电梯溜车现象的分析和对策

电梯溜车是电梯日常使用中经常遇到的一种电梯故障,溜车的主要原因是制动器制动力不足和存在附加的开闸的力所引起的。制动器是保证电梯安全运行的重要部件,由于制动器的故障,电梯就不能正常安全运行。本文通过电梯溜车事故的分析,找到电梯制动器失效的原因,在此基础上提出解决这种现象的办法,以期对解决电梯出现的类似问题会有所帮助。     

浅析电梯制动器的检验要求及故障预防

制动器是曳引式电梯中极其重要的安全装置,制动器在曳引式电梯中具有正常运行制动和电气故障时紧急制动的功能。其动作的准确性和可靠性,影响着电梯运行的安全性和乘客的舒适感。据资料统计,我国现有4万台非安全制动器,每2-3年要发生一次电梯事故。制动器的故障能造成电梯溜车、冲顶或暾底事故。因此,在电梯检验过程中,     

电梯制动器状态检测与失效分析

随着我国经济的不断发展,电梯日益深入人民群众的生活中,而电梯制动器是确保其可以安全运行至关重要的安全部件,决定着电梯的安全性能。在电梯所有的相关电气安全保护均是由电梯内的制动装置来制停电梯,若电梯制动装置失效,则会造成电梯溜车突发事件,电梯将会失控。将针对电梯制动器状态的检测与失效作简要分析。     

试论电梯制动失效原因分析及检验对策

制动器作为曳引式电梯的安全装置,其可靠性直接关系着电梯的安全运行。根据有关数据统计,电梯发生溜车、冲顶事故,跟安全制动器的质量及运行情况有直接关系。通过对电梯制动失效原因进行分析,提出相应的检验对策,为电梯安全运行提供帮助。     

电梯制动器的结构型式及检验检测探究

电梯的安全运行离不开制动器,无论是电梯正常情况下的制停还是故障情况下的紧急制停,均需要制动器的可靠制动,否则将会导致溜车或冲顶事故的发生。现对电梯制动器的结构型式及存在的问题进行了分析,为保证电梯能够按制动要求安全可靠地制动,还对制动器的检验检测方法进行了深入探讨。     

电梯制动器的结构型式及检验检测探究

制动器是维护与巩固电梯安全运转过程的重要装置之一,合理地供能,规避电梯突发溜车事故,进而确保电梯能依照标准制动安稳的停靠在事前设定的位置。本文在阐述制动器的结构型式的基础上,列举了制动器运行阶段的常见问题,为使制动器有效性得到更大保障,利用电气、机械检验检测分析该类保护装置,以供同行参考借鉴。     

电梯制动器的常见故障及解决措施

随着现代化城市建设步伐的不断加快，高层建筑作为了城市的象征，电梯则是高层建筑中不可或缺的必备设施，其安全是非常重要的。大量事故案例表明，电梯人身伤亡事故发生的主要原因之一就是制动器发生故障或者自身存在设计缺陷，从而导致电梯出现冲顶、蹾底、溜车，甚至发生剪切等现象，因此电梯制动器作为电梯结构中至关重要的部件，了解其结构特点以及故障原理，并提出改进措施是非常必要的。     

电梯制动器常见失效形式与检验关键点分析

制动器是电梯中最重要的组成部分，其与电梯的稳定性之间有紧密的关系，如果电梯制动器运行过程中发现失效问题，那么，必然会造成电梯无法安全、稳定运行，甚至会对乘客的生命财产安全带来影响与威胁，所以还需要专业检验部门，对于电梯制动器失效问题加强关注与重视。因此，本文主要对电梯制动器常见失效形式进行分析，最后提出了检验关键点，希望能够在提升电梯运行安全性、保护人们生命安全等多方面起到参考作用。     

超面积病床电梯溜车理论分析及预防

超面积病床电梯存在溜车隐患。通过对一台超面积病床电梯曳引力进行计算,分析了电梯溜车的原因,在此基础上提出了预防超面积电梯发生溜车的措施。     

电梯制动器电气控制及检验

随着现代高层建筑的不断增加,电梯成为建筑运输中必不可少的一项工具,电梯制动器是电梯设计制造中极为重要的一个组成部分,相关设计规范也对这一组成有着极为严格和明确的要求,要保证电梯运输的安全,在确保电梯制动器安全性的同时,电气控制是其中极为关键的一个因素。本文通过分析电梯制动器运行中存在的相关故障问题,进一步探讨电梯制动器电气控制检验的有效对策,为电梯制动器电气控制的安全稳定运行提供理论和实践支持。     

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.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.