JPH0585262B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an automatic soldering device, and in particular to an automatic soldering device that does not cause a flow of molten solder in a direction perpendicular to the direction of movement of a soldering board at a nozzle from which molten solder is spouted. In addition, by partially changing the height of the wavefront of the molten solder, flux gas generated during soldering can be easily discharged, and the simple structure allows good soldering performance even for chip parts. This invention relates to a jet-type automatic soldering device.

Prior Art Conventionally, when soldering electronic components to a soldering board (hereinafter referred to as a board), flux is applied to the soldering surface, and when the flux comes into contact with high-temperature molten solder, a large amount of gas is generated. However, if there is no place for this gas to escape, the molten solder will not be able to contact the required soldering points, resulting in poor soldering.
This was particularly noticeable when soldering chip components in which no through holes were formed on the board.
In order to eliminate this drawback, conventionally, jet-type automatic soldering equipment was used, or jet-type jets and normal jets were used together, but with either method, the structure became complicated. However, sufficient soldering performance was still not achieved.

That is, as shown in FIG.
When the chip component 20 bonded to the substrate 3a is soldered using the jet type molten solder 3, the wave crest 19 of the molten solder 3 is directed in the traveling direction of the board 13 (arrow A).
Since the gas G generated between the chip parts 20 remains stationary between the chip parts 20 and is not discharged until it passes the wave crest 19, There was a soldering defect in some parts.

In order to eliminate these drawbacks, a method has been proposed in which molten solder is jetted out from multiple small holes drilled around a pipe, and the pipe is moved back and forth in a direction perpendicular to the direction in which the board travels (for example, Japanese Patent Publication No. 62 −15313)
However, according to this method, the molten solder flow reciprocates in a direction perpendicular to the direction in which the board travels, but the period of this reciprocating movement cannot be made very short, and in practice this period is extremely limited to about 1 second. Since the speed was set at a low speed, the gas removal effect could not be expected to be very effective.

Therefore, in Japanese Patent Application No. 58-249029 (Japanese Unexamined Patent Publication No. 60-145266), the applicant provided a nozzle opening control member and used the opening control member to control the speed of the wavefront of the molten solder in the traveling direction of the board. We have proposed an automatic soldering device that can efficiently eliminate flux gas by reciprocating the flux gas, but this invention requires a pulse motor, microcomputer, etc. for the drive section of the opening control member, so the performance is poor. Although this method is extremely superior, it is expensive and can only be used in some high-end models.

In addition, as another conventional example, the above-mentioned Japanese Patent Publication No. 62-15313 and the molten solder flow are moved in a direction perpendicular to the advancing direction of the board by rotating a spiral rotating shaft within a nozzle from which molten solder is spouted. Although there is a Japanese Patent Application No. 62-3049 filed by the present applicant, these conventional examples aim to eliminate flux gas by actively flowing molten solder in a direction perpendicular to the direction in which the board travels. The structure is completely different from the invention.

Further, Japanese Utility Model Application No. 61-41458 discloses a jet-type automatic soldering device in which a rotor is provided inside the solder spout of the jet-type automatic soldering device.
The structure is different from the present invention because the blades fixed around the rotor are arranged with specific leads like screws, and when the leads are attached to the blades in this way, molten solder flows. Since the blade is always present as an obstacle to the flow in the part where the molten solder is to be melted, the flow of the molten solder is poor and the height of the wave crest of the molten solder is not as high as expected. . Furthermore, since there is no current plate for the molten solder below the rotor, the pressure of the molten solder in the width direction of the nozzle is not constant, resulting in problems in that the wave crests of the ejected molten solder do not have a stable height.

