JP2000294918A - Blow nozzle, reflow soldering apparatus and reflow soldering method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflow soldering apparatus which can be miniaturized at a low cost. SOLUTION: In this reflow soldering apparatus, a transfer part 10 for transferring a printed board 60, where electronic components 50 are loaded, a preheating part 20 which raises the printed board 60 and the like to a prescribed temperature in advance, a hot air blow nozzle 30 for jetting hot air and dissolving solder paste and a cold air blow nozzle 40 for jetting cold air and caking solder are arranged. In the hot air blow nozzle 30, hot air introduced from outside is raised to a prescribed temperature by a heater 34 arranged around a lead-in path 33, and is jetted to the printed board 60 installed on the transfer part 10 from a lower end 36 of an inner cylinder part 31, and jetted hot air is discharged to an outer part from the lower end 36 of an outer cylinder part 32. A cold air blow nozzle 40 jets cold air introduced from outside to the printed board 60, which is installed on the transfer part 10 from the lower end 36 of the inner cylinder part 31 and discharges jetted cold air form the lower end 36 of the outer cylinder part 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blow nozzle for blowing hot air or cold air introduced from outside and discharging the blown hot air or cold air to the outside, a reflow soldering device provided with the blow nozzle, and The present invention relates to a reflow soldering method.

[0002]

2. Description of the Related Art In recent years, electronic components of a surface mount device (SMD) have been widely used with the miniaturization of electric products. When mounting an electronic component such as an SMD on a printed circuit board, it is necessary to electrically connect the electronic component to the printed circuit board and mechanically fix the electronic component. As one of the techniques, reflow soldering is known. In this reflow soldering, when various electronic components are mounted on a printed circuit board on which a solder paste (solder paste) is printed in advance, the solder paste on the printed circuit board is melted by passing through a reflow soldering apparatus, The electronic component and the printed circuit board are electrically connected and mechanically fixed.

As shown in FIG. 6, a reflow soldering apparatus 100 includes a transport section 130 for transporting a printed circuit board 120 on which electronic components 110 are mounted, and a reflow furnace 140. This reflow furnace 140
Is composed of a preheating unit 150 provided at a preceding stage in the transport direction of the printed circuit board 120, and a main heating unit 160 following the preheating unit 150. In this reflow furnace 140, the electronic component 110 is preheated at a temperature of about 130 to 170 ° C. in order to reduce a thermal shock applied to the electronic component 110, and the melting temperature of the solder paste (about 18
0 [° C.]), about 210 to 230 higher than 30 to 50 ° C.
It is heated at a temperature of [° C]. Then, when the solder is cooled, the solder solidifies and the electronic component 1 is placed on the printed circuit board 120.
10 is securely mounted.

[0004]

By the way, in the preheating section 150 in the reflow furnace 140, the hot air introduced from the outside and the heater 170 provided in the preheating section 150 cause the heat to be convected by heat, so that the electronic components 110 are heated. And printed circuit board 12
Preheating is added to zero. Further, in the main heating section 160 in the reflow furnace 140, the solder paste is melted by hot air introduced from the outside or by a heat convection in the heater 170 disposed in the main heating section 160. For this reason,
In order to reliably mount the electronic component 110 on the printed circuit board 120, it is necessary to maintain the preheating unit 150 and the main heating unit 160 in the reflow furnace 140 at the predetermined temperature.
Therefore, the cost required to maintain the preheating unit 150 and the main heating unit 160 in the reflow furnace 140 at the predetermined temperature tends to increase. In addition, in order to melt the solder paste by thermal convection, it is necessary to increase the size of the reflow furnace 140 to facilitate thermal convection. Therefore, the size of the reflow soldering apparatus 100 also tends to be large.

The present invention has been made in view of such a problem, and has the following objects [1] to [3]. [1] An object of the present invention is to provide a blow nozzle that can contribute to a reflow soldering device.

