HU219835B - Method and apparatus for eliminating varnish remnants on the soldered surface for dipped soldering - Google Patents

Abstract

The subject of the invention is a method and equipment for eliminating shape residues on the soldered surface during immersion soldering. The equipment used for the immersion soldering of lacquered copper wires to the contact pins (7) of electrical components contains a vertically movable immersion body (9), which dips into the solder tank (3) connected to the immersion vessel (5) via pipes (4) and overflows the solder (2) in the immersion vessel (5). When the immersion body (9) is immersed, the contact pins (7) are still immersed, so that the varnish residues on the surface of the solder (2) in the solder immersion vessel (5) are washed away. ŕ

Description

The present invention relates to a method and apparatus for eliminating lacquer residues on a soldered surface during immersion soldering. Soldered copper wires are soldered to the contact pins of electrical building blocks in an automatic immersion device by applying a soldered dip from the solder bath to the contact pins.

For the production of induction chokes or other electrical building elements, tinned copper wires are generally used as winding wires. These lacquered copper wires are connected to the contact pins of the choke coils or other building elements (printed circuit boards to the contact pins) by wrapping the coil wire several times around the pin and then immersing the pin in a tin bath.

Doing so may cause residual lacquer on the winding wire to be deposited on the contact pins, thereby adversely affecting the solderability of the contact pins on the printed circuit boards.

For example, these residues are removed mechanically. However, this is complicated and does not preclude, for example, faulty short-circuiting and winding wire damage.

The formation of lacquer residues on the contact pins is substantially avoided by locally displaced dipping and lifting of the contact pins. However, this process cannot be accomplished at reasonable expense in some commonly used automatic submersible soldering equipment in which a soldered dip is led upward from the solder bath to the contact pins.

DE-OS 25 14 284 describes a process in which flux vapors are aspirated and the solder is continuously refilled. The lacquer residue is not removed from the solder and must be removed afterwards.

It is therefore an object of the present invention to provide a method and apparatus for eliminating paint residues on a soldered surface when using the outlined submersible soldering apparatus.

According to the invention, this object is solved by overflowing the solder in the brazing vessel after the soldering is complete, while the contact pins are still submerged.

According to the present invention, the object of the invention is to provide a vertically movable submersible body which, when immersed in a soldering vessel connected to the soldering vessel by tubes, overflows the solder in the soldering vessel.

In a particularly preferred embodiment, the dive body is heated.

The invention will be further described with reference to an exemplary embodiment, wherein:

Figure 1 is a schematic diagram of an apparatus according to the invention.

Fig. 1 shows a stationary heated solder bath 1 containing liquid solder 2. The soldering vessel 3 is movable up and down in the direction of the arrow and the soldering vessels 5 connected thereto by tubes 4 are used to draw solder 2 from the soldering bath 1.

An electrical building element 6, such as a choke coil, has contact pins 7 on which the coil wire 8 is secured by winding it around the contact pins. In order to solder the coil wire 8 onto the pins 7, the building element 6 is submerged in the solder 2 in the soldering pot 5.

After soldering is completed, but when the pins 7 are still submerged, the solder 2 in the soldering vessel 5 is overflowed by immersing a dip body 9 in the soldering tank 3. As a result, the solder 2 in the brazing vessel 5 is ejected and overflowed.

With this solution, residual lacquer floating on the surface of the solder 2 is rinsed off and these pins 7 cannot subsequently remain on the pins 7 when they are subsequently removed.

The immersion body 9 is preferably of heated design so that the solder 2 is not cooled during immersion.

Preferably, a heated immersion body 9 is used which is non-wettable and non-oxidizable by the solder 2 and has a temperature greater than that of the solder bath 1.

It is also possible to cause two time-shifted overflows of solder 2 by immersing the dip body 9 in two steps. The first wave of solder is created just before the start of the soldering process to obtain a clean, lacquer-free solder. In this case, the lacquer 2 from the solder bath 1, which has already been contaminated with lacquer during previous soldering operations, is returned to the solder bath 1 together with the overflow solder 2. The second solder wave is created as described above before soldering is complete. In this case, the lacquer residue on the surface of the soldering material 2 during the current soldering process also slides off with the overflow soldering material 2, thereby preventing the lacquer residue from sticking to the contact pins 7.

Claims (6)

PATENT CLAIMS A method for eliminating lacquer residues during brazing by soldering copper lacquer wires to the contact pins of electrical components, in which the brazing is carried out in an automatic immersion device by brazing ), after soldering is completed, the soldering material (2) is overflowed after the soldering pins (7) have been submerged. Method according to claim 1, characterized in that the solder material (2) is overflowed in the soldering vessel (5) before the soldering process begins. An apparatus for carrying out a process according to claim 1 or 2, comprising a soldering bath and a photo-immersion vessel which can be immersed in and removed from the soldering bath, characterized in that it comprises: A vertically movable submerged body (9) immersed in a soldering vessel (3) connected to the soldering vessel (5) via tubes (4) and thereby overflowing the soldering vessel (2) in the soldering vessel (5). Apparatus according to claim 3, characterized in that the immersion body (9) is heated. Apparatus according to claim 4, characterized in that the submerged body (9) is not wettable or oxidizable by the solder (2). Apparatus according to claim 4 or 5, characterized in that the temperature of the immersion body (9) exceeds the bath temperature of the solder (2).