CSP连铸机扇形段辊缝在线测量系统的设计与应用

简介了CSP连铸机的工艺流程,分析了按常规方法无法对CSP连铸机扇形段实现辊缝在线测量的原因,创新设计了一种新型连铸机扇形段辊缝在线测量系统,实现了连铸机扇形段的辊缝在线测量,并有效提高了连铸机扇形段辊缝测量的精度和准确度。     

捷达前卫 空调不工作

故障现象：有一辆捷达前卫轿车,开空调时出现空调电磁离合器不吸合故障,但散热风扇低速转。 故障诊断：测量蒸发器处的温控开关,有12V电压,并且开关处于导通状态;测量高压管上的低压压力开关,低压开关导通,并且12V电压到位;拔下控制单元插头,测量发动机控制单元线束插头28脚（空调打开信号输入脚）电压，在开空调时有12V电压，关空调后为OV；测量控制单元76脚（空调继电器控制脚）电压，开空调时电压为12V，关空调时电压也为12V。     

如何克服瓶颈

轻量校正辊能够解决典型的纸机问题，例如次优化的纸幅张力测量、速度限制、开机问题和打滑     

iRoll获得创新奖

iRoll是第一个能够自动在线测量线压分布状况的辊简，被法国技术协会评为最重要的一项技术创新     

车架纵梁辊压轮国产化技术的研究与应用

本文介绍了在组织国外引进的纵梁辊型生产线辊轮国产化过程中,系统地进行辊轮测量、同类功能件参数比对及技术分析采用的措施和方法,并用样件试制及生产实验论证辊轮国产化转化应用的技术过程,不仅是可靠的,也是十分必要的。     

帕萨特车空调压缩机电磁离合器不吸合

故障现象一辆帕萨特B5轿车(采用手动空调),车主反映该车空调压缩机电磁离合器只能在冷机情况下吸合,吸合后将空调(A/C)开关断开,再接通空调压缩机时电磁离合器就不再吸合,使得空调制冷系统不能正常工作。故障诊断通过实车验证,空调开关接通时其上的指示灯正常,用空调歧管压力表组测量空调系统内的制冷剂压     

基于正交试验法的防撞梁耐撞性研究

针对国内某轿车前保险杠的吸能特性,本文采用正交试验法选定横梁外板的材料、厚度、结构为影响因素,利用Hypermesh有限元软件建立该保险杠的正面碰撞有限元模型,并基于Ls-Dyna求解器对保险杠横梁的最大位移及缓冲吸能装置的吸能特性进行了数值仿真。仿真结果表明:采用铝合金材料,厚度为2.5mm的辊压成形结构防撞梁在10km/h的低速正面碰撞工况下,碰撞后的安全距离最大,吸能特性最好。     

桑塔纳俊杰自动变速器换挡杆不锁止

故障现象：自动变速器换挡杆在运行时不踩制动踏板可以在任意挡位间切换。故障诊断：该车配置01N四挡自动变速器，用故障诊断仪V.A.G1552查询自动变速器控制单元无故障码，用万用表测量换挡杆锁止电磁阀的阻值与新的电磁阀一样，再测量其两端电压，当不踩制动踏板时为0V，踩下制动踏板时还为0V。该电磁阀通过变速器控制单元受控于制动灯开关F。当踩下制动踏板时制动开关F闭合，从蓄电池正极来的30号电源经过制动开关F分为两路，一路给制动灯供电，使制动灯亮，另一路给变速器控制单元一个制动踏板踩下的信号，使其吸合换挡电磁阀，使电…     

波纹管碰撞性能的试验研究

对波纹管碰撞性能进行了比较详细的试验研究。试验结果表明：波纹管的吸能曲线比较平稳，是一个很好的汽车碰撞吸能部件，壁厚对于提高波纹管的吸能效果有很大的作用，动态冲击时的加速度比准静态时要高，且冲击速度越高，其承载能力也越强。     

电喷发动机燃油泵的4种基本控制电路

空气流量传感器带燃油泵开关的控制电路 量板式空气流量传感器内带有燃油泵开关(如丰田大霸王汽车)的燃油泵控制电路,如图1所示.在无空气进入气缸(测量板在初始位置)时,燃油泵开关6是断开的.当有空气进入气缸,测量板转动某一角度后,燃油泵开关6就处于接通状态.起动时,接通点火开关2(点火开关Ⅱ档),线圈L3通电,将燃油泵触点K2吸合(K1先于K2吸合),燃油泵5通电工作.     

