汽车动力转向器双工位耐磨损实验装置的设计与实现

汽车动力转向器可靠性直接影响汽车安全性能,为了检测汽车动力转向器耐磨损性能,采用交流伺服液压技术、智能集成技术与微机测控技术等,运用液压站+伺服系统+机械力控制+数据采集和工控组件+温度控制系统+扭矩控制等来达到转向系统的综合性能测试的要求,设计了一台汽车动力转向器双工位耐磨损实验装置系统。     

重型车辆液压转向系统的性能研究与试验分析

汽车转向器是汽车系统的关键零部件,现今的重卡及7 m以上的客车都配备液压助力的动力转向,这种转向可以帮助驾驶员灵活轻便稳定地操纵汽车,因此,汽车液压动力转向器总成后的综合性能试验也就是汽车性能测试中的重要一环,是保证转向器产品质量的关键步骤,该文分析了GY120BX型液压动力转向器的试验结果,得出其转向力特性的对称性为98.2%,灵敏度特性的对称性为81.8%,这两种曲线的形状相似,都具有非常严重的非线性,这对同类型的液压动力转向器的性能研究具有实际的指导意义。     

循环球式液压助力转向系统建模仿真及试验验证

为研究循环球式液压动力转向器对汽车转向性能的影响,采用多领域统一建模语言Modelica,在仿真软件Dymola环境下建立了转向器的机械子系统模型和液压子系统模型,并将所建模型纳入已有的该车转向系统机械模型,构造了完整的液压助力转向系统模型.在仿真和实车环境下分别进行了原地有助力转向和转向轻便性两个试验,试验结果表明所建的转向器模型正确,能准确反映实车的转向性能,为转向器的优化提供理论依据.     

某汽车转向液压系统故障分析与改进

汽车动力转向系统是保证车辆安全行驶的重要系统,该系统为双回路液压系统,主要由分配阀、转向器、转向油箱、溢流阀、精滤器等组成。针对某型号车辆频繁出现的转向器故障,分析了转向系统的工作原理,并深入剖析了加在转向器上的力矩变化规律,找出了动力转向液压系统中转向器频繁损坏的原因,指出了该系统的不足,并提出了相应的改进措施。     

汽车液压助力转向器性能测试台

汽车液压助力转向器常见于高级轿车和重型汽车上。与常规的机械式转向器相比,由于汽车转向时所需的转向力是由液压系统提供而驾驶员转动方向盘仅仅是控制液压系统的动作,因而操作方向盘轻松自如。液压助力转向器实质上是一种液压伺服力矩放大器,转向器的特性主要取决于液压助力特性。为满足安全性的要求,汽车转向器厂生产的每一台液压助力转向器必须经过全面性能测试后才能装车。性能测试项目包括:输入轴转动总圈数和空载力矩、转向器满负载时输入轴力矩、转向器灵敏度和力特性、转向器的回正能力、转向器内部的内泄漏等,所有测试项目均为连…     

浅谈汽车液压动力转向器台架试验方法

正我国汽车工业的快速发展,对液压动力转向器的性能和可靠性要求越来越高,研究符合汽车实际使用工况,准确真实测试该总成各项技术指标的台架试验方法,是非常重要的。转向行业曾在2000年对QC/T5292000《汽车动力转向器―总成台架试验方法》进行过修订,然而十年来,特别是齿轮齿条液压动力转向器新技术的引进,为更进一步修订适合我国国情的液压动力转向器台架试验方法,创造了条件。以下就修订后的新标准与老标准(即Q/CT529-2000)中变化较大的主要项目进行     

创新树品牌 迈向新纪元——记湖北恒隆企业集团公司

两条腿走路 扎实迈出每一步 湖北恒隆企业集团公司生产的产品是汽车转向系统,主要产品有多种型号的汽车齿轮齿条液压动力转向器、循环球液压动力转向器、电动转向器（EPS）、转向油泵、转向管柱、传感器和产品的工艺装备等,产品覆盖国内外多种乘用车、商用车、工程车和发动机。在产品研发方面,集团公司在长春、北京和湖北分别设立了研究院和研究所。企业拥有多项专利。     

超重型特种汽车转向液压系统设计

对转向液压助力系统作了分析研究,设计了超重型特种汽车用转向器分配阀作为主控制阀,由低压控制转向器分配阀、液控换向阀、液控背压阀,提高系统压力、流量,并解决转向器的泄漏问题。     

基于AMESim优先阀的动态特性的仿真

液压优先阀是液压转向系统中的关键元件之一,其性能的好坏直接影响到液压转向系统的可靠性。本文应用AMESim软件对其进行了建模,并通过仿真得出转向器开口面积及阻尼孔面积的变化对液压优先阀动态特性的影响曲线图,通过分析得到在工作负载相同的情况下,增加转向器的流量可以提高转向器的性能,从而实现对液压优先阀的优化。     

BYZ型全液压转向器的常见故障与测试

大型工程机械广泛采用由全液压转向器、液压泵和液压缸组成的液压转向系统，实现机器的动力转向。全液压转向器主要由配流阀、溢流阀和转子泵等组成，溢流阀体上装有安全阀和双向缓冲阀。如果转向器发生故障，在对其进行诊断和修理之后，应进行全面测试。本文分析了全液压转向器的故障原因，并给出了转向器的测试回路和测试方法。 １．常见故障诊断 （１）转向器漏油 上部漏油，转向器阀芯与阀体处密封圈损坏；下部漏油，下盖螺栓松动，或垫圈损坏，或密封圈损坏。 （２）液力转向时，转向盘操纵沉重 液压泵发生故障；人力转向时，单向阀密…     

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.     

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....     

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。     

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.