Vibration Analysis And Structural Optimization Of The Rotating Arc Sensor

In the process of welding, automatic tracking sensor is the key device which decides the accuracy of welding quality. Weld information can be obtained by the changing welding current or welding voltage which is caused by arc sensor. It has many advantages, such as simple structure, strong real-time performance, good stability and so on. In the arc sensor, rotating arc sensor has higher control precision and sensitivity. Therefore, it is widely used in automatic welding equipment. However the mass center of the eccentric block and conductive rod of the rotating part are not on the axis of rotation, exist unbalanced quality. Therefore, when rotating arc sensor rotating, it will produce centrifugal force, causing vibration. Moreovre, its inherent mechanical properties also influence on vibration, brings great influence to welding tracking and welding quality. In order to solve the problem, it is necessary to study the vibration characteristics of rotating arc sensor and its structure is improved.In this article, the virtual prototype model of the rotating arc sensor modeling, kinematics analysis, dynamics analysis, free vibration, forced vibration analysis and structure optimization were done. First, the three-dimensional model of the rotating arc sensor was established by using PROE software. PROE model was import into ADAMS software with the data interface technology, adding material properties, kinematic pair and drive. Kinematics simulation analysis of the multi-rigid-body model was completed and the validity of the model was verified. At the same time, welding torch connection components was simplified, and it was import to the ANSYS software. Finite element model of welding torch connected components was created and the modal neutral file was generated. The modal neutral file was import to replace the original rigid member in ADAMS and the coupled model was set up, provide the model basis for vibration analysis. Then analyze the stress of the bearing and calculate the size and location of unbalanced force, provide the basis for adding incentives when vibration analysis was done. The free vibration and forced vibration analysis of the coupled model was conducted through ADAMS/Vibration, get the system each order natural frequency, modal vibration mode, and the frequency response curve, provides a theoretical basis for the structure improvement of rotating arc sensor. Finally introduces the dynamic balance calculation method of the rotating arc sensor, and calculate the size and location of unbalanced force, so as to determine the installation position of the balance weight. At the same time, the size of the balance weight was optimized by use the parametric design of ADAMS, achieve the goal of the vibration reduction.