JPH0593655U - Jet solder bath - Google Patents

Abstract

(57) [Summary] [Purpose] The molten solder after jetting from the nozzle and the oxide generated here are received by the gutter and sent to the storage tank from the duct connected to the gutter so that the oxide is not deposited around the nozzle. And to prevent solder oxides from accumulating in the gutter. [Structure] A gutter 15 having an opening 16 formed substantially in the center is installed on a side portion of the nozzle 3, and an inclination (α) is provided on both sides of the opening so that the opening is lowered. The outlet 17 is connected to a discharge duct 18 extending to the storage tank 11.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a jet solder bath which is incorporated in an automatic soldering device to solder a printed circuit board.

[0002]

[Prior Art]

 In the jet solder bath, a nozzle and a jet pump are installed in the solder bath.The molten solder sent by the jet pump jets upward from the nozzle, and the jetted molten solder is brought into contact with the printed circuit board at a predetermined location. It is to be soldered to.

The solder melted in this solder bath has a high temperature of 200 ° C. or higher, and since it is jetted, it is dropped in a bath with a drop, so that it is a molten solder that drops. , The molten solder in the bath will be mixed. At this time, the molten solder also comes into contact with air more frequently, so that the molten solder is vigorously oxidized at the falling portion of the molten solder to form an oxide.

The solder that has been once oxidized in this way loses its function as a solder and must be discarded, resulting in a great economic loss. In addition, the oxide is accumulated near the nozzles, that is, between the nozzles and the solder bath, and when the nozzles are the primary jet nozzle and the secondary jet nozzle, they are accumulated between the nozzles. If too much of it accumulates, it will spill out of the lower wall of the solder bath to the outside of the bath, or it will adhere to the printed circuit board that comes into contact with the molten solder in the solder bath and interfere with soldering of the printed circuit board, and further, it will cause poor soldering. Was the cause of causing.

Therefore, in the conventional solder bath, an operator is always standing by near the solder bath, and if any oxide is accumulated, it is removed by a net or a spatula.

[0006] This oxide removal work must be carried out in a hurry because the printed circuit boards that are continuously transported to the operating automatic soldering device without interruption must be wiped out quickly. There were problems such as touching the printed circuit board and dropping an expensive printed circuit board into the molten solder to burn it, or splashing the molten solder to cause burns.

Therefore, the applicant of the present invention invented a jet solder bath capable of collecting oxides in the vicinity of the nozzle where they can be easily removed and removing the oxides without hindering the soldering work, and Japanese Patent Application No. 3-8336. As proposed.

In the structure of this jet solder bath, a gutter is provided on the side of the jet nozzle, the gutter is once connected to the duct, and the outlet of the duct is extended to the storage tank. In this solder bath, the molten solder and the oxide jetted from the nozzle fall into the gutter along the nozzle former, and the oxide rises from the gutter through the duct at the outlet of the duct and accumulates in the storage tank. Is becoming

[0009]

[Problems to be solved by the device]

 By the way, in this jet solder bath, the oxide flows out completely with the molten solder in the gutter installed on the entry side of the primary jet nozzle and the secondary jet nozzle (before the traveling direction of the printed circuit board). Oxides were sometimes deposited in the gutter installed on the exit side of the. An object of the present invention is to provide a jet solder bath in which oxide does not deposit even on the exit side of the secondary jet nozzle and completely flows out to the storage bath.

[0010]

[Means for Solving the Problems]

 As a result of investigating the cause of the oxides depositing in the gutter on the exit side in a jet solder bath that collects this oxide in one place, the inventor has found that the oxide with a low specific gravity floats on the molten solder while However, since the amount of molten solder flowing out to the exit side former is small, the oxide does not flow to the molten solder and adheres to the bottom surface and wall surface during the trough. It was found that the oxide that was carried later was deposited on the oxide.

Therefore, the present inventor has found that if the distance from the end of the gutter to the duct is shortened and the flow of the molten solder is urged, the oxide is carried to the duct without adhering to the gutter. Focusing on, the present invention was completed.

According to the present invention, a gutter for receiving molten solder after jetting is installed on a side portion of a jet nozzle, and an opening is formed in a substantially central portion of the gutter, and portions on both sides of the opening are formed as openings. It is a jet solder bath characterized in that it has a downwardly sloping slope, and that a discharge duct is connected to the opening, and that the duct has a terminal outlet extending to a storage tank.

[0013]

【Example】

 The present invention will be described below with reference to the drawings. 1 is a perspective view of a main portion of a jet solder bath of the present invention, FIG. 2 is a plan view of the jet solder bath of the present invention, and FIG. 3 is a sectional view taken along line XX of FIG.

A primary jet nozzle 2 and a secondary jet nozzle 3 are installed in the main body 1 of the jet solder bath of the present invention. The lower part of these jet nozzles is connected to a jet duct 5 having a jet pump 4 installed at one end, and the jet pump shaft 6 is interlocked with a motor (not shown) mounted outside the solder bath body 1. ing.

The primary jet nozzle 2 has a narrow jet port, and a rough wave device is installed therein so that the rough wave penetrates between the electronic components of the printed circuit board to eliminate unsoldered solder.

