JPH0719658Y2 - Jet type automatic soldering equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to a jet type automatic soldering device for a printed circuit board, and in particular, a first nozzle and a second nozzle are mounted on a printed circuit board mounted in high density. The present invention relates to a jet-type automatic soldering device capable of forming two types of jet waves from the first nozzle and performing highly accurate soldering processing when performing soldering with a jet of molten solder.

"Conventional technology" In recent years, due to advances in IC technology,
As shown in FIG. 6 and FIG. 6, the mounting density has become higher, and electronic components have been mounted at extremely narrow intervals, and a chip having no lead wire on one printed circuit board 5 is mounted. In many cases, both the component 16 and the discrete component 15 with a lead wire are mixed and mounted. Under such circumstances, the first nozzle and the second nozzle are provided in the solder bath, and the printed wiring board on which the electronic components to be transported on the solder bath are mounted is first soldered by the first nozzle. In the automatic soldering device that removes the dripping of the solder in the shape of a stagger at the second nozzle,
7 and 8 show the injection holes for the molten solder in the nozzle of
There is one that is formed to have a shape as shown in FIGS. 10, 10 and 12 to improve the efficiency of the soldering process.

[Problems to be solved by the invention] However, first, the jet holes 1 shown in FIG. 7 are arranged in the nozzle plate 2 in a grid pattern along the transfer direction of the printed circuit board as shown by the arrow in FIG. Therefore, the molten solder from the jet holes 1 is not jetted over the entire surface of the printed circuit board,
Since there is no jet flow between the jet holes 1, there is a problem that the solderable flow area of the printed circuit board is limited.

On the other hand, the jet holes 3 in FIG. 8 are provided by arranging slit-like nozzle holes on the nozzle plate 4 in a staggered manner.
It seems that molten solder can be jetted over the entire area of the printed circuit board when the printed circuit board 5 is transferred in the direction of the arrow for soldering, but as shown in FIG. Since the area of the jet hole 3 is several times wider, the jet height of the molten solder from the jet hole 3 becomes lower by the increase of the area (h ₁ > h ₂ ). Moreover, as shown in FIG. 9, in order to remove the so-called flicker-like solder that drastically drops when the molten solder is attached by the first nozzle by the jet flow of the molten solder from the second nozzle, as shown in FIG. 5 is transferred with an inclination angle. Therefore, in combination with the fact that the jet height of the molten solder from the jet holes 3 is lower than the jet height of FIG. 7 as described above, the printed circuit board 5 is inclined and transferred. Even if the molten solder from the jet holes 3 adheres to the printed circuit board 5, even if the second row has the same jet height as the first row, the second row jet holes 3
There is a possibility that a situation may occur in which the molten solder from the inside does not adhere.

The jet hole 6 in FIG. 10 is a nozzle plate 7 in which a large number of small holes 6a are arranged in a line and a long hole 6b is provided behind the small holes 6a.
The printed wiring board 5 is soldered from the small holes 6a in the front row with a jet of molten solder having a high height, and the jetted molten solder from the slots 6b smooths the soldered portion. As in the case shown in FIG. 7, since there is no jet of molten solder between the small holes 6a in the front row, it is not possible to solder the entire area of the printed circuit board 8 evenly, and the long holes 6b in the rear row melt. In the solder jet, as shown in Figs. 10 and 11,
Since the jet height is low (h ₃ > h ₄ ) and the printed circuit board 5 is inclined and transferred, it may not be possible to deposit molten solder to supplement the unprocessed portion between the small holes 6a.

The jet hole 9 in FIG. 12 has a small hole 9a in the front row of the nozzle plate 10 and a large hole 9b in the rear of the small hole 9a. Therefore, the jet hole 9 is similar to the jet hole 1 in FIG. The small holes 9a and the large holes 9b are aligned in a grid pattern, and the jet height is low (h ₅ > h ₆ ) as in the case of the long holes 6b in FIG. 10 (FIGS. 12 and 13). Therefore, the same problems as those in FIGS. 7 and 10 occur, and it is not suitable for the soldering process with high accuracy and evenness on the printed circuit board 5 mounted with high density.

