Research On Laser Micro Welding Technology And Process Simulation Of Polymer Diaphragm And Voice Coil

The joining quality of diaphragm and voice coil is one of the key factors affecting the sound quality and service life of the loudspeakers.Aiming at the defects of the traditional adhesive process of diaphragm and voice coil,such as easy aging and low joining strength,a research on laser micro welding technology of diaphragm and voice coil was presented in this paper.The laser was adopted as the heat source to realize the high-quality welding between the polymer diaphragm and voice coil.The combination of experiment and simulation was used to study the technological law and technological process during laser micro-welding polymer diaphragm and voice coil.The structural design of the feeding/positioning/welding process and the numerical simulation of key processes were carried out.The research results in this paper will lay a foundation for the application of laser micro welding technology in the field of diaphragm/voice coil manufacturing.The main workload can be summarized as follows:(1)Based on the surface Gaussian heat source model of laser,the finite element analysis model of laser micro welding polymer diaphragm and voice coil was established by ANSYS.The variation trend of temperature field distribution with clamping force was indirectly characterized by material interface thermal contact conductivity.The effect of different input parameters on the distribution of temperature field and the size of weld formation was discussed systematically.The results of verification experiments showed that the average relative error between the finite element analysis results and the actual results was controlled at about 8%.(2)Based on the simulated data of the finite element analysis model and the actual experiments of laser micro welding process,the initial experimental sampling points were obtained by adopting the optimal Latin hypercube experimental design method.The Kriging prediction model between the input process parameters(laser power,scanning speed and clamping force)and the welding quality(weld width and shear strength)was established.The optimal process parameter change window for laser micro welding was obtained by global optimization of NSGA-II algorithm under the target of minimum weld width and maximum shear strength.And the main effects and contribution rates of each input process parameter on the welding quality were also discussed in detail.(3)The simulation analysis of technological process during laser micro welding of diaphragm and voice coil was carried out.The functions and characteristics of the feeding / positioning / laser micro welding / unloading process were analyzed.The static and buckling analysis of diaphragm during the feeding process were carried out by ANSYS/Workbench.The ADAMS kinematics simulation was used to verify the coordination and reliability of the virtual assembly model of the diaphragm feeding mechanism.