Bending Vibration Analysis of Tensioned Ball Screw under Nonuniform Stress during the Cutting Process

摘要

The bending vibration of tensioned ball screw under nonuniform stress in the cutting process is analyzed in this paper. Differential equation of a beam under nonuniform prestress is derived according to Euler-Bernoulli beam theory. A method to solve the differential equation under different boundary conditions is proposed based on the segmentation method. The correctness of the method is verified by comparison with the traditional method and experiment, respectively. The dynamic analysis of tensioned ball screw under nonuniform stress in the cutting process is carried out with this method. The influence of the location on the ball screw and amplitude of the axial force produced in the cutting process on natural frequencies of ball screw is researched. Results show that the greater the force, the greater the change in natural frequencies. Furthermore, the change of first two natural frequencies presents a simple harmonic trend with the force moving along the ball screw. Taking a set of cutting force data as an example, the instantaneous frequency of tensioned ball screw in the cutting process is calculated in the end.