JPH0846345A - Soldering device - Google Patents

Abstract

PURPOSE:To provide a soldering device, which can conduct the improvement of the quality of soldering and the manufacture of wiring boards at low running cost, by a method wherein the wiring boards are cooled immediately and efficiently and at the same time, an unwanted flow of the atmosphere in a chamber is prevented. CONSTITUTION:In order to solder wiring boards 1 within a chamber 2 while the wiring boards 1 are transferred, a first transfer conveyor 3 having an angle theta1, of elevation and a second transfer conveyor 4 having an angle theta2, of depression are provided, inhibition plates 13 for inhibiting the flow of an atmosphere in the chamber 2 are provided and cooling pipes 44, through which cooling water 45 is made to pass, for cooling the boards 1 subsequent to the end of the soldering are respectively arranged in order between the plates 13 being provided on the part, which is located on the side of a carrying-out port 6, of the chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering apparatus for soldering in a low oxygen concentration atmosphere covered with a chamber.

[0002]

2. Description of the Related Art The soldering process can be roughly divided into a flow soldering process and a reflow soldering process. Then, in order to realize cleaning-free and micro-soldering of the wiring board after soldering, an inert gas of low oxygen concentration (for example, nitrogen gas: N ₂ )
There are many examples of performing these soldering processes in an atmosphere. On the other hand, forming an atmosphere with a lower oxygen concentration with a smaller nitrogen gas consumption is an essential requirement for suppressing the running cost of the soldering device to a low level.

FIG. 4 is a side sectional view showing an example of a conventional soldering apparatus, a part of which is shown in a block diagram.

In the figure, reference numeral 1 is a wiring board, 2 is a tunnel-shaped chamber, and as means for carrying the wiring board 1 in the carrying direction A (direction of arrow A) in the chamber 2, for example, from a carrying chain. Becomes the first conveyor 3
And a second conveyor 4 made up of a belt. Reference numeral 5 is a carry-in port of the wiring substrate 1, 6 is a carry-out port, 7 is a preheater for preheating the wiring substrate 1, 8 is a solder bath for soldering the wiring substrate 1, and a solder melt 9
The jet wave 12 is jetted from the nozzle 10 by driving a pump mechanism (illustrated by blades in FIG. 4) 11.

In the chamber 2 and the carrying means, in the preheating process part by the preheater 7 and the flow soldering process part by the solder bath 8, the carrying direction A of the wiring substrate 1 is used.
It has an elevation angle θ ₁ that rises with respect to the vertical direction and a depression angle θ ₂ that descends with respect to the transport direction A of the wiring board 1 after the soldering process is completed. Therefore, when the soldering apparatus is viewed from the side, the chamber 2 has a "V" shape. Further, the transport means is also composed of a first transport conveyor 3 having an elevation angle θ ₁ and a second transport conveyor 4 having a depression angle θ ₂ .

Further, in the chamber 2, plate-shaped members whose plate surfaces are oriented in a direction intersecting the transporting direction A of the wiring board 1 are sequentially arranged in the transporting direction A, whereby a so-called labyrinth flow path is provided. To prevent unnecessary flow of the atmosphere in the chamber 2. Therefore, this plate-shaped member is called the inhibition plate 13. The unnecessary flow is, for example, heat convection, and is the operation of the transfer conveyors 3 and 4 and the removal of the atmosphere in the chamber 2 accompanying the transfer of the wiring board 1.

Further, in the chamber 2, an N ₂ gas injection nozzle 24 having a jetting directivity is provided on the front side of the solder bath 8, that is, on the jet wave 12 side of the solder bath 8 after the soldering process is completed, From N ₂ gas supply device 21 to N ₂
The gas 25 is supplied. As a result, the carry-out of the N ₂ gas 25, which is the atmosphere in the chamber 2 due to the operation of the first transfer conveyor 3 and the transfer of the wiring board 1, is suppressed,
It becomes possible to suppress and balance the atmospheric flow. In addition, 22 shows a piping part and 23 shows a control valve.

