JPS611467A - Solder coating device - Google Patents

Abstract

PURPOSE:To form uniformly a solder having a substantial thickness on the surface of a circuit board by providing a pair of coating rollers apart from each other in such a manner that the rollers are partly dipped in solder liquid, providing feed rollers right above the coating rollers and providing a solder feed nozzle between the coating rollers. CONSTITUTION:The 1st and 2nd coating rollers 7, 8 are mounted apart at an inter-axis space L in such a manner that the rollers are dipped by about 2/3-3/4 into he solder liquid 2 in a solder tank 1 and the solder liquid feed nozzle 10 is provided between the two rollers 7, 9 relative to a passing line 6. The 1st and 2nd feed rollers 14, 16 with the line 6 in-between are provided right above the rollers 7, 8 and are made vertically finely adjustable by means of adjusting screw devices 15, 17. The roller 14 is preferably made of soft rubber and the roller 16 of hard rubber. A prime moving sprocket 19 is driven in this state to revolve the rollers 7, 8, 14, 16 and the printed board 5 is passed along the line 6 so that the solder liquid 2 is stuck on the pattern surface thereof by the rollers 7,8 and the nozzle 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a solder coating device, and more particularly to a solder coating device capable of coating a patterned surface of a circuit portion of a printed circuit board with solder to a predetermined thickness. .

[Technical background and problems of the invention]

In general, printed wiring boards are made by attaching copper foil to the surface of an insulating board such as Bakelite, and then removing the excess copper foil through an etching process, leaving the circuit area to form the circuit pattern surface. ing. If this patterned surface is left as it is, the surface will oxidize, so normally,
The patterned surface is covered with a solder layer. To apply solder to the patterned surface, conventional equipment uses rollers to transfer molten solder onto the circuit patterned surface of the printed circuit board.

However, when using this type of conventional apparatus, the solder layer could only be applied to a thickness of about 3 microns. Therefore, the solder layer cannot be a sufficient protective film against oxidation of the copper foil, and furthermore, when various electronic components are mounted on the printed circuit board and the lead ends are joined to the circuit part, the solder layer is too thin. Therefore, it was not possible to secure sufficient joint strength. Incidentally, it is desirable that the thickness of the solder layer on the patterned surface of the printed circuit board with this advantage is 5 microns or more, and it has been desired to realize a mounting section for this purpose.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a solder coating device that can uniformly form a sufficiently thick solder layer on a pattern surface that constitutes a circuit part by passing a printed circuit board once along a board passing line. Our goal is to provide the following.

[Summary of the Invention] In order to achieve the above object, a solder applicator according to the present invention includes a solder tank in which a molten solder liquid is stored;
A first application roller disposed so as to be partially immersed in the solder liquid in the solder bath, and the first application roller 40.
- a first feed roller disposed directly above the roller sandwiching the threading line, and a solder bath disposed apart from the first application roller so as to be partially immersed in the solder liquid in the solder bath. a second applicator roller, a first feed roller disposed directly above the first applicator roller with the threading line in between, and an intermediate roller between the first applicator roller and the first applicator roller. It is characterized by a solder supply nozzle that is located at a position that can supply solder liquid toward the threading line.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a spacing coating apparatus according to the present invention will be described below with reference to the drawings.

In the figure, the symbol / indicates a solder tank in which molten solder liquid is stored, and a plurality of heaters, heaters 3, and thermostats are installed at appropriate positions in this solder tank. The temperature is always between 2&θ°C and 270'C.
is maintained within the range. Above the free surface of the upstream solder liquid, a jIn board line B is set for feeding the printed circuit board j from the right to the left in the figure.

A first application roller 7 and a second application roller g are rotatably mounted in the solder tank with a space between their axes. Support shafts 7a are formed protruding from both sides of the first application roller rough, and these support shafts 7a are supported via bearings against the 1011 wall of the solder bath. The second applicator roller is also similar in shape, and its spindle a is supported against the side wall. Further, these application rollers 7 and g are each immersed in the solder liquid 2 at the same height.

A solder supply nozzle A/IO is arranged between the first application roller 7 and the first application roller zone so that the nozzle opening lOa is directed toward the sheet passing line O. .

The lower end of the above supply nozzle IO is the solder supply duct)/
/, and the solder liquid can be introduced inside through the inlet //a of this supply duct)//. A jet fan 1.2 that is rotatably driven by a drive motor (not shown) is installed at the end of the supply duct //, and when the jet fan tit rotates, the jet fan 1.2 rotates from the entrance //PL of the supply duct //. Solder liquid in the solder bath! is sucked into the duct, and is ejected from the nozzle port 10a of the nozzle /θ toward the plate passing direction.