Purpose The present invention has been made in order to eliminate the drawbacks of the above-mentioned prior art, and its purpose is to provide a rotating shaft at the opening of a nozzle through which molten solder is spouted. In an automatic soldering device that rotates a shaft, a plurality of parallel rotary plates having no twisted leads in the axial direction are fixed around the circumference, and molten solder is scraped up by rotation around the parallel rotary plates. A rotary shaft formed with a notch recessed in the normal direction of the nozzle is rotatably disposed at the opening of the nozzle so as to rotate in the molten solder, and the crest of the wave of the molten solder spouted from between the parallel rotating plates is rotated in the molten solder. height and
By configuring the height of the wave crest of the molten solder scraped up by the notch of the parallel rotating plate to alternately change in height, the molten solder spouted from the nozzle is directed in a direction perpendicular to the traveling direction of the substrate. By simply making multiple small waves move up and down alternately and flowing vigorously in the opposite direction to the direction in which the board is traveling, flux gas generated during soldering of chip components can be removed extremely efficiently. Another object of the present invention is to provide a low-cost jet-type automatic soldering device that can simplify the structure of a rotating shaft and perfectly solder chip parts.

Another purpose is to rectify the flow of molten solder before it is ejected from the nozzle by arranging a rectifier plate with a plurality of holes formed below the opening of the nozzle through which the molten solder is ejected. By ejecting the rectified molten solder from the nozzle through a parallel rotating plate, the height of the wave crest of the molten solder in the width direction of the nozzle is stabilized, and even though the height of the molten solder varies minutely, it is extremely stable. The goal is to obtain the crest of the wave.

Configuration In summary, the present invention provides an automatic soldering device in which a rotating shaft is arranged at the opening of a nozzle through which molten solder is spouted, and the rotating shaft is rotated. A parallel rotating plate is fixed around the parallel rotating plate, and at least one place around the parallel rotating plate is recessed in the normal direction for scraping up the molten solder by rotation, and aligned in the axial direction in the plurality of parallel rotating plates. The rotating shaft formed with a cutout is rotatably disposed in the opening of the nozzle so as to rotate in the molten solder, and a plurality of small holes are formed below the opening. A rectifying plate is provided, and the flow of the molten solder rectified by the rectifying plate is sent to the opening of the nozzle, and the height of the wave crest of the molten solder spouted from between the parallel rotating plates and the height of the wave crest of the molten solder spouted from between the parallel rotating plates are determined. The present invention is characterized in that the height of the wave crest of the molten solder scraped up by the notch changes alternately.

The present invention will be explained below based on embodiments shown in the drawings. As shown in FIGS. 1 to 4, an automatic soldering device 1 according to the present invention has a rotating shaft 4 disposed in an opening 2a of a nozzle 2 through which molten solder 3 is spouted. In an automatic soldering device configured to rotate, a plurality of parallel rotary plates 5 having no twisted leads in the axial direction are fixed around their periphery 4a, and at least one location on the periphery 5a of the parallel rotary plates 5 is rotated. A rotary shaft 4 formed by forming notches 5b aligned in the axial direction in a plurality of parallel rotary plates 5 in the normal direction for scraping up the molten solder 3 is placed in the molten solder 3 so that its upper surface is in the traveling direction of the substrate 13. The height of the wave crest 19 of the molten solder 3 spouted from the gap 7 of the parallel rotating plate 5, and the wave crest of the molten solder 3 scraped up by the notch 5b of the parallel rotating plate 5. 19 is configured so that the height changes alternately.

As shown in FIG. 3, the parallel rotating plates 5 each have no leads in the axial direction of the rotating shaft 4, and all of them are aligned perpendicularly to the rotating shaft 4 and rotate around the rotating shaft. 4a by means such as welding. Note that the gap 7 between these is formed to be larger than the plate thickness of the parallel rotating plate 5, so that the molten solder 3 can be sufficiently spouted from the gap 7. In the illustrated embodiment, the parallel rotating plate 5 has cutouts 5b provided at three locations around the circumference 5a at 120° intervals; That's fine. Further, it may be provided at two locations, four locations, etc. The reason why the parallel rotary plate 5 having no torsional leads in the axial direction is fixed around the circumference 4a of the rotary shaft 4 is to make the manufacture of the rotary shaft 4 easier and to obtain a sufficient flux gas G removal effect. This is to reduce the cost.

