Patent ID: 6168064
Filing Date: 2001-01-02
Classification: B23K,F27B,H05K

Abstract:
Apparatus for controlling solder reflow time and temperature of a component populated substrate, comprising: a multi-zone reflow oven having a substrate carrier belt, heating elements means and convection fans, belt drive means for controlling the carrier belt speed, fan drive means for controlling the convection air flow, power means for controlling the temperature of said heating element means, said reflow oven having a central controller capable of effecting control of said belt drive means, said fan drive means, and said power means, keyboard means coupled to said central controller for setting initial control parameters in said central controller and for creating a desired solder paste temperature profile and deviation set points in each of the zones of said multi-zone reflow oven, thermal scanner means coupled to said central controller for thermally scanning a substrate moving through said reflow oven, said thermal scanner means comprising an infra red optical device for generating an infra red thermal map of a view of said substrate, said central controller having means for determining the actual solder paste temperature at points on said solder paste temperature profile, by analysis of said infra red thermal map, and program control means in said central controller for generating feedback control signals for changing one or more of said belt drive means, said fan drive means and/or said power means to effect a desired solder paste temperature at said points scanned by said thermal scanner.