小型装载机FOPS受落锤冲击的动态响应

为了提高小型装载机防落物保护装置(FOPS)的抗冲击性，讨论了FOPS受标准落锤冲击的破坏现象，提出应用显式动态有限元法解决小型装载机FOPS的冲击响应。以ZL15装载机为例给出了有限元模型的建立方法和边界条件的施加方法。分析了落锤碰撞FOPS时的冲击力波形、FOPS的冲击变形规律和能量转换规律。结果表明：冲击力波形与方波假设不同；冲击过程没有FOPS构件侵入DLV，FOPS满足ISO3449的要求；第一次冲击FOPS吸收了83%的能量，第二次及其以后的冲击可以忽略。在冲击能量不变的前提下，分析了落锤高度和质量变化对FOPS冲击变形的影响规律。结果表明：落锤高度变小、质量变大时冲击变形反而变大。

Dynamic impact response of minitype wheel loader FOPS subjected to drop hammer collision

In order to improve the impact resistance of minitype wheel loader FOPS, the breakage phenomenon when the FOPS was impacted by the standard drop hammer was discussed, and the method of explicit dynamic finite element was put forward to solve the impact response of minitype wheel loader FOPS. ZL15 wheel loader was taken as an example to illustrate the methods for establishing finite element model and applying boundary conditions. The impulse force waveform, the rule of impact deformation and the rule of energy conversion were analyzed to indicate that the impulse force waveform was different from the hypothesis of square wave. No FOPS components invaded DLV during being impacted; the FOPS met the standard of ISO3449. The FOPS absorbed 83% of energy at the first impact, and the impact thereafter can be neglected. The rule of the drop hammer height and the change of mass were analyzed given a constant impact energy. It indicated that the impact deformation became larger with the decrease of the hammer height and the increase of mass.