本世纪30年代起,各国先后出现了高速公路,车辆时速分别提高到100至140公里之间不等,个别国家规定,在高速公路上行驶的车辆不受速度限制,但随之而来的是,追尾交通事故时有发生,在交通事故伤亡人员中又增添了一种伤亡新形式─—颈部损伤。 高速运行的汽车发生多车追尾交通事故时,除最先、最后两部车辆驾驶和乘车人外,中间车上的所有司乘人员,都要受到多次前后“夹击”,来自背后的冲击力最大,背部尚有靠背倚托,而颈部至头部却处在“悬空”状态下,由于反复“剪切(折)”的作用力和冲击力的突至及瞬间消失,致使人的颈部最容易造成损伤,甚至造成死亡。由此人们才设想并制成了供司乘人员乘坐的高靠背,同时考虑到乘车人员身高的不同,又在高靠背上端设置了可伸缩的“枕头“,近年我国生产的大小客车也都置备了靠背上的“枕头”,专供头部倚靠,加之系好安全带后,一旦发生车辆追尾事故,在一般情况下,司乘人员的颈部和头部也不致受损伤,由此引起的伤 Since the 1930s, the expressways have appeared in various countries and the speed of vehicles has been raised to between 100 and 140 kilometers per hour respectively. Some countries have stipulated that the vehicles traveling on the freeways should not be subject to speed restrictions. However, , Rear-end traffic accidents have occurred from time to time, and a new form of casualty has been added to casualties among traffic accidents ─ ─ neck injuries. In the event of a multi-car rear-end collision at a high-speed car, all drivers and crew members in the car except the first and last two vehicles are subject to repeated “attack” and “back-attack” The maximum force, the back still backrest, and the neck to the head is in a “dangling” state, due to repeated “shear (off)” force and impact suddenly and instantly disappear, resulting in human The neck is most likely to cause injury, and even cause death. As a result, people only envisioned and made a high backrest for passengers and passengers taking into account the different height of riders, and set up retractable “pillows” on the upper end of the high backrest. In recent years, both the size passenger cars produced in China and the passenger cars Provision of a “pillow” on the backrest, dedicated to the head leaning, coupled with fasten the seat belt, in the event of rear-end vehicle accident, under normal circumstances, the Secretary’s staff neck and head are not damaged, which caused The injury