膝盖防护用材料动态缓冲性能研究

Study of the Dynamic Buffering of Knee Protective Material for the Elderly

为研究老年人摔倒时膝盖部位的防护装置,探讨经编间隔织物和聚氨酯海绵的动态缓冲性能。采用改进后的动态冲击方法模拟老年人摔倒时的受力情况,通过分析接触刚度系数,冲击力与位移曲线,冲击力与时间曲线,以及冲击能量与时间曲线反映材料的动态缓冲性能。此外,通过定义缓冲系数进一步表征试样缓冲性能,并分析试样的结构参数和缓冲系数之间的关系。结果表明,一定硬度的聚氨酯海绵具有较好的能量吸收性能,通过聚氨酯海绵和经编间隔织物的复合可得到缓冲性能较好的材料。

In order to study the knee protector used for the elderly against falling clown accidendy, the paper discusses the dynamic buffering performance of warp knitted spacer fabric and polyurethane sponge. The new impact testing method is designed to simulate the behavior of falling down, According to analyzing the contact stiffness co- efficient, the impact-displacement curves, the impact-time curves and impact energy-time curves, the dynamic buffering performance of materials is described. In addition, the buffering coefficient is used to reflect the buffering performance, and the relation between the structure parameters and the buffering coefficient are recorded and analyzed. The results show that, the polyurethane sponge with appropriate grams per square meter has good buffer performanee, and the optimized combination of warp knitted spaced fabric and sponge material can give much better buffer performance.