JPH034437Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a solder bath that makes it possible to solder a printed circuit board on which electronic components with lead wires and chip components are mounted together.

[Conventional technology]

Conventionally, there are two types: the flow dip method, in which the solder melt overflows into the solder bath, and the jet method, which forms jet waves of the solder melt.The flow dip method is suitable for soldering printed circuit boards on which electronic components with long lead wires are mounted. The jet type was used for soldering printed circuit boards with short lead wires or electronic components or chip components.

[Problem that the invention attempts to solve]

By the way, when soldering to a printed circuit board on which electronic components with long lead wires and chip components are mixed, it is better to solder in a flow dip type solder bath for electronic components with long lead wires, but In the case of chip parts, the part behind the chip part in the running direction of the printed circuit board and the parts where each chip part is close to each other are shaped like recesses, where air and other gases accumulate and cause soldering. There was a problem in that the melt did not adhere, or even if it did, it sometimes formed cavities and did not adhere completely.

In addition, jet-type soldering baths have the height of the jet waves set in accordance with the soldering surface of chip components, so it is good for electronic components with short lead wires, but if the lead wires are long, soldering The lead wires may get caught in the jet openings that jet the melt or the guide plates that form the jet waves, which may impede the conveyance of the printed circuit board or damage electronic components. To avoid this, raise the running level of the printed circuit board to a height where the lead wire does not get caught in the jet port.
If you increase the level of the jet wave by increasing the jetting force of the solder melt, the jet wave will become rough, inconsistent, and uneven, making it difficult to solder both electronic components with long lead wires and chip components. Therefore, good soldering was not possible. Also, since the solder melt becomes rough, a large amount of oxides are generated, resulting in increased consumption of the solder melt. Therefore, it is necessary to cut or bend the long lead wires to a predetermined length in advance, but cutting or bending the lead wires before soldering may cause the lead wires to attach to the printed circuit board. There was a problem in that the workability was very poor compared to the process of cutting with a cutter after soldering.

For this reason, in the case of printed circuit boards on which electronic components with long lead wires and chip components are mounted together, the electronic components with long lead wires are soldered in a flow dip type soldering bath, and then cut with a cutter. Since the chip parts must be soldered, two solder baths are required, which consumes a lot of the solder melt, and also requires a large amount of heat source consumption for heating the solder baths.

This idea was made in order to solve the above problem, and even if it is a printed circuit board on which electronic components and chip components with long lead wires are mixed, there is no need to cut or bend the lead wires in advance. The purpose is to obtain a soldering bath that can perform soldering with one soldering bath.

[Means for solving problems]

The solder bath according to this invention is provided with a solder bath body containing a solder melt, and an overflow surface is formed by causing the solder melt to flow out from an outlet formed at one end and overflow into the solder bath body. A flow dip tank is provided within the solder bath body, a jet tank is provided adjacent to the flow dip tank, and the jet tank is provided with a jet port that generates a large number of jet waves on the overflow surface formed in the flow dip tank, and an outflow port of the flow dip tank is provided adjacent to the flow dip tank. A rotary plate is rotatably provided at the outlet, and is rotated by the difference between the outflow force of the solder melt flowing out from the outlet and the outlet force of the solder melt ejected from the jet outlet of the jet tank.

[Effect]

In this invention, the solder melt flowing out of the flow dip tank flows in only one direction. Also,
The rotary plate can be rotated by the ejection of jet waves and used as a jet solder bath. In addition, the overflow surface flowing out from the flow dip tank is pushed up by the melted solder jetting out from the jet opening, forming jet waves, which are used to solder electronic components with long lead wires attached to printed circuit boards. Also, the chip components mounted on the printed circuit board are soldered, and air bubbles in the chip components are removed.

