METHOD AND APPARATUS FOR FLUXING AND SOLDERING TERMINALS ON A PRINTED CIRCUIT BOARD

摘要

Fluxing and soldering terminals on a printed circuit board by an in-line process in which flux concentration is determined at specific locations laterally of the passline. At each of the positions infrared light is passed through a wall of flux which is being directed at the board. The infrared light becomes partly absorbed by materials in the flux and the unabsorbed light which passes through the wall of flux is used to generate signals corresponding to the different wavelengths of unabsorbed light at each of the locations. This enables a determination to be made of the flux concentration at each location. The signals are preferably used to effect a change in the flow rate of flux at any specific location so as to control the amount of flux deposited upon the board. Particularly useful for "no-clean" flux applications.