JP3159328B2 - Automatic soldering equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic soldering apparatus for soldering a printed circuit board or the like.

[0002]

2. Description of the Related Art Solder baths used in automatic soldering machines,
Especially in a solder bath where molten solder is jetted from a nozzle,
New solder is always jetted from the nozzle, and it comes into contact with air, so a large amount of solder oxide is generated around the nozzle, and the shaft immersion part of the pump that jets molten solder is agitated by the axis, A large amount of solder oxide is also generated around the shaft.

[0003] Oxide of solder (hereinafter simply referred to as oxide) is floating on the molten solder because of its lower specific gravity than that of the molten solder. Or soldering is hindered, resulting in defective soldering.

[0004] In order to suppress the generation of oxides in the solder bath,
It is only necessary to prevent the molten solder from coming into contact with air, and for this purpose, it has been customary to float a heat-resistant antioxidant oil (hereinafter simply referred to as oil) on the liquid surface of the molten solder (see: Actual). JP-B-51-40287).

However, if the oil is floated over the entire area of the solder bath, the oil may adhere to the printed circuit board, causing poor soldering, or the oil floating near the nozzle of the solder bath may be dropped after the jet flow. There is a problem that the area around the solder bath is soiled by being jumped off by the solder.

The present inventors have proposed a solder tank in which an upper part of a solder tank is partitioned and a lower tank is communicated with the lower part, and an oxide generated by a nozzle is introduced into the storage tank by a duct together with molten solder after jetting. (Japanese Patent Application No. 3-8336). Further, in connection with the present invention, there has also been proposed a solder tank in which an excessive amount of oil flows into a storage tank, and an oxide flows out of the solder tank together with the oil overflowing from the storage tank (Japanese Patent Application No. Hei.
No. 253012).

[0007]

By the way, a storage tank which partitions the upper part of the solder tank and communicates with the lower part is provided, and in the solder tank in which oil flows into the storage tank, the upper part of the solder tank is partitioned. Instead, the oil sometimes flowed into the other side. If oil is floated in the storage tank with the pump tank immersed in the molten solder on the side that separates the upper part of the solder tank and the other side is the nozzle side,
If the oil flows from the storage tank to the nozzle side, as described above, the oil may adhere to the printed circuit board, or may inconvenience the surroundings of the solder tank. The present invention intends to propose an automatic soldering apparatus in which a storage tank is formed by partitioning an upper portion and oil does not flow into the other side even if oil flows into the storage tank.

[0008]

Means and Action for Solving the Problems The present inventors have
In a solder tank with oil floating in a partitioned storage tank,
As a result of studying a phenomenon that oil can sink in the solder with much higher specific gravity than oil and flowing out to the adjacent part, which is not considered by common sense, the oil passes through the sinkhole of the solder. It was found to be leaked. In other words, the power of the automatic soldering apparatus is turned off when the operation is completed. However, the power supply to the heater of the solder bath is also cut off, and the molten solder solidifies.

The volume of the solder decreases when it solidifies,
This decrease appears in the last coagulated part as a nest. In some cases, the nest is formed on the nozzle side and the pump shaft side, which are separated by a partition plate.However, if these nests are close to each other with the partition plate in between and they are open below, the oil will pass through the opened nest. Even if you pass, it flows out to the other side.

Therefore, the inventors of the present invention set apart the nest formed on the other side from the storage tank, and even if the lower part of the nest formed on the storage tank advances to the other side, the oil is removed. The present invention has been completed by noting that oil does not flow into the other side if it is prevented from floating on the nozzle side.

An automatic soldering apparatus according to the present invention separates and separates an upper part of a solder bath provided with a nozzle from which a solder is jetted from a nozzle in a direction in which a substrate to be soldered travels, communicates a lower part, and removes oxide. It is an automatic soldering device that has a storage tank for collecting molten solder containing, and an antioxidant oil is floated in the storage tank, and an eave is provided under the partition forming the storage tank, and from the storage tank to the solder tank side This prevents the antioxidant oil from flowing out.
This makes it difficult for oil to flow to the nozzle side.

In the automatic soldering apparatus according to the present invention, the eaves provided at the lower part of the partition are inclined such that the storage tank side is upward (increased), so that the oil further flows out to the nozzle side. It becomes difficult. This is because, if the nest extends under the eaves, the oil floats up just above the melting point of the solder, but when hitting the eaves, it floats up on the pump side, which has a higher inclination of the eaves.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front sectional view of a solder bath according to the present invention, and FIG.
3 is a perspective view of a partition member used in the solder bath according to the present invention, FIG. 3 is a sectional view taken along line AA of FIG. 2, and FIG. 4 is a perspective view of the solder bath according to the present invention.

A nozzle 2, a pump 3, and a heater 4 are provided in a main body 1 of a solder bath. The nozzle 2 jets the molten solder sent by the pump 3 and solders the printed circuit board at the top of the jet. The pump 3 is placed at an end of a duct 5 below the nozzle, and is rotated by a motor (not shown) via a shaft 6.

