安全带卷收器锁止性能研究及结构强度分析

发布时间：2018-06-23 04:23

本文选题：安全带卷收器 + 锁止机构　；参考：《重庆大学》2016年硕士论文

【摘要】：由于我国人口众多,道路交通设施落后,车辆自身安全性能较差,这些因素综合起来造成了交通事故的频发。安全带作为汽车被动安全中最有效的防护装置,在发生事故时起着十分重要的保护作用。目前,国内外对于汽车安全带的研究主要是基于乘员约束系统方面,应用多刚体动力学方法,仿真分析安全带系统对假人身体不同部位的损伤情况,而对安全带卷收器部件的结构性能研究较少。本文通过紧急锁止式卷收器,对带感和车感机构的锁止性能进行参数分析,并对卷收器支架进行结构强度分析和优化改进,以此综合提高安全带卷收器的紧急锁止性能和约束抗载能力。首先,本文介绍了汽车安全带的发展历程以及国内外企业的技术研究状况。同时本文概述了安全带的种类、用途,并掌握了目前应用最普遍的紧急锁止式卷收器的构成和工作原理。通过对汽车安全带国标的解析,熟知了安全带卷收器的锁止性能和结构强度要求。其次,对安全带卷收器中的带感锁止机构和车感锁止机构建立了动力学参数模型。对于带感锁止机构,通过产品实例分析,得出压簧的刚度、初始压缩量和压簧作用力距离等参数对机构的锁止加速度均有较大影响的结论。进而利用MATLAB软件对模型的参数进行了优化,找到符合锁止条件的最优解。对于车感锁止机构,将推导的理论方法运用到实例中,经计算发现车感臂内表面倾角的变化对车感锁止减速度影响很小,而车感座凹槽面倾角对锁止减速度的变化起着关键的作用。通过计算分析给出了车感座凹槽倾角的设计范围,为今后车感机构的设计提供一定的参考。最后,对卷收器的强度失效形式进行了介绍,得到了支架的结构强度对卷收器总成的安全稳定起着决定性作用的结论。故应用ABAQUS对卷收器模型进行有限元分析,得出了支架中最先破裂失效的区域为螺栓孔附近区域的结果。结合分析结果和工程经验,对螺栓孔及其它变形较大的区域采用局部结构改形和增加筋的方法,得到了强度更高的支架优化方案。在章节内容的最后,对安全带系统中的织带、D环、固定点、带扣等结构的失效形式也进行了简要的分析。全文重点对卷收器的锁止性能和支架结构强度两个方面进行了研究,提高了安全带的安全性能,减小了汽车被动安全失效对乘员生命造成伤害的可能性。
[Abstract]:Because of the large population, backward road traffic facilities and poor safety performance of vehicles, these factors have resulted in frequent traffic accidents. As the most effective protective device in passive safety, seat belts play a very important role in the protection of accidents. At present, the domestic and foreign researches on seat belts are mainly based on the occupant restraint system. The multi-rigid body dynamics method is used to simulate and analyze the damage of the seat belt system to different parts of the dummy body. However, there is little research on the structural performance of the seatbelt retracer. In this paper, through the emergency locking winder, the locking performance of the sensor and the car sense mechanism is analyzed, and the structural strength analysis and optimization improvement of the winch bracket are carried out. In this way, the emergency locking performance of the seatbelt retractor and the ability to restrain the load are improved. First of all, this paper introduces the development of automobile seat belt and the technical research status of domestic and foreign enterprises. At the same time, this paper summarizes the types and uses of seatbelts, and grasps the structure and working principle of the most common emergency locking reel. The locking performance and structural strength requirements of the seatbelt retractor are well known through the analysis of the national standard of the seat belt. Secondly, the dynamic parameter model of the safety belt retracer is established. Through the analysis of product examples, it is concluded that the stiffness, initial compression and force distance of the spring have great influence on the locking acceleration of the mechanism. Then the parameters of the model are optimized by MATLAB software, and the optimal solution is found. For the car sense locking mechanism, the theoretical method is applied to an example. It is found that the change of the inclination angle of the inner surface of the car sensing arm has little effect on the deceleration speed of the car sense lock. The angle of inclination of the grooves plays a key role in the change of lock deceleration. Through the calculation and analysis, the design range of the inclination angle of the grooves of the car seat is given, which provides a certain reference for the design of the car sensing mechanism in the future. Finally, the failure mode of the winder strength is introduced, and the conclusion that the structural strength of the bracket plays a decisive role in the safety and stability of the winder assembly is obtained. So the finite element analysis of the winder model is carried out by Abaqus, and the results show that the first failure area of the support is the area near the bolt hole. Based on the analysis results and engineering experience, the method of local structural modification and reinforcement is adopted for bolted holes and other areas with large deformation, and the optimum scheme of support with higher strength is obtained. At the end of the chapter, the failure forms of belt D ring, fixed point and buckle are also analyzed briefly. In this paper, the locking performance of the winder and the structural strength of the bracket are studied in order to improve the safety performance of the seat belt and reduce the possibility of the passive safety failure of the vehicle causing harm to the occupant's life.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U491.61

【参考文献】