Further, as shown in FIG. 14, as the jet holes 11 of the first nozzle, there are some nozzle plates 12 in which several long slots 11a are provided in a row, but as shown in FIG. Since the soldering process is carried out while having θ, the jetted molten solder is less likely to come into contact with the printed circuit board 5 in the rear slot side long groove holes 11a, and thus the number of the long groove holes 11a is limited. . Therefore, as shown in FIG. 16, the nozzle hole 14a of the first nozzle 14 has the same shape as the second nozzle and has a width S.
It is also conceivable to make the height of the molten solder of the first nozzle 14 higher than that of the second nozzle (large jet energy density) as shown in FIG.
Simply by increasing the jet height of the molten solder, good processing can be performed when the lead wire of the discrete component 15 is soldered to the through hole 17 as shown in FIG.
As shown in FIG. 19, in a chip component (or flat type component) 16 with a lead wire, since the exterior is made of synthetic resin, the jet solder has a space 18 in the part of the lead wire to be soldered by the surface tension of the exterior. As a result, vaporized gas such as flux solvent accumulates in the space 18 to form a larger space, resulting in a defective portion that is not soldered.

Therefore, in view of the above circumstances, the present invention combines a jet wave that has high jet density energy and spreads so as to blow even on the corners of parts, and a jet wave that solders electronic parts so that they slide, It is an object of the present invention to provide a jet-type automatic soldering device capable of soldering a printed circuit board mounted in high density with high accuracy and reliability.

"Means and Actions for Solving the Problems" The present invention has been made to achieve the above object, and has a pressurizing means for pressurizing the molten solder contained in the solder bath.
Moreover, in the solder bath, a first nozzle that forms a plurality of rows of solder jet waves and a single solder jet wave are formed in the direction in which the printed circuit board on which the electronic component is mounted is transported on the solder bath. In a jet-type automatic soldering device provided with a second nozzle, the first nozzle jets a plurality of rows of molten solder in the transfer direction of the printed circuit board, and the jets of each row are discharged from the narrow groove holes. A molten solder with a high jet density energy and a high jet height is jetted, and molten solder with a height lower than that of a large-diameter hole that is provided at appropriate places in the narrow slot and with a narrow slot is used. The jet height is made to appear alternately in a zigzag manner for each row, and in the case of the molten solder jet with high jet density energy, there is a narrow space due to the presence of lead wires of electronic components on the printed circuit board. Melted solder is pressed to Inclusive filled, and in other places to be soldered of the printed circuit board, in which the jet low melt solder height is such that the soldering process in the Namerameru so.

[Embodiment] An embodiment of a jet type automatic soldering device according to the present invention will be described below with reference to the drawings.

First, referring to the first embodiment shown in FIGS. 1 and 2, reference numeral 21 is a solder bath. The solder bath 21 has a heater 22
The solder 23 to be melted in is stored. A fin 24 as a pressurizing means driven by a motor is arranged in the solder bath 21. The fins 24 circulate the molten solder 23, and each jet hole of the first nozzle 25 and the second nozzle 26.
The molten solder 23 is jetted from 34 and 32. As in the conventional case, the printed circuit board 29 is adapted to be transferred while being inclined by α on the solder bath 21 with various electronic components 30 of chip type or discrete type mounted. The first nozzle 25 is formed as shown in FIG. 2 described later. The second nozzle 26 is similar to the conventional one, and has a jet hole 32 having a long hole in the top wall of the nozzle 31 having a trapezoidal cross section. In the first nozzle 25, jet holes 34 as shown in FIG. 2 are formed on the top wall of the nozzle plate 33 in three rows in the transfer direction of the printed circuit board 29. Each jet hole 34 has a narrow groove 35 having a preset width and a large diameter hole 36 having a diameter larger than the width of the narrow groove 35 in the longitudinal direction of the narrow groove 35 on the same straight line. It is formed at the position. The positions of the large-diameter holes 36 in each row are arranged so as to be staggered so that they do not overlap with each other in the transfer direction of the printed circuit board 29 shown by an arrow in FIG.