[2] An object of the present invention is to provide a reflow soldering apparatus which can be reduced in size at low cost. [3] An object of the present invention is to provide a reflow soldering method capable of easily performing reflow soldering.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, hot air or cold air is provided from a lower end of an inner cylindrical portion while being provided in a reflow soldering apparatus. The discharged hot air or cold air is discharged from the lower end of the outer cylinder to the outside.

Therefore, according to the first aspect of the present invention,
Hot air or cold air is blown from the lower end of the inner cylinder. The hot or cold air that has been blown out is discharged to the outside from the lower end of the outer cylinder.

According to the second aspect of the present invention, a rectifying means for rectifying hot air or cold air is provided inside the inner cylindrical portion. Therefore, according to the second aspect of the present invention, the rectified hot air or cold air is blown out from the lower end of the inner cylindrical portion by the rectifying means.

According to a third aspect of the present invention, there is provided a transfer means for transferring a printed circuit board on which a solder paste is printed and on which an electronic component is mounted, a preheating means for raising the printed board and the electronic component to a predetermined temperature, In a reflow soldering apparatus provided with a heating means for melting a solder paste, the heating means is the blow nozzle according to claim 1 or 2, which blows out hot air.

Therefore, according to the third aspect of the present invention,
The printed circuit board and the electronic components conveyed by the conveying means are heated to a predetermined temperature by the preheating means,
The solder paste is melted by the heating means of the blow nozzle according to claim 1 or 2.

According to the present invention, a transfer means for transferring a printed circuit board on which an electronic component is mounted on which a solder paste is printed, a preheating means for raising the printed circuit board and the electronic component to a predetermined temperature, In a reflow soldering apparatus having a heating means for melting a solder paste, a cooling means for solidifying the molten solder is provided.

Therefore, according to the invention described in claim 4,
The solder melted by the heating means is solidified by the cooling means. According to a fifth aspect of the present invention, in the reflow soldering method comprising a preheating step of raising the printed circuit board and the electronic component to a predetermined temperature and a heating step of melting the solder paste, the heating step includes blowing hot air. Then, the solder paste is melted.

Therefore, according to the fifth aspect of the present invention,
The hot air in the heating step melts the solder paste.
According to a sixth aspect of the present invention, in the reflow soldering method comprising a preheating step of raising a printed board and an electronic component to a predetermined temperature and a heating step of melting a solder paste, the solder melted in the heating step And a cooling step for solidifying.

Therefore, according to the invention described in claim 6,
The solder melted in the heating step is solidified in the cooling step. In the embodiments of the invention described below,
The “rectifying means” described in the claims or the means for solving the problem corresponds to the rectifying plate 37, the “transporting means” corresponds to the transport unit 10, and the “preheating means” also corresponds to the preheating unit 20. Similarly, “heating means” corresponds to the hot air blow nozzle 30, and “cooling means” also corresponds to the cool air blow nozzle 40.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the reflow soldering device 1 includes a transport unit 10, a preheating unit 20, a hot air blow nozzle 30, and a cool air blow nozzle 40.

The transport section 10 includes a pair of rollers 11, a pair of endless track belts 12 mounted between the pair of rollers 11, and a motor 13 connected to one of the rollers 11. Note that the other roller 11 is rotatably supported by a shaft. A printed circuit board 60 on which the electronic component 50 is mounted is placed between the pair of belts 12. Then, when the pair of belts 12 is rotated in the direction of the arrow with the rotation of the motor 13, the printed circuit board 60 on which the electronic components 50 are mounted is moved while being placed between the pair of belts 12. .

The preheating section 20 includes a pair of heaters 21 disposed at a position facing the printed circuit board 60 placed between the pair of belts 12, and a preheating furnace 22 that covers the pair of heaters 21. ing. A discharge path 23 for discharging heat in the preheating furnace 22 is provided above the preheating furnace 22.

The hot air blow nozzle 30 blows out hot air introduced from the outside onto the printed circuit board 60 placed between the pair of belts 12, and discharges the blown out hot air to the outside.

