高速铁路道岔数控龙门铣床的尺寸优化研究

Size optimization for CNC gantry milling machine of high speed railway turnout

针对高速铁路道岔数控龙门铣床基频偏低的问题,以机床整机为研究对象,对其主体结构的动态特性进行了研究,提出了一种基于灵敏度分析的尺寸优化方法。通过对机床主体结构的模态分析和谐响应分析,得到了机床的前10阶固有频率、振型以及幅频响应曲线,并找到了机床结构的薄弱环节;然后对机床进行了灵敏度分析,根据分析结果中各参数对质量与固有频率的敏感程度,选出了机床结构的关键尺寸,随后对机床关键尺寸进行了尺寸优化。研究结果表明:优化后,机床的固有频率得到了提升,并且成功避开了共振频率,可满足机床的设计要求。

Aiming at the problem that the base frequency of CNC planer milling machine of high speed railway turnout is low taking the ma chine tool as the research object the dynamic characteristics of its main structure were studied and a dimension optimization method based on sensitivity analysis was proposed. Through modal analysis and harmonious response analysis of the main structure of the machine tool the first ten order natural frequency vibration mode and amplitude frequency response curve of the machine tool were obtained and the weak links of the machine tool structure were found. Then the sensitivity analysis of the machine tool was carried out. According to the sensitivity degree of each parameter to the quality and natural frequency in the analysis result the key size of the machine tool structure was selected and then the key size of the machine tool was optimized. The results indicate that after optimization the natural frequency of the machine tool is improved and the resonance frequency is avoided successfully which meets the design requirements of the machine tool.