A Parametric Distribution Model of Electrostatic Spray Rotating Bell and Application for Automobile Painting

Compared with spray gun spraying, electrostatic spray rotating bell (ESRB) spraying can provide better film forming quality and higher adhesion rate, which is more suitable for the automobile painting. However, the complexity of the automobile surface geometry and the spray pattern produced by ESRB painting makes the trajectory planning and the determination of spraying parameters challenging. This research presents a coating thickness distribution model for ESRB atomizer with uniform motion and establishes a parametric model to express the functional relationship between the thickness distribution model and atomizer parameters. The proposed parametric model aims to provide a guideline for the determination of spraying parameters in the process of off-line programming in the painting industry. Firstly, a novel feature points fitting distribution model was established based on the characteristics of ESRB uniform linear spraying coating. The model can fully visualize the cumulative profile characteristics of coatings. Secondly, the orthogonal experiment, multilevel and multifactor, was designed to analyze the variation of feature points with the painting parameters. Then, based on the requirements of the spraying process, an objective function is established for the coating thickness and other indicators of each area, and a genetic algorithm is used to solve it, so as to determine the ESRB spraying parameters. Finally, three simulation experiments show that the new model is effective and has high prediction accuracy, which can be effectively applied to the ESRB spraying system.