Soltec B.v.

Rolf A Den Dopper

Jeroen Lambertus Schmits

Franciscus Johannes De Klein

Johannes J Luijten

The invention relates to an oven for reflow soldering objects such as printed circuit boards. A temperature differential is established between the top and bottom surfaces of the board to allow gases liberated from solder paste within through-holes to escape, thereby preventing the formation of voids. The oven provides a flow of gas at a first temperature from an upper gas supplying means to the top side of the board. A flow of gas at a second temperature is directed at the bottom side of the board by a lower gas supplying means. According to one aspect of the invention, a portion of the gas supplied by the upper gas supplying means is captured by the lower gas supply means and is heated or cooled to the second temperature. According to another aspect of the invention, a number of pairs of independantly controllable upper and lower gas supplying means are arranged along a conveyor to provide a temperature profile to perform reflow soldering.

Reflow oven

Reflow soldering apparatus with a rotative configuration

A reflow soldering apparatus includes a plurality of heating compartments connected in series for heating objects for soldering; transporting means for successively carrying the objects through the compartments; and at least first and second cooling compartments connected subsequent to the heating compartments for cooling the soldered objects. The first cooling compartment subjects the objects to a first, descending temperature gradient, and the second cooling compartment subjects the objects to a second, descending temperature gradient, wherein the second temperature gradient is steeper than the first temperature gradient. The objects are cooled in the first cooling chamber to a temperature below the solidification temperature of the solder.

Reflow soldering apparatus with improved cooling

The invention relates to a soldering apparatus comprising: a soldering chamber; transporting means for transporting the objects to be soldered through the soldering chamber; and heating means for heating the objects to be soldered in the soldering chamber, wherein the heating means are formed by means for feeding heated gas to the chamber. A simple device is thus obtained which heats uniformly. Such an apparatus can be embodied in both closed and open form. According to one of the preferred embodiments the means for feeding heated gas are formed by at least one heating unit, wherein the heating units are each formed by a fan and at least one heating device, for instance an electrical heating filament, connected forwardly thereof. Cooling units can also be used.

Reflow soldering apparatus

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.

Growing community of inventors

Roosendaal, Netherlands

Rolf A Den Dopper