On the other hand, a first feed roller /q is arranged directly above the first application roller 7 with the threading line t in between. This feed roller/4' can be moved slightly up and down by an adjusting screw device/S, thereby making it possible to adjust the roll gap. The roll gap is adjusted according to the Jν of the printed circuit board j, and the printed circuit board j is sandwiched between λ rollers.
Due to the frictional force between them, the sheet is adjusted so that it can be fed in the direction of the arrow along threading line O.

On the other hand, a first feed roller/6 is arranged directly above the first application roller with the threading line 6 in between. This feeding roller 16 can be moved up and down slightly by means of an adjusting screw device/7, thereby making it possible to adjust the roll gap.

Both the seventh feed roller/4' and the second feed roller 16 are made of rubber material, and in this case, the surface hardness of the rollers is such that the first feed roller/l is made of soft rubber. It is advantageous if the first feed roller 16 is made of hard rubber.

Next, the application rollers 7, z, 1. - and the drive system of the feed rollers /ψ and /A will be explained.

A driven Sugerocket ig is fixed on the rotation axis /+a of the first feeding roller /q, while a second feeding roller l
A driving tin rocket /q is fixed on the rotating shaft /Aa of B, and a screw is connected between this driving tin rocket /9 and a driven sprocket /g. Therefore, the rotation axis of the second feed roller lB/A a K
(/IJ) If you connect a geared motor, the chain J
The driven sprocket ig is rotationally driven through. By setting the number of teeth of the driving sprocket /q and the driven sprocket /E to be equal, the circumferential speeds of the first feed roller /da and the second feed roller 16 can be made to match equally.

On the other hand, the rotation of the first application roller 7 and the second application roller g is driven using bin gears. That is, the bin gear 2/
At the same time, two bin gears are provided at the end of the same side of the first power feeding roller ltl, and the two gears are engaged with each other. I cut it,
Similarly, a pin gear 3 is provided at one end of the second applicator roller, and the end of the second feed roller/6 on the same side (
Set the bin gears J and I to engage them. Note that the reference numeral J in the figure indicates a sludge partition plate.

Since the embodiment of the present invention is configured as described above,
After the etching process has been completed, the printed circuit board j whose patterned surface has been coated with 7 lux is fed between the first coating roller 7 and the first feed roller /l along the threading line B. When the printed circuit board j comes out from between them, the molten solder adhering to the circumferential surface of the first application roller 7 is applied to the lower surface of the printed circuit board j. Next, the nozzle port 10 of the solder supply nozzle IO is placed on this solder layer.
The molten solder ejected from a is bathed and further thickened. Next, the printed circuit board j whose patterned surface is coated with the molten solder liquid is fed between the second application roller g' and the second feed roller /A along the board passing line B. Here, the molten solder on the circumferential surface of the second application roller g is applied to the patterned surface of the printed circuit board j, and at the same time, j~10
The thickness of the voice is evened out by μ.

〔Effect of the invention〕

As described above, according to the present invention, the molten solder liquid is applied to the patterned surface of the printed circuit board by the first application roller, and a jet of the solder liquid is applied thereon, so that the solder liquid spreads easily and easily. It is possible to make it thicker. Furthermore, No. The molten solder can be applied with a coating roller and the thickness can be evened out.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view showing an embodiment of a solder coating device according to the present invention. l...Solder hinoki, 2...Solder liquid, 5...Printed circuit board, 6...Threading wire, 7...First applicator roller, ♂...
...Second application roller, IO...Solder supply nozzle,
//... Supply duct, /q... First feed roller, /
S...adjustment screw device, 16/second feed roller, /7
...adjustment screw device, 7g...driven sprocket, /
q...Motive sprocket, 20...Chain.

Claims (1)

[Scope of Claims] 1) A solder bath in which molten solder liquid is stored, a first applicator roller disposed so as to be partially immersed in the solder liquid in the solder bath, and this first applicator roller. A first feed roller is placed directly above the first application roller with the threading line in between, and the first feed roller is spaced apart from the first application roller and is arranged so as to be partially immersed in the solder solution in the solder bath. a second applicator roller that has been applied to A solder coating device comprising: a solder supply nozzle capable of supplying a solder liquid to a threaded wire; 2) The first and second feed rollers are made of rubber, and the surface hardness of the second feed roller is set to a value higher than that of the first feed roller. A coating device according to claim 1. 3) The first and second feed rollers are set to be adjustable in height, and are mounted so that the size of the gap between them and the application roller can be adjusted. The coating device according to item 1.