精铣削中抑制柔性工件颤振的阻尼器设计

针对精铣削过程中柔性工件的颤振抑制问题,提出了一种利用空气黏性的新型被动质量阻尼器。首先,该质量阻尼器由一个可在薄壁壳体内自由移动的圆柱形重物组成,通过重物和壳体之间的适当间隙提供了密集的能量耗散;其次,给出了该阻尼器的理论模型,并提出了一种合理的宽带调谐策略,使该阻尼器能够在较宽的工作范围内通过固定调谐来提供足够的阻尼效率。通过冲击实验和铣削实验对该阻尼器进行了有效性验证。结果表明:该阻尼器的临界轴向切削深度显著增加约100倍;与同等质量颗粒阻尼器相比,该阻尼器的阻尼效率明显提升,过度切削量减少了14倍;与传统调谐质量阻尼器相比,该阻尼器的峰值效率更小,但工作范围更大,因此适用于细长柔性工件的铣削加工。

Design of Damper for Chatter Suppression of Flexible Workpiece in Fine Milling

Aiming at the problem of chatter suppression of flexible workpiece in finishing milling,a new type of passive mass damper based on air viscosity was proposed.Firstly,the mass damper was composed of a cylindrical weight which can move freely in a thin-walled shell,which provides dense energy dissipation through a proper gap between the weight and the shell.Secondly,the theoretical model of the damper was given,and a reasonable broadband tuning strategy was proposed,so that the damper could provide sufficient damping efficiency through fixed tuning in a wide working range.The effectiveness of the damper was verified by impact test and milling test.The results show that the critical axial cutting depth of the damper is significantly increased by about 100 times.Compared with the particle damper with the same mass,the damping efficiency of the damper is obviously improved,and the excessive cutting amount is reduced by 14 times.Compared with the traditional tuned mass damper,the damper has smaller peak efficiency,but wider working range,so it is suitable for milling slender flexible workpieces.