The cool air blow nozzle 40 blows cool air introduced from the outside onto the printed circuit board 60 placed between the pair of belts 12, and discharges the blown cool air to the outside.

Next, the configuration of the hot air blow nozzle 30 and the cool air blow nozzle 40 will be described with reference to the drawings.
As shown in FIGS. 2 and 3, the hot air blow nozzle 30
It comprises a substantially rectangular inner cylindrical portion 31 for discharging hot air and a substantially rectangular outer cylindrical portion 32 for discharging the discharged hot air. An introduction path 33 for introducing hot air is formed at an upper portion of the inner cylinder portion 31. Around the introduction path 33, a heater 34 for increasing the temperature of the introduced hot air to a predetermined temperature is provided. A discharge path 35 for discharging the jetted hot air to the outside is formed at an upper portion of the outer cylindrical portion 32. The lower ends 36 of the inner cylinder part 31 and the outer cylinder part 32 are open. Inside the inner cylinder portion 31,
A plurality of rectifying plates 37 for rectifying hot air introduced from the outside are provided. The cold air blow nozzle 40
Is different only in that the heater 34 is not provided.

The operation of the hot air blow nozzle 30, the cool air blow nozzle 40, and the reflow soldering apparatus 1 configured as described above will be described. As shown in FIG.
When the printed board 60 is placed between the pair of belts 12 in a state where the electronic component 50 is mounted on the printed board 60 on which the solder paste is printed, the printed board 60 moves toward the preheating unit 20.

In the preheating unit 20, the printed circuit board 60 and the electronic component 50 are moved toward the hot air blow nozzle 30 while being raised to a predetermined temperature by the pair of heaters 21. In the hot-air blow nozzle 30, first, hot air introduced from the outside is supplied to a heater 34 disposed around the introduction path 33.
To a predetermined temperature. When the raised hot air is ejected from the lower end 36 of the inner tube portion 31 of the hot air blow nozzle, the solder paste printed on the printed circuit board 60 moves toward the cool air blow nozzle 40 while being melted. Then, the jetted hot air is sucked from the lower end 36 of the outer cylindrical portion 32 and discharged to the outside.

Subsequently, the inner cylindrical portion 3 of the cool air blow nozzle 40
The molten solder paste moves while being solidified by the cool air blown out from the lower end 36 of the first solder. At this time, the jetted cool air is sucked from the lower end 36 of the outer cylindrical portion 32 and discharged to the outside. Then, when the solder paste is solidified, the electronic component 50 is securely mounted on the printed board 60.

As described above, according to the present embodiment, the following operations and effects can be obtained. (1) Hot air and cold air are blown by hot air and cold air blow nozzle 3
It is introduced from the upper part of 0, 40 and is ejected from the lower end 36 of the inner cylinder part 31. Then, the hot air and the cool air that have been blown out are sucked from the lower end 36 of the outer cylindrical portion 32 and discharged to the outside.
At this time, the printed circuit board 60 and the electronic component 50 pass below the hot air blow nozzle 30 and then pass below the cool air blow nozzle 40. At this time, after the solder paste is melted, the solder is solidified. Therefore, the printed circuit board 60
And the electronic component 50, the hot and cold air blow nozzles 30,
The electronic component 50 can be reliably mounted on the printed circuit board 60 only by passing under the portion 40. Therefore, the hot and cold air blow nozzles 30 and 40 can contribute to the reflow soldering device 1.

(2) A plurality of rectifying plates 37 for rectifying hot air or cold air are provided inside the inner cylindrical portion 31. For this reason, hot air or cold air introduced from the outside is rectified and ejected to the printed circuit board 60 and the electronic component 50. As a result, the solder paste is uniformly melted and solidified. Therefore, the electronic component 50 can be more reliably mounted on the printed circuit board 60. Therefore, the hot and cold air blow nozzles 30 and 40 can contribute to the reflow soldering device 1.

