驼峰车辆减速器制动性能影响因素分析

驼峰作业过程中,溜放车辆经减速器制动后容易出现超速、夹停、轻车挤出等制动问题。通过理论分析和实验方法,分析制动高度、制动宽度、轮辋外径变化、摩擦系数等因素对减速器制动性能的影响情况。结果表明:提高摩擦系数和制动高度、增大杠杆比、减少制动宽度等,能有效降低减速器超速的发生概率;提高制动高度、减少附加制动力系数、提高制动轨强度、降低摩擦系数等,能有效降低轻车挤出的发生概率;提高传动系统动力、减少零部件摩擦阻力、增大曲拐偏心等,能有效避免夹停问题的发生。由此提出解决减速器制动问题的措施和建议,为减速器设计、安装施工、维修维护等,提供理论支持和设计依据。

某轻卡商用车进气系统设计

进气系统是发动机的重要部件之一,其主要作用是向发动机提供充足洁净的空气,保证发动机缸内燃料燃烧所需的空气,随应用环境的多样化,进气系统被赋予了更多的用途,例如在雨天行使环境中,要求进气系统在提供空气的同时,需避免雨水随空气进入发动机燃烧室,造成发动机损坏,这就需要进气系统在防雨结构上进行优化升级,本文主要介绍了某轻卡商用车进气系统的雨水分离功能及通过进气系统布置方案的选择,零部件的结构设计实现雨水分离效率目标的过程及方法。

新能源轻卡物流车转向系统发展趋势

新能源汽车的发展是落实国家节能减排、发展低碳经济政策的重要战略。随着智能化的大力发展,新能源轻卡物流车转向系统已由传统电动液压助力转向(EHPS)系统向纯电动助力转向(EPS)系统转变,未来将实现纯线控转向(SBW)系统技术。结合EHPS、EPS的结构、原理、控制逻辑及优劣势,浅谈新能源轻卡物流车转向系统发展趋势。

碳减排与超限禁入外部效应下轻量化商用车供应链演化博弈分析

轻量化商用车是“双碳”目标下碳减排、超限禁入政策法规实施后,公路交通长距离货运绿色化最具发展前景的可行技术路径。为促其供应链稳态发展,在分析不同主体演化博弈决策行为的基础上,构建以制造商、经销商、消费者为主体的三方演化博弈模型,并给出演化稳定状态主体行为策略;进一步,通过建立系统动力学模型,仿真分析不同情况下利益主体的策略选择,以及外部变量取值变化对系统演化稳定策略的影响。结果表明:政策法规外部效应下消费者需求与市场结构转变有诱致性和强制性两种演化形式,且与政策法规的缓释周期相关。当缓释周期较长时,制造商为适应市场结构转变,先于消费者积极参与,对产品部类结构优化,诱致消费者需求调整,并经过较长周期使轻量化商用车供应链演化至稳定状态;当缓释周期较短或不存在时,消费者收益路径依赖阻断,出于从业和运营的可持续性考虑,消费者迫于政策法规外部效应的强制性,进行需求调整,参与轻量化商用车供应链,并通过需求侧“拉”和政策法规外部效应“推”促使制造商与经销商参与其中,最终以较短周期实现上述供应链演化至稳定状态。最后,政策法规缓释周期的动态调整应与技术迭代保持同步性,从而更好地发挥政策法规外部效应,使供需两侧形成双向反馈机制,有利于较短周期内轻量化商用车供应链演化至稳定状态。

轿车/轻载车子午线轮胎主要外观缺陷的原因分析及解决措施

结合轿车 /轻载车子午线轮胎生产实际 ,对影响子午线轮胎外观质量的 4种主要缺陷 ,即定型不当造成的胎圈宽窄不一、欠硫、胎里疏露线 /胎里窝气及缺胶、裂口和重皮的表现形式及产生原因进行了深入细致的分析 ,并提出了相应的工艺、设备、操作等方面的调整改进措施 ,这些措施可有效地避免或解决子午线轮胎的以上