The rotating shaft 4 is supported by bearings 6 and 8 attached to the ends 2b and 2c of the nozzle 2, and one end 4b of the rotating shaft 4 extends toward the front in the figure, and a motor M is connected to the one end. are directly connected to each other, and the motor is fixed to the solder tank 10. The rotary shaft 4 is rotated by the motor M, for example, in one direction at an appropriate speed.

As an example, the diameter of the rotating shaft 4 is 5 mmφ, the diameter of the parallel rotating plate 5 is 9 mmφ, the thickness of the parallel rotating plate 5 is 1 mm, and the interval between each parallel rotating plate 5, that is, the gap 7 is 3 mm.
mm, set to

In FIG. 2, a current plate 22 is disposed below the opening 2a of the nozzle 2, and a plurality of small holes 22a are formed in the current plate. Also nozzle 2
The lower part thereof is formed as an intermediate layer 23, and an impeller 24 rotatably driven by a motor (not shown) is disposed in the intermediate layer, and below the impeller, molten solder is applied. A hole 23a is formed for sucking up No. 3 from below as shown by arrow B. The molten solder 3 sucked up as shown by arrow B is blown up as shown by arrow C towards the current plate 22.

In FIG. 1, in addition to the nozzle 2, a nozzle 25 for secondary soldering is provided in the solder tank 10. The substrate 13 is configured to advance in the direction of arrow A and move from the nozzle 2 to the nozzle 25, where primary soldering and secondary soldering are performed.

Effects The present invention is configured as described above, and its effects will be explained below. When the impeller 24 is rotated by the motor, the molten solder 3 in the solder bath 10
is sucked up from the hole 23a as shown by arrow B, blown up from the intermediate layer 23 toward the rectifying plate 22 as shown by arrow C, and is rectified through a large number of small holes 22a, and the pressure is increased in the width direction of the nozzle 2. It reaches the opening 2a of the nozzle 2 in a constant state, and is ejected upward from the opening, and the wave crests 19 are split on both sides of the rotation axis 4 and extend in both left and right directions of the nozzle 2 in FIG. It flows back into the solder tank 10. In this case, when the rotating shaft 4 to which a plurality of parallel rotating plates 5 are fixed in the molten solder 3 spouted from the opening 2a rotates, for example, in the direction of arrow D as shown in FIG. has no torsional leads in the axial direction of the rotating shaft 4, so the substrate 1 is rotated by the rotation of the parallel rotating plate 5.
Although the molten solder 3 does not move in the direction perpendicular to the traveling direction of the molten solder 3, the molten solder 3 is mainly blown up from the space 7 between the parallel rotating plates 5, and under normal conditions, the wave crest of the molten solder 3 that is blown up from the space 7 during this time. 19 small waves 19a are higher than directly above the parallel rotating plate 5. Therefore, when the parallel rotating plate 5 is at the top of the rotating shaft 4, the part of the small wave 19a of the molten solder 3 blown up from the gap 7 becomes high, and the small wave 19a directly above the part where the parallel rotating plate 5 is located becomes high. 19b becomes low. However, as the notch 5b of the parallel rotating plate rotates as shown by arrow D, the molten solder 3 is rotated together with the parallel rotating plate 5 due to the large surface tension of the molten solder 3, and the molten solder is rotated in the direction of movement of the board 13. When this scraped up molten solder 3 forms a wave crest 19, the small wave 19b becomes higher than the small wave 19a.

