车轮在动态弯曲载荷作用下的应力分析

应用Abaqus软件对某钢制车轮在动态弯曲载荷作用下的应力分布进行了仿真计算,并研究了不同加载方式对车轮应力计算结果的影响。将不同加载方式下所得车轮应力危险点应力变化情况与试验结果进行对比。结果表明,动态加载方式所得应力结果与测试结果较为接近,说明在对弯曲载荷作用下钢制车轮应力进行仿真时宜采用动态加载方法。     

条码生产制造系统(MES)在铝合金车轮生产中的应用(1)

条码技术为生产制造执行系统(MES)提供了最佳数据采集手段。生产现场作业员使用条码阅读器或带有条码扫描功能的手持数据终端,进行现场数据采集,替代人工完成大量工作,使之能准确、及时地采集到过程信息,帮助企业极大地提高生产作业效率和管理水平。     

摩托车轮毂端面跳动的工艺控制

对影响轮毂端面跳动的各类因素进行了分析和试验,虽然人、机、料、法、环各方面对产品跳动质量或多或少存在影响,但在实际生产过程中,如何减少毛坯变形及对现场工艺方法进行规范,是影响质量的主要因素。结合企业实际设备、工艺情况,提出了更加完善的工艺方案,并辅以对现场工艺执行情况进行监控,以及质量控制方案的落实,不断提升产品实物质量,确保加工的产品满足客户要求。     

转向系统固有频率设计研究

转向系统固有频率和整车怠速激励频率吻合而产生的共振是造成整车舒适性下降的重要原因。合适地设计转向系统的固有频率,是解决此类问题的有效手段。     

沥青混合料车辙试验时间研究

多数典型车辙试验的时间高达2h以上,通过车辙试验分析发现,延长试验时间不能带来试验结果平行性的改善,但有助于不同沥青混合料的区分。基于不同荷载与温度条件下的车辙试验发现,材料失稳的关键因素是温度与应力,而不是试验时间。分析指出:低温低压条件下,材料趋于硬化;同时提高试验温度与应力有助于"失稳"出现。     

基于ADAMS的轮式装载机工作装置动态载荷分析

以反转六连杆轮式装载机ZL50G为样机,运用ADAMS软件建立样机的三维实体模型,对轮式装载机的工作装置进行动态载荷分析,为轮式装载机工作装置的研究提供一种可靠的方法.分析结果为轮式装载机工作装置的设计与优化提供了理论依据.     

全驱车型车速检测误差分析

基于对全轮驱动车辆传动系和检测线实际条件的分析,分析了车速误差的原因,制定了可实施的全轮驱动车辆车速检测方案,应用于检测实践中。     

Kinematics of a smart variable caster mechanism for a vehicle steerable wheel

The lateral force of a tyre is a function of the sideslip and camber angles. The camber angle can provide a significant effect on the stability of a vehicle by increasing or adjusting the required lateral force to keep the vehicle on the road. To control the camber angle and hence, the lateral force of each tyre, we can use the caster angle of the wheel. We introduce a possible variable and controllable caster angle ? in order to adjust the camber angle when the sideslip angle cannot be changed. As long as the left and right wheels are steering together according to a kinematic condition, such as Ackerman, the sideslip angle of the inner wheel cannot be increased independently to alter the reduced lateral force because of weight transfer and reduction of the normal load F _z . A variable caster mechanism can adjust the caster angle of the wheels to achieve their top capacity and maximise the lateral force, when needed. Such a system would potentially increase the safety, stability, and maneuverability of the vehicles. Using the screw theory, this paper will examine the kinematics of a variable caster and present the required mathematical equation to calculate the camber angle as a function of suspension mechanism parameters and other relevant variables. Having a steered wheel about a tilted steering axis will change the position and orientation of the wheel with respect to the body of the car. This paper provides the required kinematics of such a suspension and extracts the equations in special practical situations. The analysis is for an ideal situation in which we substitute the tyre with its equivalent disc at the tyre plane.     

Modelling,validation and analysis of a three-dimensional railway vehicle–track system model with linear and nonlinear track properties in the presence of wheel flats

This paper presents dynamic contact loads at wheel–rail contact point in a three-dimensional railway vehicle–track model as well as dynamic response at vehicle–track component levels in the presence of wheel flats. The 17-degrees of freedom lumped mass vehicle is modelled as a full car body, two bogies and four wheelsets, whereas the railway track is modelled as two parallel Timoshenko beams periodically supported by lumped masses representing the sleepers. The rail beam is also supported by nonlinear spring and damper elements representing the railpad and ballast. In order to ensure the interactions between the railpads, a shear parameter beneath the rail beams has also been considered into the model. The wheel–rail contact is modelled using nonlinear Hertzian contact theory. In order to solve the coupled partial and ordinary differential equations of the vehicle–track system, modal analysis method is employed. Idealised Haversine wheel flats with the rounded corner are included in the wheel–rail contact model. The developed model is validated with the existing measured and analytical data available in the literature. The nonlinear model is then employed to investigate the wheel–rail impact forces that arise in the wheel–rail interface due to the presence of wheel flats. The validated model is further employed to investigate the dynamic responses of vehicle and track components in terms of displacement, velocity, and acceleration in the presence of single wheel flat.     

摩托车发动机的噪声源识别

在对某款摩托车发动机噪声源识别试验中,通过声强测量发现,曲轴箱体的表面辐射噪声是主要噪声源,但却不能确定该噪声源的成因。在综合应用了共振频率分析、分别运行法和频谱分析法等噪声源识别方法后,最终发现该噪声源来自发动机的正时链轮和链条的冲击噪声,并发现其位置与声强等高线指示的声源位置并不一致。