Design and Application of The Painting Material Supply System of The Painting Robot for Steel Products

With the increase of painting works and the decrease of skilled workers, the demand for robot painting of the large-scale steel product is rapidly increasing. But there are many technical problems in the development of the painting robot for this use. The collision between a robot and a work-piece is one of the most important problems, because the robot operates in a small space of a work-piece. Above all, the collision of the painting material supply hose with painted film on a work-piece is very serious. To avoid the hose collision, we propose an in-line type of paint supply mechanism using swivel joints. The key point in this system is the sealing performance and its durability, and we propose the piping system with compliance to strengthen the sealing performance. In this paper, the design method of this system is discussed on the basis of the analysis of the fluctuatinal elastic deformation of a O-ring in the swivel joint. We produced a prototype of the painting robot with the in-line system designed by this method. Application of this robot to the painting of ship-hull block is also discussed. Results from this application show the effectiveness of the in-line system.