In this way, by rotating the parallel rotating plate 5, which has notches 5b at three places around the rotating shaft 4, together with the rotating shaft, the small waves 19b become higher per rotation of the rotating shaft. The frequency can be set to three times, and as a result, the frequency at which the small waves 19a and 19b alternate in height becomes three times per rotation of the rotating shaft 4. By rotating the rotating shaft 4 having the parallel rotating plates 5 in the molten solder 3 ejected from the nozzle 2 in this way, small waves 19a of molten solder are ejected from between the parallel rotating plates 5.
The height of the small waves 19b stirred up by the parallel rotary plate itself can be alternately changed, and the molten solder 3 can flow in the opposite direction to the direction in which the substrate 13 travels, resulting in intense movement at the wave crest 19. can be made to

As a result, as shown in FIG.
The flux gas G generated between the chip parts 20 mounted on the chip parts 3a is efficiently removed, and a sufficient flux gas removal effect can be obtained by the extremely simple configuration of the rotating shaft 4.
Then, the molten solder 3 adheres to all the required soldering points on the board 13, and complete soldering is performed.

Effects The present invention provides an automatic soldering device in which a rotating shaft is arranged at the opening of the nozzle through which molten solder is spouted as described above, and the rotating shaft is rotated.
A plurality of parallel rotating plates having no twisted leads in the axial direction are fixed around the circumference thereof, and a notch recessed in the normal direction is formed around the parallel rotating plates for scraping up molten solder by rotation. A rotating shaft is rotatably disposed in the opening of the nozzle so as to rotate in the molten solder, and the height of the wave crest of the molten solder spouted from between the parallel rotating plates and the notch of the parallel rotating plates are Since the height of the wave crest of the molten solder being scraped up alternately changes in height, the molten solder ejected from the nozzle is not moved in any direction perpendicular to the traveling direction of the board, but simply multiple small waves. By alternately moving up and down and causing a strong flow in the direction opposite to the direction in which the board travels, an effect can be obtained in which flux gas generated during soldering of chip components can be removed extremely efficiently. Further, as a result, the structure of the rotating shaft can be further simplified, and it is possible to provide an inexpensive jet-type automatic soldering device that can perfectly solder chip parts.

In addition, a rectifier plate with a plurality of holes is installed below the opening of the nozzle from which molten solder is spouted, so the flow of molten solder is rectified before it is ejected from the nozzle. The solder can be ejected from the nozzle through the parallel rotating plate, and the height of the wave crest of the molten solder in the width direction of the nozzle is stabilized.
This has the effect of providing a very stable wave crest of molten solder even though the height varies minutely.

[Brief explanation of the drawing]

1 to 3 relate to an embodiment of the present invention, FIG. 1 is a perspective view of the main parts of an automatic soldering device, and FIG. 2 is a main part of the automatic soldering device showing a state in which soldering is performed. Fig. 3 is a vertical cross-sectional view, and Fig. 3 is a perspective view schematically showing the vertical changes of the rotation axis and the small wave crest during rotation, and Fig. 4 shows the mutual relationship between the rotation axis and the change of the small wave crest. FIG. 5 is a side view showing the state of soldering of chip components according to a conventional example. 1 is an automatic soldering device, 2 is a nozzle, 2a is an opening of the nozzle, 3 is molten solder, 4 is a rotating shaft, 4a
5 is a periphery, 5 is a parallel rotating plate, 5a is a periphery, 5b is a notch, 7 is between rotating plates, 19 is a wave crest, 22 is a rectifying plate, and 22a is a child hole.

Claims (1)

[Claims] 1. In an automatic soldering device in which a rotating shaft is arranged at the opening of a nozzle through which molten solder is spouted and the rotating shaft is rotated, a plurality of parallel rotating plates having no twisted leads in the axial direction are connected to the rotating shaft. a notch fixed to the periphery of the parallel rotary plate and recessed in the normal direction for scraping up the molten solder by rotation at at least one location around the parallel rotary plate and aligned in the axial direction in the plurality of parallel rotary plates; The rotating shaft is rotatably disposed at the opening of the nozzle so as to rotate in the molten solder, and a rectifying plate having a plurality of small holes is disposed below the opening. , the flow of the molten solder rectified by the rectifier plate is sent to the opening of the nozzle, and the height of the wave crest of the molten solder spouted from between the parallel rotating plates and the notch of the parallel rotating plate are determined. An automatic soldering device characterized in that the height of the wave crest of the molten solder being scraped up alternately changes in height.