Abstract: The usage of the seatbelt as a part of the vehicle protection system has immensely promoted occupant safety. However, recent accident investigation shows that it is necessary to increase the chest injury protective efficiency in frontal impact condition. The study is conducted by using baseline human body FE model in combination with frontal impact test. An occupant restraint system model of Dynamic Lock Tongue (DLT) seatbelt is established and verified by vehicle experiments. The study aims to the influence of DLT on occupant chest injury. The results show that DLT can block the movement of the webbing from the chest to the hips, and reduce the dummy chest displacement, thus effectively reducing the pressure on the chest of the occupant and the amount of occupant chest compression. DLT effectively reducing the amount of occupant chest compression, which affects the C-NCAP score. Therefore, DLT should be fully considered and applied for developing the high safe performance of vehicles in the design stage.

Key words: Seat belt; Dynamic lock tongue; Chest displacement; Frontal impact

摘要： 安全带的逐步使用极大地提高了车内乘员的安全性，但近年的交通事故研究表明，乘员胸部损伤在正面碰 撞过程中的防护效率需进一步改善。利用已验证生物逼真度的人体有限元模型和正面碰撞试验结果，建立配有动态 锁止舌片（Dynamic Lock Tongue，DLT）安全带的乘员约束系统分析模型，研究 DLT 对乘员胸部损伤的影响，并 通过整车实验进行了验证。结果表明，DLT 可以阻止织带从胸部到臀部的移动，减小假人胸部位移量，从而有效 地降低乘员胸部所承受的压力和乘员胸部压缩量。DLT 有效降低乘员胸部压缩量，从而影响 C-NCAP 得分。因此， 在整车安全性能设计阶段，应充分考虑使用 DLT，以开发出满足安全性能的车辆。

关键词: 安全带；锁止舌片；胸部压缩量；正面碰撞