摘要 |
The invention relates to a wave soldering device in which solder is pumped up from a solder bath and through a tower and issues therefrom in the form of a wave which engages the underside of a circuit board, flows over a front and/or rear weir of the tower and returns to the solder bath. A conveyor transports circuit boards across the top of the tower and the solder wave. A confining structure is situated adjacent the wave and protrudes into the solder bath. A gas which substantially excludes oxygen is injected from a nozzle and follows a circuitous route bordered by solder in the bath, solder flowing over the rear weir, and walls of the confining structure. The gas exiting from an outflow opening of the confining structure is directed across the solder flowing over the rear weir and onto the downstream line of contact of the solder wave and the board as it leaves the solder wave. Thus, this supply of gas is directed only onto the immediate area where it is most useful, so as to limit dispersal away from this immediate area and minimize the amount of gas required. In a preferred embodiment, secondary means are arranged to supply the gas to other areas of an enclosure for the conveyor and solder tower.
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