The secondary jet nozzle 3 has a wide jet port so that the jetted molten solder can gently flow, and repairs flicker, bridges, etc. generated by soldering of the primary jet nozzle. The entry-side former 7 in the direction (arrow A) in which the printed board enters the secondary jet nozzle is curved, and the exit-side former 8 on the opposite side is a wide flat surface.

Below both sides of the primary jet nozzle 2, there are installed gutters 9 and 9 for receiving melted chips after being jetted from the primary jet nozzle. The gutter 9 has an outlet 10 at the end connected to a discharge duct 12 extending to a storage tank 11. The molten solder after the jet flow and the oxides oxidized during the jet flow from the gutter 9 through the discharge duct 12 to be stored. It is transported to tank 11. Therefore, the oxide generated in the primary jet nozzle 2 accumulates in the storage tank without drifting in the vicinity of the nozzle.

Here, the storage tank is a jet pump side formed by partitioning the upper portion of the solder bath into a nozzle side and a jet pump side with a partition plate 13. However, the storage tank is not limited to the jet pump side, and may be any part formed by partitioning the upper part of the solder tank with a partition plate.

A gutter 14 is installed below the entrance-side former 7 of the secondary jet nozzle 3, and a gutter 15 is installed below the exit-side former 8 as well. A gutter (hereinafter referred to as an entrance gutter) 14 installed below the entrance former has the same structure as the gutter 9 installed in the primary jet nozzle.

A gutter (hereinafter referred to as an exit side gutter) 15 installed below the exit side former has an opening 16 formed substantially at the center thereof, and the slopes on both sides of the opening are such that the opening becomes low ( α) is attached. The outlet 16 of the opening 16 is connected to a discharge duct 18 extending to the storage tank 11.

A discharge pump 19 may be installed at the outlet 17 of the discharge duct 18. The discharge pump forcibly sucks the molten solder in the discharge duct and discharges it to the storage tank, and can give more force to the molten solder on the exit side gutter.

Next, the flow state of the oxide in the jet solder bath of the present invention having the above structure will be described.

The motors (not shown) rotate the pumps 4 and 4 of the primary jet nozzle 2 and the secondary jet nozzle 3 to jet molten solder from the respective nozzles. Since a large amount of molten solder jetted from the primary jet nozzle flows on both sides of the primary jet nozzle, this flow is vigorous, and the molten solder and the oxides generated there are gutters placed on both sides of the primary jet nozzle. 9 and 9 are sent to the storage tank 11 through the exhaust ducts 12 and 12, and the oxide floats in the storage tank 11.

Further, since a large amount of the molten solder jetted from the secondary jet nozzle and the oxide generated here flow toward the inlet side former 7, they are discharged from the inlet side trough 14 installed below this. It is sent vigorously to the storage tank 11 through the duct 12, and the oxide floats up in the storage tank.

On the other hand, a large amount of molten solder does not flow toward the exit side former 8 of the secondary jet nozzle 3, unlike the entrance side former 7. However, since the exit side gutter 15 has the opening 16 formed substantially in the center thereof, even a small amount of molten solder can immediately flow into the opening. Moreover, since the portions on both sides of the opening 16 are inclined so that the opening is lowered, the molten solder flowing in the gutter is given momentum.

When the molten solder flowing through the exit side gutter 15 is energized, the oxide is also flushed with the molten solder and does not adhere to the gutter. Then, the molten solder and the oxidized portion pass through the discharge duct 18 and enter the storage tank 11 through the outlet 17, where the oxide floats.

The oxide floating in the storage tank 11 does not flow toward the nozzle side and stays here because the partition plate 13 is present on the solder tank. When the oxides have accumulated in the storage tank, when necessary, scrape them with a net or scrape them with a spatula. Further, the oxides accumulated in the storage tank may be made to overflow the heat-resistant oil into the storage tank and may be discharged to the outside of the storage tank together with the overflowed heat-resistant oil.

In the embodiment, the jet solder bath having the primary jet nozzle and the secondary jet nozzle is installed, but the present invention is also applied to an overflow type jet solder bath in which molten solder overflows from a wide nozzle in all directions. It is possible.

[0029]

[Effect of the device]

 The jet solder bath of the present invention applies the momentum to the molten solder flowing through the trough to flow the oxide even if the amount of the molten solder after jetting from the nozzle is small, and since the distance of the trough is short, the molten solder immediately flows. It has an excellent effect that it does not flow into the duct from the gutter and deposit oxides on the gutter.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part of a jet solder bath according to the present invention.

FIG. 2 is a plan view of the jet solder bath of the present invention.

3 is a sectional view taken along line XX of FIG.

[Explanation of symbols]

 3 Secondary jet nozzle 7 Entry side former 8 Exit side former 11 Storage tank 13 Partition plate 14 Entry side gutter 15 Exit side gutter 16 Opening 17 Outlet 18 Ejection duct

Claims (1)

[Scope of utility model registration request] 1. A gutter for receiving molten solder after jetting is installed on a side portion of a jet nozzle, and an opening is formed at a substantially central portion of the gutter, and portions on both sides of the opening face toward the opening. A jet solder bath, characterized in that it has a lower slope, and that an outlet is connected to a discharge duct, and that the duct has an end outlet extending to a storage bath.