Therefore, in the first nozzle 25, as shown in FIG.
The jet waveforms of the molten solder 23 jetted from the jet holes 34a in the second row, the jet holes 34b in the second row, and the jet holes 34c in the third row are:
It has a jet waveform in which the jet flow from the narrow groove 35 is high and the jet flow from the large diameter hole 36 is low. In other words, the molten solder 23 pressed by the fins 24 is narrowed down by the narrow groove 35, the jet height becomes high, and the jet density energy becomes large.
On the other hand, since the hole area of the large diameter hole 36 is larger than that of the narrow groove hole 35, it does not have the effect of narrowing down the jet flow of the molten solder like the narrow groove hole 35, and therefore the jet height is low and the jet density energy is small. Moreover, since the large-diameter holes 36 are alternately arranged in each row and are arranged in a zigzag pattern when observed as a whole, the low jet wave L of the molten solder 23 is directed to the transfer direction of the printed board 29. Alternately, the high jet waves H also appear alternately as a result of the narrow slots 35 being arranged in a staggered manner. Therefore, if attention is paid only to a certain portion of the printed board 29, as the printed board 29 is transferred on the solder bath 21, first, in the jet holes 34a of the first row, the jet height from the narrow groove 35 is high, that is, the jet flow. If the soldering process is performed by the molten solder 23 having a large density energy, the jet density energy of the molten solder 23 is large, so that the lead wire of the electronic component 30 is present and the space to be soldered is extremely narrow. Even at the location, the molten solder 23 is pushed into the location for soldering. Next, the above-mentioned portion of the printed circuit board 29 is
It is located above the large diameter hole 36 of the jet hole 34b in the second row, and is soldered in such a state that it can be slid with the molten solder 23 with a small jet density energy from the large diameter hole 36. Perform soldering process extensively and cleanly. Further, the above-mentioned portion of the printed board 29 is again soldered with the molten solder 23 having a large jet flow density energy from the narrow groove 35. In this case also, the blowing force of the molten solder 23,
The molten solder 23 is pushed into a narrow place for soldering. On the other hand, the other part of the printed board 29 is soldered with the molten solder 23 having a low jet height from the large diameter hole 36, that is, a jet flow hole 34a of the first row, that is, a small jet density energy, and the second row. In the jet hole 34b of the jet groove 34b, the molten solder 23 having a high jet height from the narrow groove 35, that is, a large jet density energy, is soldered, and the jet density energy from the large diameter hole 36 is again fed in the jet hole 34c in the third row. There is also a portion to be soldered with the small molten solder 23. In this case as well, in the same manner as above, the molten solder 23 with a small jet density energy from the large-diameter hole 36 is subjected to a smooth soldering process so that the printed board 29 can be slid smoothly, and the narrow groove 35
From the molten solder 23 with a large jet density energy from
The molten solder 23 is pushed into a narrow space due to the presence of a lead wire or the like to perform a soldering process. Next, the printed circuit board 29 is transferred from the first nozzle 25 onto the second nozzle 26, and removes the so-called flicker-like unnecessary solder generated during the soldering process by the first nozzle 25.

FIG. 3 shows the second embodiment, and in order to form the narrow groove 35 and the large diameter hole 36 in the jet holes 34a to 34c of the first to third rows of the first embodiment, 4 The nozzle plate pieces 37a to 37d are used. That is, a plurality of recessed portions 38a are cut out at regular intervals at the rear edge of the front nozzle plate piece 37a. The front end edge and the rear end edge of the two middle nozzle plate pieces 37b, 37c are notched with recessed portions 38b-38e at regular intervals so that their positions are staggered (staggered). The front end edge of the nozzle plate piece 37d at the rearmost portion is also provided with recessed portions 38f at regular intervals. Then, the four nozzle plate pieces 37a to 37d are sequentially arranged at appropriate intervals in the transfer direction of the printed circuit board 29 shown by the arrow in FIG. 3, but at this time, the concave portions of the nozzle plate pieces 37a to 37d are notched. The concave portions 38a to 38f are formed in a zigzag pattern so that the portions 38a to 38f face each other and also face each other with respect to the transfer direction of the printed circuit board 29. Nozzle plate pieces 37a-37d
The gap length between the nozzle plate pieces 37a to 37d can be adjusted so that they can be adjusted according to various conditions to be soldered. The recessed portions 38 facing each other have the same function as the large-diameter hole 36 in the first embodiment, and the gaps between the nozzle plate pieces 37a to 37d at other locations are the same as those in the first embodiment.
It has the same function as the narrow slot 35 of the embodiment. Others are the same as those in the first embodiment.

FIG. 4 shows the third embodiment, and three nozzle plate pieces 39a-3
Using 9c, the recessed portions 40a to 40c are cut out at regular intervals at the rear end edges of the nozzle plate pieces 39a to 39c. Also in this case, each of the nozzle plate pieces 39a to 39c has a printed circuit board 29 indicated by an arrow in FIG.
Of the nozzle plate pieces 39a to 39c are staggered with respect to the transfer direction of the printed circuit board 29 at this time. To be formed. Then, the recessed portions 40a to 40c and the front end edges of the nozzle plate pieces 39a to 39c facing the recessed portions 40a to 40c perform the same function as the large diameter portion 36 of the first embodiment,
Further, in the other gaps between the nozzle plate pieces 39a to 39c,
It has the same function as the narrow slot 35 of the embodiment. Regarding the nozzle plate piece 39c at the last part, each nozzle plate piece 39a to 39c
The narrow groove 35 and the large diameter hole 36 as in the first embodiment are formed between the frame 41 and the frame 41. The gap between the nozzle plate pieces 39a to 39c can be adjusted so that the nozzle plate pieces 39a to 39c can be moved according to various conditions to be soldered. Others are the same as those in the first embodiment.