An air supply nozzle 34 is provided at the carry-out port 6 of the chamber 2, and an air curtain is formed by the air 35 supplied from the air supply device 31. Thereby, the sealing property at the opening of the chamber 2 (the carry-out port 6 and the carry-in port 5) is enhanced. In addition, 32 shows a piping part and 33 shows a control valve.

As described above, in the conventional soldering apparatus, the wiring board 1 is cooled by the chamber 2 after the soldering.
In many cases, a cooling air is blown outside the room by a fan or the like (not shown). The reason why the wiring board 1 is cooled outside the chamber 2 is to suppress the atmospheric flow of the N ₂ gas 25 in the chamber 2. That is, this is to keep the oxygen concentration in the chamber 2 stable.

As described above, in the chamber 2, the flow of the atmosphere by the N ₂ gas 25 is suppressed, the sealing property with the outside air is enhanced, and the atmosphere of low oxygen concentration is set in the chamber 2.
Formed within.

The second transfer conveyor 4 may be a transfer chain, and the first transfer conveyor 3 and the second transfer conveyor 4 are not divided but are one continuous transfer chain. It may be formed in the shape of "he".

Next, the operation will be described.

The wiring board 1 carried in from the carry-in port 5 and held on the first carrying conveyor 3 is carried at an elevation angle θ ₁ , preheated by the preheater 7 in an atmosphere of low oxygen concentration, and jetted in the solder bath 8. The waves 12 are contacted for soldering. Subsequently, the wiring board 1 held by the second conveyor 4 is conveyed at a depression angle θ ₂ and is conveyed from the outlet 6.

[0014]

By the way, it is desirable to immediately cool the wiring board 1 soldered in the soldering step. That is, the mechanical strength of soldering is increased so that cracks or the like do not occur due to rocking or the like that occurs during the transportation process. Also, heat shock of electronic components (not shown) mounted on the wiring board 1 is suppressed.
This is to alleviate. Furthermore, it is because the warp due to the thermal expansion of the wiring board 1 can be easily repaired.

However, the conventional soldering device shown in FIG. 4 has a problem in that it is not provided with a cooling device for cooling immediately after soldering.

Incidentally, Japanese Utility Model Laid-Open No. 5-262 discloses that
A technique of providing a cooling chamber equipped with a heat exchanger in a reflow device is disclosed, but since the volume of the cooling chamber is about the same as that of the reflow chamber, it takes time to cool the cooling chamber. However, since a separate cooling chamber is required, the soldering device becomes larger than the conventionally used device.

The present invention is to enable the wiring board soldered in the soldering process to be immediately cooled while suppressing unnecessary flow of the atmosphere in the chamber, and also without increasing the size of the soldering apparatus. An object of the present invention is to provide a soldering apparatus that enables efficient production of a wiring board having high soldering quality and reliability at a low running cost.

[0018]

The present invention is characterized in that a cooling pipe through which a cooling medium such as cooling water is passed is arranged between the restraining plates.

Therefore, according to the first aspect of the present invention, the wiring board is provided between the respective restraining plates in the front portion of the soldering process part with respect to the direction in which the wiring board is transported. Cooling pipes for passing a cooling medium for cooling are sequentially arranged in parallel.

According to a second aspect of the present invention, in the tunnel chamber and the conveyor, the preheating step and the soldering step are formed at an elevation angle with respect to the direction of conveyance of the wiring board, and the preheating step and The portion after the soldering process is formed to have a depression angle, and the cooling pipes are sequentially arranged in parallel in the chamber having the depression angle.

[0021]

According to the first aspect of the present invention, the soldered wiring board can be immediately cooled by the cooling pipe through which the cooling medium is passed. Further, since the cooling pipes through which the cooling medium is passed are arranged between the respective restraining plates, unnecessary flow does not occur in the atmosphere in the chamber due to the cooling.

Further, since the atmosphere in the chamber cooled by the cooling pipe is surrounded by the inhibition plate, the cooling atmosphere can be fixed and heat exchange with the wiring board can be performed without waste.

Further, since the cooling pipe is arranged on the carry-out side of the chamber after the soldering process is completed,
It is possible to reduce the temperature difference between the atmospheric temperature inside the chamber and the atmospheric temperature outside the chamber in the vicinity of the carry-out port, and it is difficult for thermal convection to occur in the region inside and outside the chamber due to this temperature difference. That is, the sealing property is improved.