A partition member 7 is provided at an end of the main body 1, that is, at a portion where the shaft 6 is immersed in the solder.
This partition member has a box shape with upper and lower portions, and is submerged in the solder with its upper portion being slightly exposed as shown in FIGS. Therefore, the partition piece 8 on the nozzle side of the partition member 7 is divided into the pump side and the nozzle side with the lower part communicating therewith. When oil O is stored on the pump side, the pump side becomes the storage tank T.

An eave 9 is provided at the lower end of the partition 8. The inclination α that the storage tank side becomes slightly higher on the eaves 9
If attached, it is possible to further prevent oil from flowing out to the nozzle side. The other side of the partition 8 is formed as a discharge port 10, where a discharge plate 11 is provided.

An oxide collecting duct 12 similar to that shown in Japanese Patent Application No. 3-8336 is installed in the nozzle 2 with its tip extending beyond the partition piece 8. An oil supply pipe 13 similar to that shown in Japanese Patent Application No. 3-253012 is installed near the partition 8 and on the storage tank side.

Next, prevention of oil outflow in the solder bath of the present invention will be described. When the power supply to the heater 4 in the solder bath is turned off, the molten solder solidifies, and drawholes S are formed at various places. The solder starts to solidify from the periphery of the solder bath from which heat is released, and finally solidifies in the central part where the heat release is low.

When the partition member 7 is installed in the solder bath and the solder bath is divided into two by the partition member 8 of the partition member, the partition member 8
Since the heat is released, the area around the partition piece solidifies quickly.
In addition, since the eaves 9 are provided at the lower portion of the partition 8, heat is transmitted from the eaves 9 to the partition 8 and is released, so that the eaves 9 around the eaves 9 can be quickly solidified. It will not be possible in the vicinity.

Moreover, when the eaves 9 are installed below the partition pieces 8, the thickness of the partition pieces becomes the same as that of the eaves by the width of the eaves. It does not go over to the nozzle side. Therefore,
The nest formed on the storage tank side and the nest formed on the nozzle side are not connected to each other across the eaves, and the oil on the storage tank side does not flow out to the nozzle side.

Further, if the eaves are inclined so that the storage tank becomes higher, as shown in FIG. 1, even if the burrow containing oil O up to the tip of the eaves passes over the partition piece, the solder melts when the solder melts. The oil floats right above and floats toward the storage tank along the inclination of the eaves.

In the embodiment, a box-shaped partition member is provided in the solder tank to form the storage tank. However, the storage tank may be formed only by partition pieces without using the partition member. Good. Also, in the embodiment, the eaves are shown on both the nozzle side and the storage tank side, but the eaves used in the present invention are only on one side of the partition piece, that is, only on the nozzle side, or only on the storage tank side. It goes without saying that what is available can be adopted.

[0023]

According to the present invention, the upper part of a solder bath provided with a nozzle for jetting solder is separated from the nozzle in the direction in which the substrate to be soldered travels, separated from the nozzle, communicates with the lower part, and contains an oxide. Set up a storage tank to collect molten solder,
An automatic soldering apparatus in which antioxidant oil floats in the storage tank, and an eave is provided at a lower portion of a partition forming the storage tank to prevent the antioxidant oil from flowing out of the storage tank to the solder tank side. Therefore, it is possible to obtain an automatic soldering apparatus having an excellent effect capable of sufficiently exerting the effect of the antioxidant oil and preventing the entire solder bath provided with the nozzle from being contaminated with the antioxidant oil. it can.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a solder bath according to the present invention.

FIG. 2 is a perspective view of a partition member used for a solder bath according to the present invention.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a perspective view of a solder bath according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solder tank main body 2 Nozzle 3 Pump 4 Heater 6 Pump shaft 7 Partition member 8 Partition piece 9 Eaves S Drawwell T Storage tank O Oil

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenichi Tomizuka 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Zen Mitsuo 23-23 Senjuhashi-do-cho, Adachi-ku, Tokyo Inside Industrial Co., Ltd. (72) Inventor Hidetoshi Nakamura 23, Senjuhashido-cho, Adachi-ku, Tokyo Inside Senju Metal Industry Co., Ltd. (56) References JP-A-60-191658 (JP, A) JP-A-61-147965 ( JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B23K 1/08 320 B23K 3/06 H05K 3/34 506

Claims (2)

(57) [Claims] 1. A reservoir for separating and separating an upper part of a solder bath provided with a nozzle for jetting solder from a nozzle in a direction in which a substrate to be soldered travels, communicating with a lower part, and collecting molten solder containing oxide. An automatic soldering apparatus comprising a tank and floating anti-oxidation oil in the storage tank, wherein an eave is provided at a lower portion of a partition forming the storage tank, and the anti-oxidation oil is transferred from the storage tank to the solder tank side. An automatic soldering device characterized by preventing oil from flowing out. 2. The automatic soldering apparatus according to claim 1, wherein the eaves are inclined such that the storage tank side is upward.