通过一个专门设计的试验,揭示了切削颤振从产生到剧烈的全过程:颤振会在一个特定的切深下发生在一个特定的频率上;随着切深的加大,该频率上的振幅会逐渐增大;当切深达到另一个特定值时,剧烈的颤振会导致工件与刀具的短暂脱离;当切深继续加大时,颤振频率降低到一个新的频率上并保持不变。通过激振试验,确认了这2个颤振频率分别是工件系统和刀具系统的固有频率。从颤振能量补充和质量效应的角度分析,颤振应发生于2个最终执行部件之一。建立了一个具有2个颤振主动体的颤振模型,该模型更适合颤振监测和抗颤振结构改良的需要。
Through a specially designed chatter vibration test for machine tools in which the chatter occured and expanded, the complete process was exposed. Chatter occurred on a given frequency at a given cutting depth. The chatter extent increased synchronously as the cutting depth was gradually increased. When cutting depth reached another special value, violent chatter led the cutting tool to break away transitorily from the work piece. While the cutting depth continually increased, chatter frequency moved downwards and remained un changed. Through an excitation test, it was confirmed that the two frequencies obtained experimentally were the natural frequencies of work piece and cutting tool systems. Regarding chatter energy supply and mass effect, the chatter would occur on one of the two final executive components at a given natural frequency. A new chatter model with two chatter active bodies was proposed. This model can be applied to monitor the chatter and improve the structure of the components.