Further, according to the second aspect of the invention, the wiring board to which the soldering has been applied can be immediately cooled, and unnecessary flow does not occur in the atmosphere. Further, heat exchange can be performed without waste, and the wiring board can be cooled efficiently.

By the way, since an atmosphere having a high temperature and a low density is accumulated in a high portion of the chamber, it is known that the chamber having a portion having an elevation angle and a portion having a depression angle has a good atmosphere sealing property. ing. That is, this structure can significantly suppress the heat convection and the carry-out of the atmosphere.

In the vicinity of the outlet of the chamber having a depression angle, the temperature difference between the atmospheric temperature inside the chamber and the atmospheric temperature outside the chamber can be further reduced by the cooling pipe, so that the sealing performance is further improved. .

[0027]

Next, a soldering apparatus according to the present invention will be described.

FIG. 1 is a side sectional view showing an embodiment of the present invention,
2 is a partially cutaway perspective view showing in an enlarged manner a mode in which a cooling pipe is arranged in the chamber of FIG. 1, and FIG. 3 is a bottom view showing the connection of the cooling pipe of FIG. In these figures, the same reference numerals as those in FIG. 4 indicate the same parts, 41 is a cooling water supply device, 42 is a piping part, 43 is a control valve, and 44 is a cooling pipe. In addition, in FIGS. 1 to 3, reference numeral 45 indicates the cooling water or the flow direction thereof by an arrow. Furthermore, FIG.
In 47, a coupler 47 connects the cooling pipe 44 with the connecting pipe 46. Reference numeral 36 is a coupler for connecting the air ejection nozzle 34 to the pipe portion 32.

That is, in the portion of the chamber 2 having the depression angle θ ₂ of the soldering device, the cooling pipes 44 are arranged in parallel between the restraining plates 13, and the cooling pipes 44 are connected in series via the coupler 47 and the connecting pipe 46. This is an example in which the cooling water supply device 41 supplies the cooling water 45 and the cooling water supply device 41 sequentially flows through the cooling pipes 44. Although the cooling water 45 may be disposable, it may be circulated and reused by being returned and radiated to the cooling water supply device 41.

As for the order of passing the cooling water 45 through the cooling pipe 44, in the example of FIG. 1, the cooling water 45 is configured so as to flow sequentially from the side close to the solder bath 8 to the carry-out port 6 side, and soldering is performed. Although it is considered that the performed wiring board 1 can be rapidly and immediately cooled, cooling water 45 may be passed in the opposite direction so that the wiring board 1 can be gradually cooled. This is
This is because it is considered that the cooling water 45 receives heat energy from the atmosphere in the chamber 2 in the process of flowing the cooling pipe 44 to raise the water temperature. That is, the cooling water 45 flowing through the cooling pipes 44 is
The temperature rises gradually in the process of flowing. Therefore, if it is desired to maintain a uniform water temperature, it suffices to connect the cooling pipes 44 in parallel to pass water. It is also effective to control the water temperature of the cooling water 45 so that the desired cooling temperature is obtained.

In addition, providing fins (not shown) on the cooling pipe 44 to increase the surface area and improve the cooling performance can be easily carried out by a known technique.

Next, the operation will be described.

The soldering process of the wiring board 1 is the same as that of the conventional example shown in FIG. 4, but when the wiring board 1 held by the second conveyor 4 is conveyed at the depression angle θ ₂ , the cooling pipe 44 is attached. Heat is dissipated and cooled when passing through the portion where it is arranged.
Then, it is carried out from the carry-out port 6.

Since the cooling pipes 44 are arranged between the respective restraining plates 13, the cooled atmosphere is different from that of the respective restraining plates 1.
It is held between 3 and has a good cooling property for the wiring board 1. Therefore, unnecessary atmosphere flow does not occur with cooling. Further, the cooling water 45 is adjusted so that the atmospheric temperature in the chamber 2 on the side of the carry-out port 6 becomes approximately equal to the atmospheric temperature.
If the temperature is adjusted, heat convection does not occur through the carry-out port 6, and therefore the atmosphere sealing property is significantly improved. The temperature of the cooling water 45 can be adjusted by a known technique such as a heat pump or a heater.

Although the flow soldering apparatus has been described as an example in the above embodiments, the present invention can of course be used in a reflow soldering apparatus. That is, a labyrinth passage is formed in the chamber 2 by forming a labyrinth flow path in the portion on the carry-in port 5 side before preheating in the preheating process part and the part on the carry-out port 6 side after soldering is completed in the reflow soldering process part. It is generally performed to improve the sealing property. For example, examples thereof can be found in "Reflow furnace" disclosed in Japanese Utility Model Laid-Open No. 4-98364 and "Heating furnace for soldering" disclosed in Japanese Patent Laid-Open No. 5-305429.

Therefore, on the unloading port 6 side after the reflow soldering process is completed, between the plate-like members forming the labyrinth flow paths, that is, the respective restraint plates 13 and 13,
The cooling pipes 44 may be sequentially arranged in parallel.

As a result, the reflow soldered wiring board 1 is immediately cooled, the reflow soldering apparatus does not become large, and the atmosphere sealing property is improved.

[0038]

As described above, according to the invention of claim 1 of the present invention, between the respective restraining plates and the restraining plates in the front side portion of the soldering process part with respect to the direction in which the wiring board is conveyed, Since the cooling pipes for passing the cooling medium for cooling the wiring board are sequentially arranged in parallel, the wiring board can be immediately cooled, and the cooling atmosphere can be fixed so that the wiring board can be cooled without waste. . Further, as the wiring board is cooled, unnecessary flow does not occur in the atmosphere inside the chamber, and the temperature difference between the ambient temperature and the outside air in the vicinity of the outlet of the chamber can be reduced, so there is no heat convection and the atmosphere is sealed. And the soldering apparatus is not increased in size.

According to a second aspect of the present invention, in the tunnel chamber and the transfer conveyor, the preheating step and the soldering step are formed at an elevation angle with respect to the transfer direction of the wiring board, and preheating and soldering are performed. Since the portion after finishing the soldering is formed in the depression angle, and the cooling pipes are sequentially arranged in parallel in the chamber having the depression angle, it is possible to immediately cool the wiring board soldered in the soldering process. . In addition, unnecessary flow of the atmosphere in the chamber can be suppressed even better. Moreover, these can be efficiently performed without increasing the size of the conventional soldering apparatus.

As a result, there is an advantage that a wiring board having high soldering quality and high reliability can be manufactured at low running cost.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view showing in an enlarged manner a mode in which a cooling pipe is arranged in the chamber of FIG.

FIG. 3 is a bottom view showing the connection of the cooling pipes of FIG.

FIG. 4 is a side sectional view showing an example of a conventional soldering device.

[Explanation of symbols]

 1 Wiring Substrate 2 Chamber 3 First Conveyor 4 Second Conveyor 5 Carrying In 6 Carrying Out 7 Preheater 8 Solder Tank 9 Solder Melt 10 Nozzle 12 Jet Wave 13 Suppression Plate 41 Cooling Water Supply Device 42 Piping 43 Valve 44 Cooling pipe 45 Cooling water 46 Connection pipe 47 Coupler

Claims (2)

[Claims] 1. A transport conveyor for transporting a wiring board, a preheating step section for preheating the wiring board, and a flow soldering step section or a reflow soldering step section for soldering in a tunnel-shaped chamber. And a restraining plate having a plate surface oriented in a direction intersecting the transporting direction of the wiring board is sequentially arranged in the chamber along the transporting direction of the wiring board. For cooling through a cooling medium that cools the wiring board, between the respective restraining plates and the restraining plate in the front side portion of the flow soldering process section or the reflow soldering process section with respect to the direction in which the wiring board is transported. A soldering device characterized in that pipes are sequentially arranged side by side. 2. The tunnel-shaped chamber and the conveyor are formed after the preheating step and the soldering step are completed with the preheating step and the soldering step being formed at an elevation angle with respect to the direction in which the wiring board is conveyed. The soldering apparatus according to claim 1, wherein the cooling pipes are formed in a depression angle, and the cooling pipes are sequentially arranged side by side in the chamber having the depression angle.