(3) In addition, the molten solder is quickly solidified by the cool air from the cool air blow nozzle 40.
In other words, the molten solder is solidified by forced cold air. Therefore, the electronic component 50 is quickly and reliably mounted on the printed circuit board 60. Therefore, it is possible to quickly shift to the subsequent cleaning step. Further, even in the case of no cleaning, it is possible to quickly shift to the next step.

(4) After the printed circuit board 60 and the electronic component 50 have passed through the preheating unit 20, they first pass under the outer cylindrical portion 32 of the hot air blow nozzle 30 for discharging the hot air that has been jetted out, and thereafter. It passes below the inner cylinder 31 of the hot air blow nozzle 30 that blows out hot air. For this reason, the printed circuit board 6
After the temperature of the electronic component 50 is raised to a predetermined temperature in the preheating unit 20, the temperature does not rise rapidly. Therefore, it is possible to prevent the electronic component 50 from being broken due to the temperature change.

(5) The hot air and the cold air are supplied from the inner cylinder 31 of the hot and cold air blow nozzles 30 and 40 to the printed circuit board 60.
And the electronic component 50. For this reason, the temperature of hot air and cold air is prevented from being changed by the outside air temperature around the hot air and cold air blow nozzles 30 and 40. Therefore, it is possible to prevent the introduced hot air and cool air from being affected by the outside air temperature around the hot air and cool air blow nozzles 30 and 40.

(6) Hot and cold air blow nozzles 30 and 40 for introducing hot and cold air from the outside are provided to realize melting and solidification of the solder paste. Therefore, there is no need to provide a thermal convection type reflow furnace as in the related art. Therefore, the reflow soldering device 1 can be reduced in size at low cost.

(7) After the hot air is blown from the hot air blow nozzle 30, the cool air is blown from the cool air blow nozzle 40. Therefore, after the solder paste is melted by hot air, the solder is solidified by cold air. Therefore, the reflow soldering method can easily perform the reflow soldering.

(8) A heater 34 for raising the hot air to a predetermined temperature is provided around the introduction path 33 in the hot air blow nozzle 30. For this reason, the hot air introduced from the outside can be reliably raised to the predetermined temperature. Therefore, the solder paste can be reliably melted. Therefore, the electronic component 50 can be reliably mounted on the printed circuit board 60.

The present embodiment can be embodied with the following modifications. -The hot and cold air introduced from outside may be nitrogen gas. Further, an inert gas may be used. With this configuration, when the solder paste is melted and solidified, it can be prevented from being oxidized.

Further, only hot air may be nitrogen gas or inert gas. According to this structure, when the solder paste is melted, it can be prevented from being oxidized. A configuration may be adopted in which normal-temperature air is introduced from the outside and heated by a heater 34 disposed around the introduction path 33.

Hot and cold air blow nozzles 30 and 40
May be configured to be changed according to the size of the printed circuit board 60.・ Lower end 3 of hot and cold air blow nozzles 30 and 40
6 may be configured to be changeable.

Hot and cold air blow nozzles 30, 40
May have a cylindrical shape, a polygonal shape, or the like. -As shown in Fig. 4A, the current plate 37 is formed of the outer cylindrical portion 32.
It may be a straightening plate extended up to this point.

As shown in FIG. 4B, the current plate 37
May be a rectifying plate 37 parallel to the transport direction of the printed circuit board 60. As shown in FIG. 4C, a rectifying plate 37 that is parallel to the transport direction and a rectifying plate 37 that is parallel to the transport direction (lattice-shaped rectifying plate 37) may be used.

As shown in FIG. 5, the upper end of the current plate 37 may be tapered. With this configuration, hot air and cold air can be uniformly blown from the lower ends 36 of the hot air and cold air blow nozzles 30 and 40.

Without disposing the cool air blow nozzle 40,
A configuration in which the solder is solidified by natural cooling may be adopted. With this configuration, the size of the reflow soldering device 1 can be further reduced.

