Shield gas wave soldering
AssigneeElectrovert Ltd.
InventorsCarlos A. Deambrosio, John Gileta
Life of this patent
Estimating the term…
Abstract
A wave soldering apparatus and process occurs in an atomsphere which substantially excludes oxygen. By providing a gas blanket over the solder, reduction in dross occurs and improved soldering results avoiding the necessity of removing flux residues. Gas diffusers are provided on both sides of a solder wave in an enclosure, the diffusers are placed below the path of the element to be soldered and a further gas diffuser is positioned above the element to be soldered. The gas diffusers supply a calm gas blanket over the solder wave so no turbulent movement of gas occurs within the enclosure.
Claims38
Process for wave soldering an element comprising the steps of
- preheating the element in a shield gas atmosphere substantially excluding oxygen;
- moving the element in a predetermined path;
- forming a solder wave beneath the path so that at least a portion of the element passes through the solder wave while maintaining liquid solder surfaces exposed to the shield gas;
- producing an oscillation in the solder wave during passage of the element therethrough, the frequency of oscillations being in the range of about 20 to 400 Hertz, and
- maintaining the element in the shield gas atmosphere until solder on the element has solidified.
Process for wave soldering an element comprising the steps of:
- moving the element in a predetermined path through a shield gas atmosphere substantially excluding oxygen,
- forming a solder wave beneath the path so that at least a portion of the element passes through the solder wave, and
- supplying shield gas through at least one first diffuser on one side of the solder wave positioned below the path, through at least one second diffuser on the other side of the solder wave positioned below the path, and through at least one third diffuser over the solder wave positioned above the path, such that shield gas blankets the solder wave and surrounds the element passing therethrough.
An apparatus for wave soldering an element comprising,
- an enclosure for a shield gas atmosphere substantially excluding oxygen the enclosure having an entry and an exit;
- means for forming at least one solder wave in the enclosure above a solder reservoir,
- means for conveying the element in a predetermined path through the enclosure from the entry to the exit, the path ensuring at least a portion of the element passes through the solder wave from one side to the other side, and
- at least one first shield gas diffuser in the enclosure positioned on the one side of the solder wave below the predetermined path, at least one second shield gas diffuser in the enclosure positioned on the other side of the solder wave below the predetermined path, and at least one third shield gas diffuser in the enclosure positioned over the solder wave above the predetermined path, the shield gas diffusers providing a shield gas blanket within the enclosure for the solder wave and solder reservoir and the element passing through the solder wave.
An apparatus for wave soldering an element comprising:
- means for conveying the element in a predetermined path through a shield gas atmosphere substantially excluding oxygen,
- means for forming a solder wave above a solder reservoir, the predetermined path positioned so that at least a portion of the element passes through the solder wave from one side to the other side, and
- at least one first shield gas diffuser positioned on the one side of the solder wave below the predetermined path, at least one second shield gas diffuser positioned on the other side of the solder wave below the predetermined path and at least one third shield gas diffuser positioned over the solder wave above the predetermined path, the shield gas diffusers providing a shield gas blanket for the solder wave, the solder reservoir and the element passing through the solder wave.
Process for wave soldering an element comprising the steps of:
- preheating the element in a shield gas atmosphere substantially excluding oxygen,
- moving the element in a predetermined path;
- forming at least one solder wave beneath the path so that at least a portion of the element passes through the solder wave while maintaining liquid solder surfaces exposed to the shield gas;
- providing a pressurized effect on the element using a moving device within the solder wave during passage of the element therethrough, and
- maintaining the element in the shield gas atmosphere until solder on the element has solidified.
A process for wave soldering printed circuit boards comprising the steps of:
- preheating the circuit boards;
- moving the circuit boards in a predetermined path through a shield gas atmosphere substantially excluding oxygen
- forming a solder wave within the shield gas atmosphere beneath the path so that at least a portion of the circuit boards pass through the solder wave;
- and
- supplying the shield gas from at least one first gas elongated diffuser extending on one side of the solder wave positioned below the path, from at least one second gas elongated diffuser extending on the other side of the solder wave positioned below the path, and from at least one third gas elongated diffuser extending above the solder wave positioned avove the path to blanket the solder wave and the circuit boards passing therethrough.
An enclosure for installation over a solder reservoir having means therein for forming a solder wave, the enclosure for containing a shield gas atmosphere substantially excluding oxygen, the enclosure adapted to enclose not more than the solder reservoir and having and entry and an exit for a path of travel for circuit boards therethrough, sealing means on the enclosure to maintain the shield gas atmosphere in the enclosure, and gas distribution means for admitting shield gas into the enclosure comprising a first shield gas distributor for location in the enclosure in a position on one side of the solder wave below the path of travel, a second shield gas distributor for location in the enclosure in a position on the other side of the solder wave below the path of travel, and a third gas distributor for location in the enclosure in a position above the solder wave above the path of travel.
The process for wave soldering printed circuit boards comprising the steps of:
- preheating the circuit boards;
- moving the circuit boards in a predetermined path through an enclosure containing a shield gas atmosphere substantially excluding oxygen;
- forming a solder wave above the solder reservoir within the shield gas atmosphere in the enclosure and beneath the path so that at least a portion of the circuit boards pass through the solder wave and the enclosure enclosing not more than the solder reservoir;
- and
- blanketing the solder wave and the circuit boards passing therethrough with shield gas supplied within the enclosure by a first gas distributor on one side of the solder wave positioned below the path, and by a third gas distributor above the solder wave positioned above the path.
Dependencies are inferred from the claim text.