Sistema de controle em malha fechada para perfil térmico do processo de refusão SMT

Abstract

The present works presents the development of a plant for a new similar method for the control of SMT (Surface Mounted Technology) reflow process. Therefore, the existing forms of control in the process practiced by the printed circuit board assembly industry were analysed and the results compared with the relation to the simulation environment of the proposed methodology. Considering all the parameters determined in datasheets from leading SMT solder paste component manufacturers, coupled with category-welding requirements defined by the Association Connecting Electronics Industries (IPC), is reasonably concerned, soldering process ensures compliance with requirements, enabling maximum life for assemblies. Through digital controllers, we propose a new approach in an attempt to increase reliability of the temperature control process analised, by the seeking to improve quality, and efficiency of the industrial process. Starting from actual temperature data record of a process on a circuit board assembly with SMT components, it has been modelled or configured on a simulation environment to demonstrate the temperature behavior of the board to the assembled when subjected to the reflow ove. The relationship of the actuator on the motor belt for tracking movement on which the board moves inside the oven to obtain a temperature control method is the key point of the method and allows the inclusion of a new command on the plant, being a speed control linked to the existing temperature control. After demonstration of suitability of environment plant with actual process data, it was possible to incluse a fuzzy driver by changing the open-loop control plant for closed-loop control, and the data detected in the implementation of a controller allow a comparision of the results of this new approach with a current process and demonstrated as the advantages related to the optimization of reflow profiles.