| 摘要 |
In soldering devices such as printed circuit boards it may be desirable to expose only those portions of the board having terminals to be soldered to the molten solder. To this end an inert atmosphere spot soldering process and apparatus uses pockets arranged to match the arrangement of the terminals to be soldered. The cups are filled to overflowing with liquid solder and provided with an enveloping flow of hot inert gas. The terminals and their surrounding area are exposed to the hot inert gas for a period sufficient to drive off substantially all volatile liquids and the terminals are then immersed in the solder to a depth determined by the meniscus of the liquid solder in the pockets without permitting the board to contact the pockets. After immersion, the terminals are raised gently, non-parallel to the solder surface, until they are above the solder and then the flow of inert gas is terminated permitting the solder to solidify. The inert gas may be heated by thermal conduction from the liquid solder.
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