强制沥青搅拌设备干燥滚筒振动原因分析及预防措施

通过对大吨位间歇式沥青搅拌设备干燥滚筒驱动原理介绍，分析了滚圈和托轮在机加工过程、装配过程中出现误差对干燥滚筒产生振动的影响。有针对性地实施预防，明确了干燥滚筒筒体与滚圈在装配时应采用的工艺基准，同时提出了干燥滚筒与托轮组装时以托轮为基准的优势。     

提高商用车操纵稳定性的研究

本文研究主动横向稳定器降低车身侧倾向，以及与后轴转向系统协调控制时，提高商用车操纵稳定性的效果，实车试验表明，采用前轮转角前馈控制方法，汽车转向时稳定器产生反侧力矩，大幅度地降低车身侧倾；当与后轴转向系统协调控制时，能够提高商用车的操纵稳定性。     

液压互联悬架抗侧倾控制研究（双语出版）

针对车辆减少能量消耗与提高抗侧倾能力需求,提出了一种主/被动可切换的液压互联悬架抗侧倾控制方法。基于9自由度车辆动力学模型,考虑蓄能器、液压缸、液压泵三者之间耦合的体积-流量-压力特性,建立液压互联悬架主动控制时域模型;结合"车身侧倾角-车身侧倾角速度"相平面法及车辆侧向加速度,得到车辆侧倾稳定域,并提出液压互联悬架系统侧倾稳定性控制介入与退出判据;在此基础上,采用Backstepping非线性控制算法设计主动液压互联抗侧倾控制器。最后,分析并改进侧倾稳定性评价指标,通过在MATLAB/Simulink环境下进行高速双移线、鱼钩试验等极端工况数值仿真,验证所提出的液压互联悬架主/被动切换控制系统能在减少能量消耗的情况下能否提高车辆抗侧翻的能力。研究结果表明：所提出的控制系统能有效提高车辆抗侧翻能力;当车辆侧倾状态超出设定的侧倾稳定区域介入线时,液压互联悬架系统由被动模式切换为主动抗侧倾模式,控制车辆侧倾状态回到稳定区域,以提高车辆侧倾稳定性;当判定车辆侧倾状态满足主动控制退出条件时,液压互联悬架系统回到被动模式,以减小能量消耗。     

Ride Vibration Measurements of Agricultural Tractor and Trailer Combinations

Tractor ride vibration levels have been measured when operating with and without a two wheel (2W) unbalanced and a four wheel (4W) balanced trailer. Measurements were made in the vertical, pitch, longitudinal and roll directions with the trailers unladen and laden over four typical farm surfaces

The results showed that tractor ride vibration levels were usually increased in all directions-particularly the longitudinal direction- when operating with the laden trailers. But for the unladen trailers, they were increased only in the longitudinal direction. Predominant tractor frequencies tended to be lower with the trailers attached, and coupling between the tractor longitudinal, vertical, roll and pitch co-ordinates was generally increased

Comparisons of the results with the trends predicted by a simplified theoretical model of a tractor and 2W trailer, suggested that the model should be extended to include, (a) the roll direction, (b) more realistic ground inputs, and (c) a 4W trailer     

某微型轿车后扭力梁式悬架K特性计算分析

为了获得横梁位置、扭力梁长度、初始定位参数这几个因素对整车性能的影响,本文建立了一种简化了的扭力梁式悬架模型,并根据这一模型计算出扭力梁式悬架的定位参数及侧倾中心高度。根据定位参数和侧倾中心高度的变化趋势来合理地选择扭力梁式悬架的设计参数。结果表明,横梁位于扭力梁中部时,定位参数匹配较好;扭力梁长度增加时对侧倾中心高度影响明显;初始外倾角对车辆性能的影响更明显。结论可以为扭力梁式悬架的设计计算提供参考。     

Ride Vibration Measurements of Agricultural Tractor and Trailer Combinations

SUMMARY

Tractor ride vibration levels have been measured when operating with and without a two wheel (2W) unbalanced and a four wheel (4W) balanced trailer. Measurements were made in the vertical, pitch, longitudinal and roll directions with the trailers unladen and laden over four typical farm surfaces

The results showed that tractor ride vibration levels were usually increased in all directions-particularly the longitudinal direction- when operating with the laden trailers. But for the unladen trailers, they were increased only in the longitudinal direction. Predominant tractor frequencies tended to be lower with the trailers attached, and coupling between the tractor longitudinal, vertical, roll and pitch co-ordinates was generally increased

Comparisons of the results with the trends predicted by a simplified theoretical model of a tractor and 2W trailer, suggested that the model should be extended to include, (a) the roll direction, (b) more realistic ground inputs, and (c) a 4W trailer     