〔Example〕

Fig. 1 is a plan view showing an embodiment of this invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 1, and Fig. 4 is a sectional view taken along the - line in Fig. 1. FIG. In these figures, 1 is a printed circuit board, 2 is an electronic component, 3 is a lead wire, 4 is a chip component, and 5 is the entire solder bath. 6 is the solder tank body of the solder tank 5, 7 is the solder melt, 8 is a flow dip tank provided in the solder tank body 6, and 9 is the flow dip tank 8.
At the outlet formed on one end side, the solder tank body 6
The liquid level of the solder melt 7 inside is raised to create an overflow surface 7a.
form. 10 is a jet tank provided adjacent to the flow dip tank 8, and 11 is a large number of jet ports formed in a staggered manner over the entire upper surface of the jet tank 10, which are immersed in the solder melt 7. The solder melt 7 ejected from the jet port 11 flows out from the outflow port 9 and pushes up the overflow surface 7a formed above the jet port 11 to form a large number of jet waves 7b. Reference numeral 12 denotes a rotating plate provided between one end of the flow dip tank 8 and the jet tank 10, which controls the flow force of the solder melt 7 flowing out from the outlet 9 of the flow dip tank 8 and the jet port 11 of the jet tank 10. Solder melt 7 gushing out from
It is rotated by the difference between the ejection force and the ejection force. 13 is a flow pipe of the flow dip tank 8;
4 is a flow tube of the jet tank 10, 15 is an impeller provided in the flow tube 13, and 16 is an impeller provided in the flow tube 14, all of which pressurize the solder melt 7. 17 is a reflux port formed below the impeller 15, 18 is a reflux port formed below the impeller 16, and 19 is a reflux port formed when the printed circuit board 1 is transported by a transport chain (not shown) in the direction of arrow A. Shows the running trajectory.

Next, the operation will be explained.

The solder melt 7 in the solder tank main body 6 is pressurized by rotating impellers 15 and 16 driven by a motor (not shown), and passes through each flow pipe 13 and 14 to a flow dip tank 8 and a jet tank 10. Go inside. Then, the solder melt 7 entered into the flow dip tank 8.
rises and rotates the rotary plate 12 in the direction of arrow B in FIG. The entire upper surface of the jet tank 10 is covered, and the overflowing solder melt 7 is poured into the solder tank main body 6.
Then, it enters the reflux port 17 and is sent out into the flow pipe 13 again by the pressurization of the impeller 15.
On the other hand, the solder melt 7 that has entered the jet tank 10 is jetted out from the jet port 11 in the direction of arrow C, and the overflow surface 7a on the upper surface is
is pushed up to form a large number of jet waves 7b.

In this way, the jet wave 7b is formed on the overflow surface 7a.
The printed circuit board 1 passes through the place where the
The lead wires 3 and the chip components 4 are soldered.

Next, a case will be described in which the solder bath 5 of this invention is applied to a round type soldering device.

First, the electronic components 2 are mounted on the printed circuit board 1, the lead wires 3 are made to protrude downward, and the chip components 4 are temporarily attached to the bottom surface of the printed circuit board 1 with adhesive, etc., and then dried and subjected to flux treatment. Preheating is performed, and the solder is transferred to the solder bath 5. In the solder tank 5, the printed circuit board 1 advances in the direction of the arrow A, is conveyed along a trajectory 19 shown by a two-dot chain line, and descends from a horizontal direction to an oblique direction, is immersed in the solder melt 7, and connects the lead wires 3 and the printed circuit board 1. are soldered, and the chip component 4 is in a temporarily attached state. At this time, either reduce the pressure applied to the solder melt 7 in the jet tank 10 so as not to generate jet waves 7b on the overflow surface 7a, or
Alternatively, the first soldering is performed to the extent that a very small jet wave 7b is generated. Next, the printed circuit board 1 is raised diagonally, and after cutting the lead wires 3 fixed to the printed circuit board 1 by soldering with a cutter (not shown), it goes around the soldering device and returns to the solder bath 5 again. descend diagonally. At this time, the solder melt 7 in the jet tank 10 is pressurized to generate jet waves 7b, and the jet waves 7b ejected from a large number of jet ports 11 formed in a staggered manner cause the chip components 4 and the printed circuit board to 1
The second soldering is performed by removing air bubbles between the two and completely soldering the parts to which the solder melt 7 has not adhered. Then,
The printed circuit board 1 that has been soldered rises diagonally, travels horizontally, and advances to the next cooling device (not shown).

