Wafer-400 Cnc Chip Carving Machine Dynamic Characteristics Analysis With The Screw Test System Development,

The function of transmission system in NC (numerical control) machine tools is transferring movement and power from power source to the implementation pieces of machine tools, and ensuring that there is a good dynamic character in transferring process. The transmission system often got affected from exciting force and impact torque when it is running. This may bring the axis component bending and torsion vibration, and influencing the processing performance of machine tools. With the modern development of machine tool, the requirement for mechanical structure performance of transmission system has been higher. Thus, it will be a very important practical significance to research the dynamic character of NC machine tool feeding transmission system.This paper came from a wafer carving machine tool development of a certain Automation Co., Ltd. Guangdong Province. In this paper, the finite element analysis method is introduced to establish the dynamic modeling of whole machine tool and worktable feeding transmission system. Dynamical characters of feeding transmission system are analyzed. The machine tool vibration test system was designed. The finite model was verified through testing dynamic parameters of the machine tool. Ball screw is a key part of machine tool and determines the machining precision of machine tool greatly. According to this, we develop the measure instrument for friction moment of ball screw. The paper probed deeply into the influence of ball screw vibration characteristics to dynamic performance of machine tools.Main achievements and features in the paper are as follows:1,The elasticity system dynamics equation of finite element technology is introduced. The discrete dynamical model of Numerical Control Machine Tools is established. In accordance with the forces, a kind of single freedom degree dynamics model about worktable feeding transmission system is developed in considering the damping.2,In finite element analysis software ANSYS, the dynamic character of machine tool key parts is analyzed. Taking into account the mechanical joints and the spring-damper units is used to simulate the dynamical characters of joints, the finite element model of worktable feeding transmission system and whole machine tool were established. Then the modal analyses were preceded. So the natural frequencies and vibration shape were obtained. In addition, the humorous analysis of worktable feeding transmission system was preceded to calculate the dynamic response of the displacement. 3,Set up the vibration test system of NC machine tool. The dynamic parameters of machine tools were identified through dynamic testing on various working conditions. By comparing the results of finite element analysis and the experiment, they matched well in the scope of error, so the correctness of finite element model was proved and got a satisfying result. Use different ball screws in worktable feeding transmission system. Study the influence pf ball screws' vibration character on machine tool dynamic performance.4,Analyze the ball screw mechanism of ball screw unit. Study the impact of ball incentives and calculate the impact frequency of ball on reverse instrument. Designed and developed the ball screw friction moment measure instrument. The wavelet transform technology is introduced in signal processing. Research shown that the friction's changing was one of the main factors for friction moment fluctuation when screw balls came into the raceway. The mean value of friction moment and the screw speed was approximate proportional relationship.