Rollover mitigation for a heavy commercial vehicle

A heavy commercial vehicle has a high probability of rollover because it is usually loaded heavily and thus has a high center of gravity. An anti-roll bar is efficient for rollover mitigation, but it can cause poor ride comfort when the roll stiffness is excessively high. Therefore, active roll control (ARC) systems have been developed to optimally control the roll state of a vehicle while maintaining ride comfort. Previously developed ARC systems have some disadvantages, such as cost, complexity, power consumption, and weight. In this study, an ARC-based rear air suspension for a heavy commercial vehicle, which does not require additional power for control, was designed and manufactured. The rollover index-based vehicle rollover mitigation control scheme was used for the ARC system. Multi-body dynamic models of the suspension subsystem and the full vehicle were used to design the rear air suspension and the ARC system. The reference rollover index was tuned through lab tests. Field tests, such as steady state cornering tests and step steer tests, demonstrated that the roll response characteristics in the steady state and transient state were improved.     

Application of Aerodynamic Actuators to Improve Vehicle Handling

This exploratory study considers applications of active aerodynamic devices for suppressing parasitic motion and for improving the response of vehicles to steering, within the scope of the linear dynamic behaviour. A three DOF linear model is chosen to describe the side slip, yaw and roll motion of a baseline front-wheel steered vehicle. The improvements in performance of the base-line vehicle that are achievable by the application of direct yaw and roll moments are determined when either an open loop control pre-filter or a state feedback control law based on LQR design is applied. Unlike the former control, the state feedback control is unable to make the body side-slip angle vanish. The feedback control performance of each of the two moment actuators has been examined separately and then jointly. The advantages of combining the open loop and feedback dual actuator configurations are demonstrated using the two-degree of freedom control scheme. It is found that the scheme yields a spectacular performance but demands unreasonably large moments from the actuators in the context of available aerodynamic forces. On the other hand, the demand on direct yaw and roll moment of actuators is modest when the actuators are controlled using the LQR feedback only and if the control design is used to track a desired yaw rate trajectory and simultaneously to reduce the parasitic rolling motion. Significant improvements in handling and dynamic stability of a base-line vehicle can be achieved by aerodynamically generated direct yaw and roll actuator moments provided the target control performance is reasonable. The configurations of aerodynamic actuators considered are feasible for improving vehicle handling in cornering on motorways but more work remains to be done to explore alternative aerodynamic configurations that give rise to less side effects and higher lift coefficients.     

Application of Aerodynamic Actuators to Improve Vehicle Handling

This exploratory study considers applications of active aerodynamic devices for suppressing parasitic motion and for improving the response of vehicles to steering, within the scope of the linear dynamic behaviour. A three DOF linear model is chosen to describe the side slip, yaw and roll motion of a baseline front-wheel steered vehicle. The improvements in performance of the base-line vehicle that are achievable by the application of direct yaw and roll moments are determined when either an open loop control pre-filter or a state feedback control law based on LQR design is applied. Unlike the former control, the state feedback control is unable to make the body side-slip angle vanish. The feedback control performance of each of the two moment actuators has been examined separately and then jointly. The advantages of combining the open loop and feedback dual actuator configurations are demonstrated using the two-degree of freedom control scheme. It is found that the scheme yields a spectacular performance but demands unreasonably large moments from the actuators in the context of available aerodynamic forces. On the other hand, the demand on direct yaw and roll moment of actuators is modest when the actuators are controlled using the LQR feedback only and if the control design is used to track a desired yaw rate trajectory and simultaneously to reduce the parasitic rolling motion. Significant improvements in handling and dynamic stability of a base-line vehicle can be achieved by aerodynamically generated direct yaw and roll actuator moments provided the target control performance is reasonable. The configurations of aerodynamic actuators considered are feasible for improving vehicle handling in cornering on motorways but more work remains to be done to explore alternative aerodynamic configurations that give rise to less side effects and higher lift coefficients.     

Enhancing roll stability of heavy vehicle by LQR active anti-roll bar control using electronic servo-valve hydraulic actuators

Rollover of heavy vehicle is an important road safety problem world-wide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss is the main cause of rollover accidents in which heavy vehicles are involved. In order to improve the roll stability, most of modern heavy vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. However these may be not sufficient to overcome critical situations. This paper introduces the active anti-roll bars made of four electronic servo-valve hydraulic actuators, which are modelled and integrated in a yaw-roll model of a single unit heavy vehicle. The control signal is the current entering the electronic servo-valve and the output is the force generated by the hydraulic actuator. The active control design is achieved solving a linear optimal control problem based on the linear quadratic regulator (LQR) approach. A comparison of several LQR controllers is provided to allow for tackling the considered multi-objective problems. Simulation results in frequency and time domains show that the use of two active anti-roll bars (front and rear axles) drastically improves the roll stability of the single unit heavy vehicle compared with the passive anti-roll bar.