滚筒轴距可调的汽车制动检验台研究

发布时间：2018-04-11 19:00

本文选题：汽车 + 滚筒轴距可调　；参考：《山东大学》2016年硕士论文

【摘要】：汽车制动性能台试检验已成为检测汽车制动系统技术状况、保障汽车运行安全的主要技术手段。为真实反映车辆满载时制动性能,研究汽车制动性能台式加载检测方法,对有效开展车辆满载制动性能检测具有重要意义。围绕轴距可调的反力式汽车制动检验台,本文开展以下研究工作：开发了能自动检测车轮直径、调节滚筒轴距的新型反力式汽车制动检验台,对检验台的结构参数进行了描述,并对检验台进行动力学分析,研究了滚筒高度差和安置角对制动力测量结果的影响规律；提出车轮直径计算模型,根据第三滚筒转角位置自动计算车轮直径,结合设定的安置角,计算滚筒间轴距并通过液压装置进行调整和张紧；利用开发的试验台进行了实车测试,结果表明,开发的新型制动检验台可通过调节滚筒轴距,模拟改变汽车轮荷,有效检测车辆制动力。对车辆轴荷、滚筒高度差、安置角、滚筒表面附着系数、轮胎气压、制动力信号采样频率和司机驾驶操作对制动检验台检测精度的影响规律进行了测试分析,实车测试结果表明,调节滚筒轴距和改变轮胎气压对制动力检测结果有显著影响。对举升加载制动检测方法进行了研究,分析了举升加载制动原理及测试方法,结果分析表明两轴汽车不适宜采用举升加载方法,对于多轴货车中间轴采用举升加载的方式可有效测出车辆制动力；对拉压张紧式加载制动检测方法进行了研究,分析了拉压张紧式加载制动原理及测试方法,分析认为适应各种车型；对调整轴距式加载制动检测方法进行了研究,分析了调整轴距式加载制动原理及测试方法,分析认为两轴车、三轴及三轴以上的多轴货车、采用并装双轴及并装三轴挂车的所有车轴,采用调整轴距加载的方式都可有效测出车辆制动力；最后对举升加载制动检测方法、调整轴距式加载制动检测方法和拉压张紧式加载制动检测方法进行了比较分析。为了准确测试汽车制动器性能,构建了制动检验台摩擦损失模型,以对制动力检测结果进行修正。定义了相对滑移量,基于相对滑移量和安置角,构建了反力式制动检验台摩擦损失模型,该模型可为车辆制动器制动力修正摩擦损失提供依据。为提高滚筒反力式制动检验台检测结果的准确性,应对安置角变化引起的摩擦损失进行修正后,再根据GB7258-2012和GB 21861-2014对车辆制动率进行判别。
[Abstract]:The bench test of automobile braking performance has become the main technical means to detect the technical condition of automobile braking system and to ensure the safety of automobile operation.In order to truly reflect the braking performance of a vehicle at full load, it is of great significance to study the detection method of vehicle braking performance under desktop loading, which is of great significance for the effective detection of vehicle full load braking performance.In this paper, the following research work is carried out: a new type of counterforce brake test bench is developed, which can automatically detect the diameter of the wheel and adjust the roller wheelbase, and describes the structural parameters of the test table.The influence of roller height difference and placement angle on the braking force measurement results is studied, and the wheel diameter calculation model is proposed, which automatically calculates the wheel diameter according to the position of the third drum rotation angle.Combined with the setting angle, the wheelbase between the rollers is calculated and adjusted and tensioned by hydraulic device. The test results show that the new brake test bench can be adjusted by adjusting the roller wheelbase.The simulation changes the wheel load of the vehicle and effectively detects the braking force of the vehicle.The influence of vehicle axle load, roller height difference, placement angle, surface adhesion coefficient, tire pressure, sampling frequency of braking force signal and driver's driving operation on the precision of brake test table are tested and analyzed.The test results show that adjusting the roller wheelbase and changing the tire pressure have a significant effect on the braking force test results.The testing method of lifting load braking is studied, and the principle and test method of lifting load braking are analyzed. The results show that the lifting loading method is not suitable for two axle vehicles.The braking force of the vehicle can be effectively measured by lifting and loading the intermediate shaft of the multi-axle freight car, the testing method of the tension and compression tension loading brake is studied, and the principle and the test method of the tension tension loading brake are analyzed.It is considered that it is suitable for all kinds of vehicle models, the detection method of adjusting wheelbase loading brake is studied, the principle and test method of adjusting wheelbase loading braking are analyzed, and the analysis shows that the two axle truck, three axle truck and more than three axle truck,The braking force of the vehicle can be effectively measured by means of adjusting the wheelbase loading with all the shafts of the dual axle and three axle trailers installed in parallel. Finally, the brake detection method of lifting loading is used.The detection methods of adjusting wheelbase loading brake and tension tension loading brake are compared and analyzed.In order to accurately test the performance of automobile brake, the friction loss model of brake test table is constructed to correct the test result of braking force.The relative slip is defined. Based on the relative slip and the placement angle, the friction loss model of the counterforce brake test table is constructed. The model can provide the basis for the brake force modification of the friction loss of the vehicle brake.In order to improve the accuracy of the test results of the roller counterforce brake test table, the friction loss caused by the change of the placement angle should be corrected, and then the braking rate of the vehicle should be judged according to GB7258-2012 and GB21861-2014.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U467.52

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