"Effect of device" According to the jet type automatic soldering device of the present invention,
The nozzle of (1) forms a jet hole of the molten solder with a combination of a small groove hole and a large diameter hole arranged at a constant interval, and the jet hole is provided in a plurality of rows in the transfer direction of the printed circuit board. Every time, the soldering process is performed on each part of the printed circuit board using the jet wave of molten solder with a large jet density energy from the narrow slot and the jet wave of molten solder with a small jet density energy from the large diameter hole. In the jet wave of molten solder with a large jet density energy, even if there is a very narrow space to be soldered due to the presence of lead wires, etc., the molten solder is pushed into the place and the soldering process is performed, In addition to this type of soldering process, the jet wave of molten solder, which has a small jet density energy, makes smooth and wide contact by slidingly touching the printed circuit board to be soldered. Since repeats the processes of soldering, even higher printed circuit board of recent packaging density, it is extremely convenient to obtain performs processing and reliably soldered with high accuracy.

[Brief description of drawings]

FIG. 1 is the first of the jet type automatic soldering device according to the present invention.
FIG. 2 is an explanatory view showing the entire structure of an embodiment, FIG. 2 is an explanatory view showing a plane structure of a first nozzle and a jet waveform of molten solder in the first embodiment, and FIG. 3 is a first nozzle showing a second embodiment. FIG. 4 is a plan view of a main part of a first nozzle showing a third embodiment, FIG. 5 is a cross-sectional view of a main part showing a mounted state of a printed circuit board which is currently used, and FIG. 5 is a plan view of an essential part of FIG. 5, FIG. 7 is an explanatory view showing a plane configuration of a conventional first nozzle and a jet waveform of molten solder, and FIG. 8 is a plane configuration of another conventional first nozzle. Explanatory diagram showing jet waveform of molten solder, FIG. 9 is an explanatory diagram showing a soldering state to the printed circuit board by the first nozzle of FIG. 8, and FIG. 10 is a plan configuration of another conventional first nozzle. And an explanatory diagram showing the jet waveform of molten solder, and FIG. 11 is a soldering state on the printed circuit board by the first nozzle of FIG. FIG. 12 is an explanatory view showing a plane structure of another conventional first nozzle and a jet waveform of molten solder, and FIG. 13 is soldering to a printed circuit board by the first nozzle of FIG. FIG. 14 is a plan view showing a planar configuration of another conventional first nozzle, and FIG. 15 is an explanatory view showing a soldering state to the printed board by the first nozzle of FIG. FIG. 16 is a perspective view showing the structure of another conventional first nozzle, FIG. 17 is an explanatory view showing a state in which molten solder of the first nozzle of FIG. 16 is jetted, and FIG.
Fig. 16 is an illustration showing soldering to a printed circuit board on which discrete type components have been mounted by the first nozzle, and Fig. 19 shows chip type (flat type) components mounted by the first nozzle on Fig. 16. It is explanatory drawing which shows the state of soldering to the printed printed circuit board. 21 ... Solder tank, 22 ... Heater 23 ... Molten solder, 24 ... Fin 25 ... First nozzle, 29 ... Printed circuit board 33 ... Nozzle plate, 34 ... Jet holes 34a ... First row jet holes 34b ... Second row Eye jet hole 34c ... Third row jet hole 35 ... Slit groove 36, Large diameter hole 37a-37d, 39a, 39c ... Nozzle plate piece 38a-38d, 40a-40c ... Recessed recess

Claims (1)

[Scope of utility model registration request] 1. A pressurizing unit for pressurizing molten solder contained in a solder bath, wherein the solder bath has a plurality of rows in a direction in which the printed circuit board on which electronic components are mounted is transported over the solder bath. A first nozzle for forming a solder jet wave of
In a jet-type automatic soldering device provided with a second nozzle that forms a single solder jet wave, as the first nozzle, a plurality of rows of narrow groove holes through which molten solder is jetted to a nozzle plate, and A jet flow characterized in that large-diameter holes having a diameter larger than the width of the narrow-groove holes are provided at appropriate intervals in the longitudinal direction of the narrow-groove holes, and the large-diameter holes in each narrow-groove hole are arranged in a staggered manner. Automatic soldering equipment.