JPH03226366A - Flux sprayer - Google Patents

Abstract

PURPOSE:To uniformly stick a flux liquid onto a printed circuit board and to improve the quality of the printed circuit board by providing a nozzle having an ejection port for ejecting the flux liquid and a supply opening to blow out air on a cylindrical body provided below the printed circuit board. CONSTITUTION:A pump 34 is driven to open a solenoid valve 36 and to eject the flux fluid 2 from the ejection port 28 of the nozzle 21 perpendicularly toward the rear surface of the printed circuit board 7. On the other hand, the air pressurized by a fan 35 is made into the spiral air by passing through grooves 27 of a partition plate 26 in the nozzle 21 and this air is blown out of the ejection port 29 and rises spirally. The flux liquid 2 ejected from the ejection port 28 is, therefore, made into the fine bubbles by the spiral air and is raised. Further, the air bubbles are ruptured by the spiral air and, therefore, the liquid flux is stuck in the mist form of fine particles to the printed circuit board 7. The circuit board is thus coated with the flux liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flux spraying device that sprays a flux liquid in the form of a mist and applies it to a printed circuit board.

[Prior Art] Fig. 4 is a side sectional view showing an example of a conventional flux coating device, in which 1 is a flux tank, 2 is a flux liquid, 3 is a porous foaming tube, and 4 is the foaming tube. foamed flux formed by blowing pressurized air in 3, 5
6 is a nozzle formed in the upper part of the foaming tank 5, 7 is a printed circuit board, 8 is an electronic component, 9 is a lead wire, and 10 is the lead wire 9.
This is the insertion hole.

The conventional flux applicator is constructed as described above, and the pressurized air in the foaming tube 3 is blown into the flux tank 1, causing the flux liquid 2 to foam and become foamed flux 4, which rises and flows inside the nozzle 6. is applied to the printed circuit board 7. Further, since the foaming height of the foamed flux 4 is set high, the running of the printed circuit board 7 is not hindered even if the length of the lead wire 1) is long.

[Problems to be Solved by the Invention] In the conventional flux coating device, in order to maintain the foaming height of the foamed flux 4 at a high level, the foamed flux 4 is placed at the nozzle 6.
The force of the fluid blowing out from the PC board becomes stronger and the amount of foaming increases, and therefore the amount of coating on the printed circuit board 7 also increases, causing the flux liquid 2 to flow from the periphery of the printed circuit board 7 to the top surface, or to cause the flux liquid 2 to flow from the insertion hole 10 of the printed circuit board 7 to the top surface. It oozes out,
There was a problem in that the flux liquid 2 adhered to the electronic components 8 on the upper surface of the printed circuit board 7 and had an adverse electrical effect on the electronic components 8.

For this reason, it is necessary to clean the top surface of the printed circuit board 7, and therefore the amount of cleaning liquid used increases, and the Freon (trade name of DuPont) liquid contained in the cleaning liquid is also consumed, and its use is regulated. There were problems in that pollution caused by the Freon liquid used in the cleaning process and increased costs due to the use of a large amount of cleaning liquid.

In addition, if the amount of foamed flux 4 generated is large (if the flux liquid 2 oxidizes or absorbs moisture in the air, the components and specific gravity will change in large quantities), which increases the amount of effort required to manage the flux liquid 2. There was a problem that the amount of

There is also a method of spraying the flux liquid 2 with a spray gun, but with this method, the particles of the flux liquid 2 are large, and the large particles scatter especially at the beginning of spraying, resulting in uneven adhesion to the printed circuit board 7. There was a problem that the amount of flux liquid 2 used increased due to splashing.

This invention was made in order to solve the above problems, and the flux liquid jetted from a nozzle is atomized by swirling air blown from around the nozzle, and the flux liquid is atomized and sprayed onto a printed circuit board. The purpose of this study is to obtain a flux spraying device that can be used to apply flux. In addition, the purpose is to spray in a direction perpendicular to the printed circuit board, and the purpose is to be able to change the size of the hood that covers the atomized flux liquid depending on the size of the printed circuit board. shall be.

[Means for Solving the Problems] A flux spraying device according to the present invention includes a cylinder provided below a printed circuit board, which includes a spout for spouting a pressurized flux liquid upward, and a flux spraying device for spouting a pressurized flux from the spout. In order to atomize the flux liquid, it is equipped with a nozzle provided with an outlet that blows out pressurized air from around the outlet.

In addition, it is effective to install the nozzle so as to spray in a direction perpendicular to the bottom surface of the printed circuit board, and furthermore, a hood is provided at the fixed position to cover the flux liquid sprayed upward from the nozzle and turned into a mist. It is preferable to provide a movable hood that can be moved according to the width of the printed circuit board.

[Operation] In this invention, the pressurized flux liquid and pressurized air are ejected from the nozzle, and the flux liquid becomes a fine mist and adheres to the printed circuit board, so it is difficult to apply the flux liquid to the printed circuit board. be done. Further, the flux liquid is sprayed in a direction perpendicular to the printed circuit board, and the hood on the movable side can be moved according to the width of the printed circuit board.

[Example J Figure 1 (at, (bl), Figure 2 (a) to (d)
, FIG. 3 shows an embodiment of the present invention, in which FIG. 1(a) is a plan view, FIG. 1(b) is a sectional view taken along line II in FIG. 1(a), and FIG. a) is an enlarged plan view of the nozzle in Fig. 1, Fig. 2(b) is a sectional view taken along the line ■-■ of Fig. A plan view and a side view showing the shape of the partition plate part in Figure (b), 3rd
The figure is a configuration diagram showing piping for cleaning liquid and pressurized air. In these figures, 1) shows the whole fluxer, 12 shows the transport chain on the fixed position side, and 13 shows the direction perpendicular to the running direction (six arrow directions) of the printed board 7 according to the width of the printed board 7. 12a is the transport chain 12 on the fixed position side that can move in the direction of arrow B);
13a is a holding claw of the transport chain 13 on the movable side, 14 is a chain guide on the fixed position side, 15 is a chain guide on the movable side, and 16 is a fixed position side integrated with the chain guide 14 on the fixed position side. The hood 17 is a hood on the movable side that is integrated with the chain guide 15 on the movable side, the hood 16 is divided into upper and lower parts at the chain guide 14, and the hood 17 is divided into upper and lower parts at the chain guide 15, so that the printed circuit board 7 can run. It looks like this. Reference numeral 18 denotes a recovery tank for recovering the excess sprayed flux liquid 2, and 19 denotes a duct for discharging the atomized flux liquid 2 scattered upward. 21
2 is a nozzle that sprays the flux liquid 2 in a mist form;
2 is the cylindrical body of the nozzle 21, and 23 is the flux liquid 2.
24 is a blower tube that blows out pressurized air; 25 is a lid that fixes the feed tube 23 and the blower tube 24 and closes one side of the cylindrical body 22; 26 is a partition that partitions the inside of the tube 22; The plate 27 is a spiral groove formed around the partition plate 26, and is formed so that the pressurized air blown out from the blast pipe 24 becomes spiral. 28 is a spout for spouting the flux liquid 2 spouted from the supply pipe 23;
Reference numeral 29 indicates an air outlet for blowing out the air that has become spiral in the groove 27, 3o indicates an air nozzle as a means for scattering the flux liquid 2 that has accumulated and adhered around the outlet 2 with pressurized air, and 31 indicates the above-mentioned Air nozzle 3° blast pipe,
32 is a storage tank containing the flux liquid 2; 33 is a supply pipe for the flux liquid 2; and 34 is a pump serving as means for supplying the fluff liquid 2 to the nozzle 21. 35 is a blower serving as a means for supplying pressurized air to the nozzle 21; 36;
3 is a solenoid valve that adjusts the flow rate of the flux liquid 2; 37 is an adjustment valve that adjusts the amount of air blown; 38 is a solenoid valve that adjusts the amount of air blown from the air nozzle 30; and 39 is a printed circuit board 7 that runs in the direction of arrow A. a first sensor that detects 40;
41 is a second sensor for detecting that the printed circuit board 7 is running on the fluxer 1), and 41 is each of the sensors 39, 4.
42 is a cooling device that cools the flux liquid 2 in the duct 19 and then turns it into powder. 43 is an exhaust fan.

Note that the nozzle 21 is configured so that the flux liquid 2 is sprayed in a direction perpendicular to the lower surface of the printed circuit board 7 even when the printed circuit board 7 is conveyed in an upward direction at a predetermined angle.

Next, the operation will be explained.

First, after driving the blower 35 to pressurize air, the regulating valve 37 is opened to supply pressurized air to the nozzle 21 .

When the first sensor 39 detects the printed circuit board 7 traveling in the direction of the arrow A, the control device 41 activates the 'RM
The I valve 38 is opened 8, and the excess flux liquid 2 adhering to the spout 28 is removed by pressurized air blown out from the air nozzle 30. After removing the flux liquid 2, the solenoid valve 38 is closed.

Next, the pump 34 is driven to open the solenoid valve 36, and the flux liquid 2 is jetted out from the spout 28 of the nozzle 21 in a direction perpendicular to the lower surface of the printed circuit board 7. On the other hand, the air pressurized by the blower 35 is passed through the partition plate 2 inside the nozzle 21.
By passing through the groove 27 of 6, it becomes a spiral shape, and the spout 29
Even if it blows out, it continues to rise in a spiral shape. Therefore, the flux liquid 2 ejected from the spout 028 rises as fine bubbles due to the swirling air, and these bubbles are further burst by the swirling air, so that the flux liquid 2 is turned into a mist of fine particles, and the printed circuit board 7 It is applied by adhering to.

In addition, since the flux liquid 2 in the form of mist rises in the swirling air, it does not scatter around and does not contaminate surrounding equipment.

Next, when the printed circuit board 7 running over the fluxer 1) is detected by the second sensor 40 and the printed circuit board 7 has finished passing over the fluxer 1), the control device 41 is activated to stop the pump 34. The solenoid valve 36 closes and spraying of the flux liquid 2 ends.

Incidentally, when the spraying is finished, the flux liquid 2 remaining around the spout 28 can be removed by opening the solenoid valve 38 again. Further, the atomized flux liquid 2 that has risen in a spiral shape is discharged from the duct 1a by driving the fan 43. The exhaust from the duct 1a may be an intermittent exhaust that is performed only when the flux liquid 2 is sprayed.Furthermore, since the amount of spray fins of the flux liquid 2 varies depending on the size of the printed circuit board 7, the exhaust amount is adjusted. You can also do that.

Furthermore, the discharged flux liquid 2 is cooled by a cooling device 42, pulverized, and recovered.

In addition, each hood 16 and 17 covers the atomized flux liquid 2 to prevent it from dispersing to the surroundings, and can immediately respond to changes in the width of the printed circuit board 7 by moving the hood 17 on the movable side. It is.

[Effects of the Invention] As explained above, the present invention has a cylindrical body provided below a printed circuit board, which has a spout for spouting a pressurized flux liquid upward, and the flux liquid spouted from the spout is atomized. In order to achieve this, the nozzle is equipped with an outlet that blows out pressurized air from around the outlet, so that the flux liquid becomes atomized and adheres uniformly to the printed circuit board, and it also protects the electronic components. Since the lead wires do not bleed upward from the insertion holes, it is possible to prevent the printed circuit board from being contaminated by flux liquid, and the nozzle is installed in a direction that sprays perpendicularly to the bottom surface of the printed circuit board, so that the printed circuit board is When conveying in an upward direction at a predetermined angle, the atomized flux liquid does not wrap around and adhere to the top surface of the printed circuit board, which has the advantage of improving the quality of the printed circuit board.

In addition, it is economical because the consumption of the cleaning liquid is reduced, and pollution caused by the Freon liquid contained in the cleaning liquid can also be reduced.

Furthermore, we have provided a hood on the fixed position side that covers the flux liquid that is sprayed upward from the nozzle and becomes a mist, and a hood on the movable side that can be moved according to the width of the printed circuit board, so it can accommodate the width of the printed circuit board. It has advantages such as being able to change the size of the hood.

[Brief explanation of drawings]

Figure 1 (al, (b), Figure 2 (a) - (dl)
, and FIG. 3 show an embodiment of the present invention, in which FIG. 1 (at is a plan view, and FIG.
2 (al is a plan view showing an enlarged view of the nozzle in FIG. 1, and FIG. 2 (b) is a cross-sectional view taken from ■-I in FIG. 2 (a).
Cross-sectional view taken along line I, Fig. 2(c), (di is the second
Figure fb) is a plan view and side view showing the shape of the partition plate portion, Figure 3 is a configuration diagram showing cleaning liquid and pressurized air piping, and Figure 4 is a side sectional view showing an example of a conventional flux coating device. It is. In the figure, 2 is a flux liquid, 7 is a printed circuit board, 1) is a fluxer, 16.17 is a hood, 19 is a duct, 21 is a nozzle, 22 is a cylinder, 23.33 is a supply pipe, 24 is a blower pipe, 26 is a partition plate, 27 is a groove, 28 is a blowout port, 29 is a blowout port, 30 is an air nozzle, 31 is a blow pipe, 32 is a storage tank,
34 is a pump, 35 is a blower, and 41 is a control device. Figure (a) Figure 1 (b)] 9 Massif Figure 4 Massif 0 Figure

Claims (3)

[Claims] (1) A fluxer for applying flux to a printed circuit board, in which a cylindrical body provided below the printed circuit board has a spout for spouting a pressurized flux liquid upward, and a flux liquid spouted from the spout. What is claimed is: 1. A flux spraying device comprising a nozzle provided with an outlet for blowing out pressurized air from around the outlet in order to atomize the flux. (2) The flux spraying device according to claim 1, wherein the nozzle is oriented in a direction perpendicular to the lower surface of the printed circuit board. (3) A hood is provided on the fixed position side to cover the flux liquid sprayed upward from the nozzle in the form of a mist, and a movable side hood that can be moved according to the width of the printed circuit board (claim 1). ) or the flux spraying device described in (2).