窑车结构设计的改进与窑具材料的应用

本文介绍了近几年陶瓷工业用赛车结构的改进和高性能窑具材料的应用，及其对提高陶瓷工业的生产效率、制品质量与降低烧成能耗、生产成本的影响。

一种轻质电动林业单轨车的设计

为构建丘陵地区林果快速集运系统,降低运输成本和鲜果褐变几率,实现节能减排、顺应车辆轻量化发展趋势,设计了一种基于摩擦驱动的轻质电动林业单轨车。该单轨车兼容轮毂电机直接驱动和调隙转向装置,省去了变速箱、离合器等装置,配装72V20Ah的锂电池供电,使得单轨车车体结构简单轻巧,轨道不需设置齿条,使得轨道部署方便且节约成本,在车体转弯时车轮受到轨道的压力能自由调节间隙。根据所设计的单轨车结构,建立车体转弯的接触模型,分析车体动力学模型和ADAMS仿真模型以验证该设计方案。结合设计参数及仿真试验结果研制样机,所得样机中单轨车车体质量减少50.54%、轨道质量减少22.46%。试验得出样机能通过20°坡道和最小转弯半径6 m的弯道,并通过电机自带的适配器将电机限速至30%和线性调速部件组合控制行驶速度在0.5~1.5 m/s范围内,提高了单轨车的运行效率。本研究所设计的轻质电动林业单轨车为实现丘陵山区的快速运输提供了技术装备支持,为后续自巡航无人遥感电动单轨车研制奠定了基础。

Recent development in aluminium for automotive applications

Aspects of material selection and innovative concepts of car construction using aluminium as best suited light-weight materials were presented, and recent development in established and advanced use of aluminium in passenger cars was discussed that help to meet economic and environmental requirements. 5xxx and 6xxx aluminium alloys were presented that have been improved for the increasing demands regarding higher strength and better formability, resulting in a mass reduction and improved crashworthiness. Furthermore, advances concerning multi-material light weight design were presented by examples for aluminium solutions in advanced “Multi-material” Super-Light-Car （SLC） concepts, which reaches significant mass reductions.

On the automobile lightweight

The significance,description parameters,evaluation method,implement way and design for lightweight of automobile are comprehensively reviewed.The relationship among the performances of auto parts & components,the properties of materials and application of advanced technologies is also elaborated.According to recently related progress of lightweight and authors' research and developing work,lightweight of automobile is comprehensively and systematically overviewed.

Effects of fundamental factors on coupled vibration of wind-rail vehicle-bridge system for long-span cable-stayed bridge

In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundamental factors,such as mean wind,fluctuating wind,buffeting,rail irregularities,light rail vehicle vibration and bridge stiffness.A long cable-stayed bridge which carries light rail traffic is regarded as a numerical example.Firstly,a finite element model is built for the long cable-stayed bridge.The deck can generally be idealized as three-dimensional spine beam while cables are modeled as truss elements.Vehicles are modeled as mass-spring-damper systems.Rail irregularities and wind fluctuation are simulated in time domain by spectrum representation method.Then,aerodynamic loads on vehicle and bridge deck are measured by section model wind tunnel tests.Eight vertical and torsional flutter derivatives of bridge deck are identified by weighting ensemble least-square method.Finally,dynamic responses of the WVB system are analyzed in a series of cases.The results show that the accelerations of the vehicle are excited by the fluctuating wind and the track irregularity to a great extent.The transverse forces of wheel axles mainly depend on the track irregularity.The displacements of the bridge are predominantly determined by the mean wind and restricted by its stiffness.And the accelerations of the bridge are enlarged after adding the fluctuating wind.

Prediction of hot tearing susceptibility of direct chill casting of AA6111 alloys via finite element simulations

To predict hot tearing susceptibility(HTS)during solidification and improve the quality of Al alloy castings,constitutive equations for AA6111 alloys were developed using a direct finite element(FE)method.A hot tearing model was established for direct chill(DC)casting of industrial AA6111 alloys via coupling FE model and hot tearing criterion.By applying this model to real manufacture processes,the effects of casting speed,bottom cooling,secondary cooling,and geometric variations on the HTS were revealed.The results show that the HTS of the billet increases as the speed and billet radius increase,while it reduces as the interfacial heat transfer coefficient at the bottom or secondary water-cooling rate increases.This model shows the capabilities of incorporating maximum pore fraction in simulating hot tearing initiation,which will have a significant impact on optimizing casting conditions and chemistry for minimizing HTS and thus controlling the casting quality.