Reflow in a mounting apparatus including a printing apparatus for printing solder paste on a printed circuit board 60, a mounting apparatus for mounting the electronic component 50 on the printed circuit board 60 on which the solder paste is printed, and the reflow soldering apparatus 1. You may apply to the soldering apparatus 1.

Further, technical ideas other than the claims grasped from the above embodiment will be described below together with their effects. [1] In the blow nozzle according to claim 1 or 2, a temperature increasing means for increasing the hot air to a predetermined temperature is provided around the introduction path in the inner cylindrical portion for introducing the hot air from the outside. Blow nozzle.

With this configuration, the hot air introduced from the outside can be reliably raised to a predetermined temperature, and the electronic components can be reliably mounted on the printed circuit board. [2] The blow nozzle according to [2] or [1], wherein the rectifying means includes a plurality of rectifying plates.

With this configuration, the hot and cold air introduced from the outside can be further rectified. [3] A reflow device according to claim 3 or 4, wherein the mounting device includes a printing device for printing solder paste on a printed circuit board and a mounting device for mounting electronic components on the printed circuit board on which solder paste is printed. A mounting device equipped with a soldering device.

With this configuration, the mounting apparatus can be reduced in size at low cost.

[0045]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the present invention, it is possible to contribute to a reflow soldering device.

According to the invention described in claim 2, according to claim 1
In addition to the effects described in (1), since the hot air or the cool air is rectified, the electronic components can be reliably mounted on the printed circuit board.

According to the third aspect of the invention, the reflow soldering apparatus can be reduced in size at low cost. According to the invention described in claim 4 or claim 6, it is possible to quickly shift to the next step.

According to the invention described in claim 5, reflow soldering can be easily performed.

[Brief description of the drawings]

FIG. 1 is a front view showing a reflow soldering device according to an embodiment.

FIG. 2 is a perspective view showing hot air and cold air blow nozzles.

FIG. 3A is a cross-sectional view illustrating a hot air and a cold air blow nozzle. (B) A bottom view showing the hot air and cold air blow nozzles.

FIGS. 4A to 4C are bottom views showing hot air and cold air blow nozzles according to another embodiment.

FIG. 5 is a sectional view showing a current plate in another embodiment.

FIG. 6 is a front view showing a conventional reflow soldering device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Reflow soldering apparatus, 10 ... Conveying part as a conveying means, 20 ... Preheating part as a preheating means, 30 ... Hot air blow nozzle as a heating means, 37 ... Rectifying plate as a rectifying means, 40 ... Cooling means Cold air blow nozzle,
50: electronic parts, 60: printed circuit board.

Claims (6)

[Claims] 1. A reflow soldering device, comprising:
Hot air or cold air is blown out from the lower end of the inner cylinder,
A blow nozzle that discharges hot or cold air blown out from the lower end of the outer cylinder. 2. The blow nozzle according to claim 1, wherein a rectifying means for rectifying hot air or cold air is disposed inside the inner cylindrical portion. 3. A conveying means for conveying a printed circuit board on which an electronic component is mounted with a solder paste printed thereon, a preheating means for raising the printed circuit board and the electronic component to a predetermined temperature, and a heating means for melting the solder paste. The reflow soldering apparatus according to claim 1, wherein the heating unit blows out hot air. 4. 4. A transport means for transporting a printed board on which an electronic component is mounted with a solder paste printed thereon, a preheating means for raising the printed board and the electronic component to a predetermined temperature, and a heating means for melting the solder paste. A reflow soldering apparatus comprising: a reflow soldering apparatus having cooling means for solidifying molten solder. 5. A reflow soldering method comprising: a preheating step of raising a printed board and an electronic component to a predetermined temperature; and a heating step of melting a solder paste, wherein the heating step includes blowing hot air to remove the solder paste. Reflow soldering method to melt. 6. A reflow soldering method comprising: a preheating step of raising a printed board and an electronic component to a predetermined temperature; and a heating step of melting a solder paste, wherein a cooling step of solidifying the solder melted in the heating step. A reflow soldering method also having: