共查询到19条相似文献,搜索用时 504 毫秒
1.
2.
3.
通常在新车行驶几百公里或更换新的制动盘后的一段行驶里程内,由于制动盘端面跳动公差超标造成制动轮泵回推.形成周期性的液压回推压力波动.导致脉动制动效果。同时由于脉动制动产生的高温.使制动盘内应力释放.造成制动盘变形,引起制动踏板加剧抖动或转向盘振动。另外.车辆长期存放会使制动盘生锈,而且由于盐砾的化学作用.造成制动盘表面精糙不平.影响制动效果。其次.常常由于厚积的道路尘垢、油脂、制动屑和基体铁锈形成一层摩擦系数不同于先前的表层,造成对应两轮制动盘的摩擦力不对等.引起制动跑偏.有时还伴随尖锐的噪声。 相似文献
4.
为了在实车上客观评估制动抖动的强度,在制动抖动传递路径的理论基础上确认振动传感器的实车布置方案并进行相关的整车测试,对测量的数据信号进行时域、频率和阶次分析。基于数据处理分析的结果可以证实制动抖动的整车试验方案是可行的,制动抖动会向制动踏板、车身底板和转向盘进行传递且转向盘处的振动强度明显高于制动踏板和车身地板。随后选取转向盘Y向的振动强度作为考核指标,分析了制动盘的初始制动温度、厚薄差及测试速度对整车制动抖动的影响。 相似文献
5.
2008年4月开始,凯美瑞2.40G轿车制动抖动故障呈突然上升趋势,并持续5个月为多发故障.制动抖动是指在制动时,车身、仪表台、方向盘、制动踏板等出现振动的现象.100km/h左右高速时抖动主要出现在车身、仪表台、转向机构、车轮上.50km/h以下低速时抖动发生在制动踏板上.
一、制动抖动产生的原因
1.制动盘的厚度差
制动盘的厚度差是指转动制动盘一周厚度的变动量.(最大厚度-最小厚度)如图1所示. 相似文献
6.
7.
8.
9.
基于某车型持续出现的低里程制动抖动现象的调查研究,分析了该车型出现低里程制动抖动的可能性原因。通过盐雾处理模拟制动盘自然锈蚀过程,并实车路试再现了该车型低里程制动抖动发生过程,提出了制动面生锈不均匀是造成低里程制动抖动的主要原因的结论。 相似文献
10.
盘式制动器的制动抖动现象,会影响车辆的行驶安全性和驾驶舒适性,其产生原因是制动盘的原始几何尺寸及热膨胀作用造成几何变形的共同作用引起制动压力的波动,进而产生对制动系统及悬架和转向机构的激振作用。制动管路和悬架等传递途径的自振特性,也会对抖动的振幅产生影响。文章在结合国内外相关文献和实验分析数据的基础上,对盘式制动器特有的制动抖动现象进行了研究。主要包括制动抖动现象的成因和相关各方面的实验与分析方法,最后提出了改进建议。 相似文献
11.
12.
K. S. Sim J. H. Lee T. W. Park M. H. Cho 《International Journal of Automotive Technology》2013,14(4):587-594
Brake judder is abnormal vibration, which is mainly generated by uneven contact between the brake disc and pad. The abnormal vibration from BTV (Brake Torque Variation) is transferred to the suspension and the steering system during braking. In this paper, judder simulation is carried out using a multi-body dynamic analysis program to analyze the relationship between judder and the transfer mechanism, which consists of the suspension and the steering system. In order to verify the analytical model, test results are compared with the simulation results. A sensitivity analysis is also carried out. In addition, an optimization method is presented for judder reduction, using the design of experiments. 相似文献
13.
Hot judder simulation of a ventilated disc and design of an improved disc using sensitivity analysis
J. H. Park T. W. Park J. H. Lee M. H. Cho 《International Journal of Automotive Technology》2014,15(1):1-6
In a disc brake system, thermal expansion of the material is caused by friction energy that is generated by the sliding contact between a disc and pad during braking. This phenomenon, thermo-elastic instability, can lead to hot spots on the disc surface and a hot judder phenomenon. Transient finite element analysis has been used to simulate this phenomenon. Three dimensional finite element models of a disc, pad, and cylinder were created. Each part was connected by a joint. Contact condition was applied to the disc and pad with a friction coefficient (μ) of 0.4. A convective heat transfer coefficient was set as 40 W/m2K. Using a commercial program SAMCEF, the simulation of the thermo-mechanically coupled system was performed. In order to find the sensitive parameters of brake judder, sensitivity analysis was carried out with consideration for disc design parameters. As a result, the hot spot phenomenon was confirmed and hot judder was predicted. Moreover, the more sensitive parameters of the hot judder phenomenon were presented. Finally, an improved disc model and an analysis technique were verified by comparison to dynamo test results. 相似文献
14.
15.
S. -H. Kim E. -J. Han S. -W. Kang S. -S. Cho 《International Journal of Automotive Technology》2008,9(2):233-247
This paper investigates the brake corner system to reduce brake torque variation in the brake judder problem. A numerical
model for determining brake torque variation was constructed using the multi-body dynamics model. Using this model, the brake
torque variation for a given disc thickness variation was obtained in the time domain. The multi-body dynamics model was verified
by a dynamometer test via the comparison of brake torque variation and load distribution patterns of the pad. To reduce the
simulation time and cost required to determine factors that influence the reduction in brake torque variation, a simple mathematical
model was constructed and used to determine both the brake torque variation and influential factors. The multi-body dynamics
model and dynamometer test were modified on the basis of the results of the simple mathematical model and deformed shape of
the multi-body dynamics model. These influential factors were verified to reduce the brake torque variation. 相似文献
16.
鼓式制动器结构振动噪声研究 总被引:3,自引:1,他引:3
本文阐述了制动器制动噪声发生的一般机理,给出了鼓式制动器低频(发啃)和高频(尖叫)振动噪声的实际结构闭环耦合模型,较为完善地考虑了各种结构系数的影响。模型的仿真分析结果和试验结果取得良好一致。提高了对制动噪声的定量分析,证明了通过改变结构的特性参数匹配可有效地抑制制动噪声的发生。 相似文献
17.
18.