细长轴切削的非线性系统动力稳定性分析  

Nonlinear Dynamics Stability Analysis of Cutting a Slender Shaft

作　　者：丛春晓[1] 刘恒[1] 吕凯波[1] 景敏卿[1] 

机构地区：[1]西安交通大学机械电子及信息系统研究所,西安710049

出　　处：《组合机床与自动化加工技术》2011年第10期40-44,48,共6页Modular Machine Tool & Automatic Manufacturing Technique

基　　金：国家机床重大科技专项(2009ZX04001-071);国家自然科学基金面上项目(51075315);轴研所主轴项目(2010ZX04012-014);国家973计划项目(2007CB707705);国家863计划项目(2007AA04Z432)

摘　　要：为了研究细长轴切削过程中的振动特征以及稳定性,运用轴承转子非线性分析理论研究非线性滚动轴承力和非线性切削力作用下的系统稳定性及失稳分叉规律。建立了非线性切削力模型和细长轴的有限元分析模型。通过周期解、Poincaré截面映射图确定系统的运动特性。经过计算,系统的失稳分叉方式是同步周期解经Hopf型伪周期分叉产生伪周期解。与空转情况相比,切削状态下的细长轴分叉点转速下降近80%,且其分叉点转速范围较窄。在系统参数中,稳定性规律对转轴长径比和轴承刚度的变化比较敏感。通过双主轴驱动的细长轴切削实验可以得出,失稳前后系统的频率变化特征和运动形态与计算结果一致。为提高切削稳定性,失稳颤振的预测和监测提供理论依据。To study the vibration characteristics and stability while cutting a slender shaft,the system＇s stability and bifurcation are researched under the effect of the nonlinear ball bearing force and the cutting force using the nonlinear dynamics analysis theory of rotor bearing system.The nonlinear cutting force model and finite element analysis model of slender shaft are established.The system＇s motion characteristics are determined by the periodic solution and Poincaré maps.The analysis result shows that system＇s instability bifurcate way is the synchronized periodic solution turn into quasi-periodic solution through Hopf quasi-periodic bifurcation.The speed of bifurcation point in cutting condition is reduced by 80% compared to no cutting system,and the speed has small change.Stability rules are more sensitive to the stiffness on bearings and length-diameter ratio changes on shaft.The frequency and motion characteristics in stable and unstable experiments agree well with the theory results.Which provides the theory basis for prediction and monitoring of chatter.

关 键 词：细长轴 非线性动力特性 稳定性 分叉 

分 类 号：TG519.1[金属学及工艺—金属切削加工及机床] O347.6[理学—固体力学]