Gas shrouded wave improvement

A process of wave soldering a printed circuit board having an under surface, front edge, rear edge and side edges, comprising the steps of:

• projecting at least one solder wave from a solder nozzle above a solder reservoir containing solder, through a slot in a cover means over at least a portion of the solder reservoir;
• providing gas delivery means underneath the cover means to pass shield gas upwards through the slot on both sides of the solder wave and blanket the solder wave;
• conveying the circuit board by conveyor means in a predetermined path above the cover means, the front edge of the circuit board entering the solder wave, the circuit board passing through the solder wave contacting the under surface of the circuit board, the rear edge of the circuit board exiting the solder wave, while the front edge, under surface and rear edge of the circuit board are blanketed by the shield gas, and
• directing shield gas to blanket the side edges of the circuit board passing through the solder wave.

An apparatus for wave soldering an element comprising:

• a solder reservoir adapted to contain molten solder, and having at least one solder wave nozzle projecting therefrom;
• pump means for forming a solder wave from the nozzle;
• cover means for covering at least a portion of the reservoir having at least one longitudinal slot for the solder wave to pass therethrough;
• gas delivery means for supplying gas underneath the cover means, the gas passing upwards through the slot on both sides of the solder wave to provide a gas blanket over the solder wave;
• conveyor means for supporting the element and moving the element in a predetermined path over the cover means ensuring at least a portion of the element passes through the solder wave, and
• end shroud means over each end of the solder wave to direct the gas passing upwards through the slot in the cover means to blanket side edges of the element during the passing of at least a portion of the element through the solder wave.