Further, the pressurized solder melt 7 overflows from the flow dip tank 8 due to the jet force ejected from the jet port 11 in the direction of arrow C, and covers the upper surface of the jet tank 10 to form an overflow surface 7a. Since the solder melt 7 is pushed up, a jet wave 7b is formed.

Furthermore, the jet wave 7b of a desired size can be obtained by adjusting the pressure applied by the impeller 16.

In addition, if the pressure applied to the solder melt 7 by the impeller 16 is made very small or stopped, the impeller 1
The rotating plate 1 is rotated by the pressing force of the solder melt 7 by
2 rotates in the direction of arrow B, and the upper surface of the jet port 11 becomes only the overflow surface 7a, so it becomes a flow dip type soldering device, and it is used to solder the printed circuit board 1 on which the electronic component 2 having the lead wire 3 is attached. Can be used as

In addition, if the pressure applied to the solder melt 7 by the impeller 15 is made very small or stopped, the impeller 1
The rotating plate 12 is
rotates in the direction opposite to the direction of arrow B and blocks the outflow port 9, leaving only the upper jet wave 7b of the jet port 11, resulting in a jet-type soldering device and the printed circuit board 1 on which the chip component 4 is attached. Can be used for soldering.

[Effect of idea]

As explained above, this invention provides a solder bath body containing solder melt, and forms an overflow surface by allowing the solder melt to flow out from an outlet formed at one end and overflow into the solder bath body. A flow dip tank is provided in the solder bath body, and a jet tank is provided adjacent to the flow dip tank, and the jet tank is provided with a jet port that generates a large number of jet waves on the overflow surface formed in the flow dip tank. A rotating plate is rotatably provided at the outlet, which is rotated by the difference between the force of the solder melt flowing out from the outlet and the force of the solder melt flowing out from the jet port of the jet tank. The oxide film and solder scum of the solder melt generated on the flow surface are swept away in one direction by the solder flow, and can be prevented from staying on the overflow surface.

In addition, on printed circuit boards where electronic components with long lead wires and chip components are mounted together, soldering can be done without cutting the lead wires short in advance. The productivity of printed circuit boards on which components and chip components are mixed is significantly improved.

In addition, since a single soldering bath can have both flow dip type and jet type soldering baths, it can also be used for soldering printed circuit boards that have only electronic components with lead wires or only chip components mounted. can.

In addition, by providing the rotary plate, the flow dip type solder melt is not pressurized, and only the solder melt in the jet tank is pressurized, thereby functioning as an independent jet type solder tank.

Furthermore, in round type soldering equipment, primary and secondary soldering can be performed in one soldering bath, so both
It is not necessary to attach a soldering tank to the stand, making the soldering apparatus more compact, reducing consumption of the solder melt due to oxidation, and having the advantage of requiring less heat source for heating.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an embodiment of this invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 1, and Fig. 4 is a sectional view taken along the - line in Fig. 1. FIG. In the figure, 1 is a printed circuit board, 2 is an electronic component, 3 is a lead wire, 4 is a chip component, 5 is a solder bath, 6 is a solder bath body, 7 is a solder melt, 7a is an overflow surface,
7b is a jet wave, 8 is a flow dip tank, 9 is an outlet, 10 is a jet tank, 11 is a jet port, and 12 is a rotating plate.

Claims (1)

[Scope of utility model registration request] The solder tank is provided with a solder tank main body containing a solder melt, and a flow dip tank is provided in which the solder melt flows out from an outlet formed at one end and overflows into the solder tank main body to form an overflow surface. A jet tank provided in the main body and provided with a jet port for generating a large number of jet waves on the overflow surface formed in the flow dip tank is provided adjacent to the flow dip tank, and further, the jet tank is provided adjacent to the flow dip tank; A rotary plate is rotatably provided at the outflow port and is rotated by a difference between the outflow force of the solder melt flowing out from the jet tank and the jetting force of the solder melt jetted out from the jet port of the jet tank. A soldering bath characterized by: