Automated rework of printed circuit board assemblies: Methods and procedures

Abstract

In the last few years, although the number of rework stations available on the market has grown considerably, the process of repair has not been fully automated due to the requirement for flexibility and because most processes are complex, unlike printed circuit board assembly (PCBA), which is concerned with dedicated processes. In order to automatically handle a variety of PCBs each of which may have different fault problems, an autonomous rework system capable of advanced sensing, in-process inspection and automatic planning is required. This paper presents automated rework methods and procedures which were developed to extend the capability of a robotic assembly cell so that it could perform rework and in-process inspection of single-sided PCBAs for a minimum batch size of one. It outlines detailed rework procedures for surface mount (SM) and through hole (TH) components, summarizes the hardware requirements and the structure of the cell and evaluates the procedures developed with regard to rework effectiveness.