XK713数控镗铣床整机静动态特性分析

Static and Dynamic Characteristic Analysis of XK713 NC Boring-milling Machine

为了更准确地预测和分析机床整机的静动态特性,建立的机床整机有限元模型必须包含各结合面特性参数。以XK713数控镗铣床为例,运用有限元法将各结合面特性参数融合到整机模型中,建立包含结合部特性的机床整机动力学模型。在此基础上,利用谐响应分析法计算刀具与工件之间的相对刚度。与同类机床相比,XK713数控镗铣床三向静刚度都较高,但y向静刚度相对较小;x向刀具与工件相对振幅较大,y向的谐响应频率最丰富。因此在使用中要注意避开优势固有频率,在改进设计时要注意提高y向静刚度和x向动刚度。

Adding characteristic parameters to each pair of the combined interfaces must be considered at building finite element model in order to get an accurate prediction and analysis of static and dynamic characteristics of the whole machine.Taking XK713 NC boring-milling machine as an example,integrating the combined interface parameters into the whole machine model with the help of finite element method,the dynamic model contained combined interface characteristics of the whole machine was built.On this basis,the relative stiffness between the tool and the workpiece was analyzed by using harmonic respond analyzing method.The conclusions are that XK713 NC boring-milling machine has bigger static stiffness in three directions as compared with other similar machines,but with a relatively smaller static stiffness in y direction,a relative bigger vibration amplitude between the tool and the work-piece in x direction and most intensive harmonic respond frequency in y direction.Therefore preponderant inherent frequency should be avoided in usage,and the static stiffness in y direction and the dynamic stiffness in x direction should be paid attention to in improvement of design.