缸压力对传动性能有较大影响,输入转速对CVT传动效率也有较大影响。     

高效率功率分流式RX行星环锥无级变速器研究

根据RX行星环锥无级变速器的传动原理和结构特点,针对其现有缺陷,提出了一种高效率、大功率、没有封闭循环功率的功率分流无级变速器,并对其功率进行了理论分析,按具体实例计算其效率.     

金属带式无级变速器带轮变形摩擦损失分析

金属带式无级变速器(CVT)的带轮变形会导致金属带沿着带轮锥面发生径向偏移,从而使得系统产生摩擦损失,严重影响变速机构的传动效率.以某国产CVT为研究对象,建立了带轮变形摩擦损失模型并利用ANSYS软件对金属带式无级变速器传动部分进行有限元仿真分析.分析结果表明:速比是影响带轮变形的主要因素,带轮锥面最大变形量随着工作...     

新型摩擦式无级变速器的开发及其应力应变的改善性分析

为了解决目前实际生产中常用的单滚轮平盘摩擦式无级变速器(CVT)中出现的一些重要部件关键部位的受力不均匀问题,在单滚轮平盘摩擦式无级变速器结构的基础上,利用两个平盘和二次摩擦传动,开发了一种新型多滚轮摩擦式无级变速器。首先,叙述了该无级变速器的传动原理;然后,给出了4种无级变速器可以采用的具体传动结构形式;最后,利用有限元分析软件ANSYS计算出了在某一例数据下两种变速器相应的关键部位的应力和应变云图,并以其数据为依据进行了对比分析。研究结果表明,采用该新型变速器其相应部位的应力及应变情况都有了较大的改善,同时显示了该新型变速器在受力方面的优势。     

车辆金属带无级变速传动效率优化设计

论述了无级变速传动系统的基本结构,并将车载无级变速器（CVT）动力传动系统与手动变速传动效率比较。详细描述了CVT系统中各单元功率损耗的机理,介绍了通过优化变速器结构与控制策略,抛弃油泵,优化设计DNR及其它相关耗能单元等措施,以降低CVT动力传动系统中功率损耗,并将优化设计后的CVT（机械电子CVT即EM-CVT）效率与电液式CVT效率进行比较,结果验证EM—CVT在传动效率方面取得了良好的效果。优化的CVT系统对进一步降低金属带无级变速传动轿车的燃油消耗和改善尾气排放具有重要意义。     

基于传动集成控制的锥环无级变速方法的研究

本文研究了一种新型汽车无级变速机构,其由两个圆锥体和一个金属锥环组成,锥环式无级变速器利用锥环本身的机械特性,实现变速器速比的转换。在Matlab/Simulink环境下建立了整车动力传动系一体化控制仿真模型,根据PID控制器的控制原理及特点对传统的PID控制器进行了改进,并对几种典型行驶工况进行了仿真分析,仿真结果表明,设计的调速控制策略能适应车辆各种行驶工况的要求,实际速比能很好地跟随目标速比。     

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.