高速卧式加工中心主体结构试验模态分析

Experimental Modal Analysis to the Main Structure of High-speed Horizontal Machining Center

对高速卧式加工中心主体结构进行试验模态测试,得到了主体结构的各阶固有频率、阻尼比、刚度等模态参数以及模态振型.通过分析其动态特性,确定了机床结构的薄弱环节是主轴前端轴承处及近丝杠立柱,给出了结构改进措施;并且,通过分析主轴前端动刚度,确定了影响机床加工稳定性的目标模态,为进一步提高机床加工效率提供了可靠的改进依据.分析结果表明:试验模态分析技术是提高机床抗振性能和加工稳定性的有效方法.

By the experimental modal testing to the main structure of a high-speed horizontal machining center, the modal parameters such as the natural frequency, damping ratio, stiffness and mode shapes are obtained. By analyzing the dynamic characteristics, the weak links of this structure is at the spindle front bearing and the vertical column on which the screw driving the spindle box to move in vertical direction is mounted are determined, and provide an important basis of optimizing the structure for the machining center. And the amplitude-frequency characteristic curves of the weak structure evaluate the dynamic stiffness as the key indicators to provide reliable data for improving processing accuracy and cutting ability of machining center. The analysis results show that experimental modal analysis is a effective test method for improving the anti-vibration performance and machining stability of domestic machining centers.