没有运气的李广

运气对一个人来说实在太重要了。汉武帝攻伐匈奴时,起用了四位大将,他们是车骑将军卫青、骑将军公孙敖、轻车将军公孙贺、骁骑将军李广。论对边塞及敌情的熟悉,论指挥才能和武艺胆略,李广应居四将之首。

矿车轻/重车运行状态距离判别分析模型

为了判别出矿用巨型卡车在行驶过程中的轻/重车运行状态,提出了一种轻/重车运行状态距离判别分析模型。通过选取矿车行驶过程中的轮胎气压、轮胎温度、速度、加速度和环境温度5个指标作为判别因子,利用97组样本数据作为训练样本,基于距离判别法基本原理,选用马氏距离为判别距离,建立了该判别分析模型。通过训练样本的回代结果以及假设检验结果证明了该模型的合理性。利用该模型,实现了对待判样本的准确判别,说明该模型可以应用到矿用巨型卡车的轻/重车运行状态的判别。

不同补贴策略下轻量化商用车供应链决策与社会效益分析

构建以制造商为主导的stackelberg博弈模型,分析政府不同补贴策略对轻量化商用车供应链主体的研发制造投入、营销努力投入、购买决策及所带来的社会效益的影响。结果表明:轻量化商用车市场规模大小取决于消费者的偏好程度,而消费者的偏好易受价格影响。无补贴情况下,高价格敏感度导致传统商用车市场规模远大于轻量化商用车市场,且长远来看,不利于轻量化商用车市场的发展;在制造商和经销商补贴策略下,轻量化商用车市场需求量、供应链价值及社会效益有明显升高,其中经销商利润增加最为明显,但其市场需求量并不理想;而消费者购买补贴策略下,轻量化商用车市场上需求量有较大幅度提升,销售价格也较第一种补贴策略显著下降,社会效益最高;研究显示:无论政府采取何种补贴策略,只要补贴力度在合理范围内,对轻量化商用车供应链价值及社会效益均起着正向促进作用。

加减速顶引起轻车脱轨的原因和防范对策探讨

本文通过分析柳州南站加减速项造成轻车脱轨的现象，探讨了导致这一现象发生的主要影响因素，指出了加速顶异常使用的危险性，并提出了避免这类事故的防范对策。

Research on plastic fender development and key technologies

Automotive lightweight and safety performance come into play as key technologies to promote competiveness, and average applied amount of automotive plastics has become a significant sign for automotive industrial development level of a country.Various performances of a vehicle with plastic automotive fenders are analyzed in the paper.The research is emphasized on sinking-resistance and pedestrian protection performance of the plastic fenders by studying plastics characteristics and simulation analysis.It offers references for engineering design in which both automotive lightweight and safety performance are achieved and well balanced.

自动化驼峰间隔制动位短轻车控速程序改进

采用T.JK非重力式减速器作为调速工具的自动化驼峰,在间隔制动位对短轻车进行速度控制时,由于采用"闯口"式控制模式,容易造成低速出口。为此对速度控制方式提出了"适度放入"的改进方法,并在怀化南驼峰控制系统进行了实施,提高了系统对短轻车的控制精度。

高强钢板在商用车轻量化车厢上的应用对策

高强钢板拥有高强度,它是在正火或正火加回火的状态下形成较高综合力学性能的,它主要被应用于大型桥梁、船舶、起重机械以及机车车辆中。特别是在生产大量的机车车辆中,为了实现车体轻量化目标,汽车上越来越多开始使用高强钢板结构件。文章探讨了高强钢板在商用车轻量化车厢的设计应用,并基于不同材料展开撞击对比模拟试验,验证高强钢板的实用性能。

The test device for heat friction coefficient of high strength steel

Using high strength steel and ultra-high strength steel in hot stamping and automobile parts is one of the most important ways of the automobile lightweight,which is the development trend of automobiles currently.In this paper, the development of test device for heat friction coefficient by high strength steel can provide important technical parameters for hot stamping process,making the right selection of equipment types,mold design,technology optimization,and research and development of lubrication medium of press forming.At the same time,the experiments indicate that the instrument has not only accurate test result but also good repeatability.

轻车跳动影响调度集中正常使用的解决方案

长春轻轨一期工程信号系统采用25Hz相敏轨道电路,运营初期出现轻车跳动现象,影响行车安全,并使调度集中系统车次号跟踪功能失效。简要分析轻车跳动产生的原因,重点阐述解决轻车跳动的方案。