JPH0666863U - Jet solder bath - Google Patents

Abstract

(57) [Abstract] [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 to prevent the oxide from depositing around the nozzle. Moreover, prevent the oxide of solder from accumulating in the gutter. [Structure] A discharge duct 1 in which a gutter 15 is installed on a side of a nozzle 3 and an outlet 17 at an end of the gutter 15 extends to a storage tank 11.
8 is connected, and the suction pump 1 is sucked into the outlet 17.
9 is installed.

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 solder sent by the jet pump jets upward from the nozzle. It is a device that solders to the place.

The solder melted in the solder bath has a high temperature of 200 ° C. or higher, and since it is jetted, it is dropped into 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, respectively. If too much of it accumulates, it will spill from 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 hinder the soldering of the printed circuit board. This was a cause of defective soldering.

Therefore, in the conventional solder bath, an operator is always standing by near the solder bath, and if any oxide is collected, it is removed with 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 are continuously wiped out. There were problems such as touching the printed circuit board and dropping the 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 accumulated in the vicinity of the nozzle in a place where it can be easily removed, and proposed it as Japanese Patent Application No. 3-8336.

The structure of this jet solder bath is such that a gutter is provided on the side of the jet nozzle, one end of the gutter is 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 collects in the storage tank. It is like this.

[0009]

[Problems to be solved by the device]

 By the way, in this jet solder bath, in the gutter installed on the entry side of the primary jet nozzle and the secondary jet nozzle (in front of the traveling direction of the printed circuit board), the oxide completely flows out into the storage bath together with the molten solder. Oxides were sometimes accumulated in the gutter installed on the exit side of the next jet nozzle. 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 extensive studies on the cause of oxide deposition in the gutter on the exit side of the conventional jet solder bath, the present inventor has found that the oxide having a low specific gravity floats on the molten solder and flows with the molten solder. However, since the amount of molten solder flowing out to the exit-side former is small after the jet flow, the oxide adheres to the bottom surface and wall surface of the gutter in the middle of the gutter, and the oxide adheres to this oxide afterwards. It was found that the oxides that were carried adhered and accumulated.

Therefore, the present inventor completed the present invention by paying attention to the fact that if momentum is applied to the molten solder flowing in the gutter, the oxide will also flow together with the vigorous molten solder and will not be deposited in the gutter.

According to the present invention, a gutter for receiving molten solder after jetting is installed on the side of a jet nozzle, and the gutter is connected to a duct whose outlet is extended to an oxide storage tank. In addition, the jet solder bath is characterized in that a suction pump is installed at the outlet of the duct.

[0013]

【Example】

 The present invention will be described below with reference to the drawings. 1 is a perspective view of an essential part 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. 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 linked to a motor (not shown) mounted outside the solder bath main 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 flows gently, 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 horizontal.

Below both sides of the primary jet nozzle 2, there are installed gutters 9 and 9 for receiving the melted chips after being jetted from the primary jet nozzle. The outlet 9 of the gutter 9 is connected to a discharge duct 12 extending to a storage tank 11, and molten solder after jetting and oxides oxidized at the time of jetting are accumulated from the gutter 9 through the discharge duct 12. It is transported to tank 11. Therefore, the oxide generated in the primary jet solder 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, but 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. The gutter (hereinafter referred to as the entrance side gutter) 14 installed below the entrance side former has the same structure as the gutter 9 installed in the sluice of the primary jet.

A gutter 15 (hereinafter referred to as an exit side gutter) 15 installed below the exit side former 8 has an opening 16 formed substantially at the center thereof, and portions on both sides of the opening are inclined so that the opening becomes low. Is attached. The outlet 16 of the opening 16 is connected to a discharge duct 18 extending to the storage tank 11.

A suction pump 19 is installed above the outlet 17. The suction pump 19 sucks the molten solder in the discharge duct 18 and discharges it to the storage tank 11.

The suction pump shaft 20 is linked with the pump shaft 6 of the secondary jet nozzle 3 by a chain 21. Therefore, when the pump shaft 6 of the secondary jet nozzle is rotated, the suction pump shaft 20 is also rotated, and the suction pump 19 discharges the molten solder in the discharge duct 18 to the storage tank 11.

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

A motor (not shown) rotates pumps 4 and 4 of the primary jet nozzle 2 and the secondary jet nozzle 3 to jet molten solder from the respective nozzles. A large amount of molten solder jetted from the primary jet nozzle and oxides oxidized here flow on both sides of the primary jet nozzle, and this flow is vigorous, so the gutters 9 and 9 installed on the lower sides of both sides of the primary jet nozzle. Is sent vigorously to the storage tank 11 through the exhaust ducts 12 and 12, and the oxide floats in the storage tank.

Further, a large amount of the molten solder jetted from the secondary jet nozzle and the oxides oxidized here flow toward the inlet side former 7, so that the discharge duct 12 is discharged from the gutter 14 installed below this. Through it, it is vigorously sent to the storage tank 11, 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, a suction pump 19 is installed at the outlet 17 of the discharge duct 18 connected to the gutter 15 below the exit side former 8, and the suction pump forcibly sucks the molten solder in the discharge duct. Therefore, the molten solder dropped on the gutter 15 vigorously flows into the discharge duct even if the amount is small.

In the embodiment, the solder bath having the primary jet nozzle and the secondary jet nozzle is shown, but the present invention is also applicable to an overflow solder bath in which molten solder flows out from a wide nozzle in all directions. .

[0027]

[Effects of the Invention] The jet solder bath of the present invention has a suction pump installed at the outlet of the discharge duct that guides the molten solder and the oxide to the storage tank even if the amount of the molten solder after jetting from the nozzle is small. Since the molten solder and oxide in the discharge duct can be forcibly discharged to the storage tank, even if the amount of molten solder after the jet is small, as in the exit side of the secondary jet nozzle, the molten solder in the gutter is small. Is vigorously drawn into the exhaust duct. Therefore, in the jet solder bath of the present invention, the oxide dropped in the gutter does not flow into the discharge duct together with the vigorous molten solder, and the oxide is not deposited in 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 cross-sectional view taken along line XX of FIG.

[Explanation of symbols] 3 Secondary jet nozzle 7 Entry side former 8 Exit side former 11 Reservoir 12 Discharge duct 13 Partition plate 14, 15 Gutter 17 Outlet 18 Discharge duct 19 Suction pump 20 Suction pump shaft

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[Procedure amendment]

[Submission date] March 10, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Name of device

[Correction method] Change

[Correction content]

[Name of device] Jet solder bath

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 the gutter has an outlet connected to a duct extending to an oxide storage tank.
A jet solder bath with a suction pump installed at the outlet of the duct.