JPH05146869A - Nitrogen-sealed type soldering device - Google Patents

Abstract

PURPOSE:To provide the soldering device where a necessary nitrogen atmosphere at the soldering stage can be always maintained even when the carrying width is changed in the nitrogen-sealed type soldering device having a carrierless carrying mechanism with the variable carrying width where at least the soldering stage is carried out in the necessary nitrogen atmosphere. CONSTITUTION:In the nitrogen-sealed type soldering device provided with a carrier conveyor 2 with the variable carrying width and a solder vessel below it, a shielding body 19 to form shielding space including the carrier conveyor 2 is provided above the solder vessel. This shielding body 19 is constituted of a surrounding body 16 which surrounds the carrier conveyor 2 (tracks 2a and 2b) and forms tunnellike space and a shutter 30 to blockade an opening of this surrounding body 16 and the shutter 30 is provided with blockage width adjusting means 32, 34, etc., to follow the width change of the tracks 2a and 2b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nitrogen-filled type soldering apparatus, and more particularly to a soldering apparatus having a pair of parallel tracks whose distances from each other can be adjusted, and at least at the upper part of the solder tank. , A nitrogen-filled type soldering device comprising a shield for forming a shielded space including the transfer conveyor.

[0002]

2. Description of the Related Art Conventionally, in a soldering process, a flux is usually applied in advance to a portion to be soldered of a product to be soldered. The flux melts at a temperature lower than the melting point of solder and reacts with metal oxides to form slag, which acts to shield the molten metal from air and prevent its oxidation. As the flux, a flux containing pine resin (rosin) or a halide is generally used. By the way, if this flux remains on a soldered product such as a printed circuit board, it may cause corrosion or decrease in insulation resistance. Therefore, conventionally, cleaning with chlorofluorocarbon or trichloroethane was performed after the soldering process. However, in recent years, these CFCs,
It has been decided that trichloroethane will be internationally regulated as an ozone depleting substance.

Under such circumstances, recently, a soldering apparatus which does not require cleaning of flux in a soldering process of a printed circuit board has begun to be provided. It was developed from the following viewpoints. In other words, the flux is a so-called reducing agent (antioxidant), and the stronger the action, the better the original function of the flux is. However, such flux has a large amount of residue, which requires cleaning after soldering. .. In other words, the soldering apparatus described above uses a flux having a small reducing action to volatilize the flux in the soldering process, thus eliminating the need for cleaning the flux. When such a flux is used, it is feared that the terminals and copper foil will be oxidized before reaching the soldering part, so soldering should be performed in an inert gas (nitrogen gas) atmosphere. There is.

For example, ELECTRONIC PACKING & PRODUCTIO
N magazine, April 1990 issue, P64-P66, from fluxer to preheater in jet type soldering equipment,
The entire transfer system to the solder tank and the cooling device is covered with a cover (shield) in a tunnel shape, and a nitrogen gas supply port is arranged almost inside the cover. An enclosed jet soldering device is disclosed. In this case, the oxygen concentration inside the cover that covers the entire transport system is about 50 ppm or less.
According to the nitrogen-filled type soldering apparatus as described above, good soldering can be performed even if a flux having a small reducing action is used.

[0005]

However, the above-mentioned nitrogen-filled soldering device has the following disadvantages. That is, in the above apparatus, the transport mechanism for transporting the printed circuit board is of the carrier type (pallet transport type). Therefore, the transport path is formed in a so-called belt conveyor shape having a fixed width, and the printed circuit boards are mounted one by one on a dedicated pallet and transported on the transport belt. Due to such a structure, the above-mentioned nitrogen-filled type soldering device is a carrierless type, that is, a soldering object such as a printed circuit board is directly held on the transport conveyor 2 and transported, and the trajectory of the transport conveyor 2 It cannot be applied to a soldering device having a variable width.

Further, the inventors of the present invention have now confirmed that in the nitrogen-filled jet-type soldering apparatus as described above, the soldering tank can be used for soldering without carrying out a nitrogen atmosphere in the entire conveying system corresponding to each process. It has been found that soldering can be performed satisfactorily if only the corresponding portion can be formed in the required nitrogen atmosphere.

The present invention has been made in view of the above circumstances, and has carrierless conveying means with a variable conveying width, and
To provide a nitrogen-filled type soldering device capable of reliably creating a nitrogen atmosphere in a soldering process part in a nitrogen-filled type soldering device in which at least a soldering process is performed in a required nitrogen atmosphere. To aim.

[0008]

The invention according to claim 1 is
It has a pair of parallel tracks whose distances from each other can be adjusted, and a solder tank is placed below a conveyor that conveys the products to be soldered, so that at least the soldering process is performed in a nitrogen atmosphere. A nitrogen-encapsulated soldering device comprising a shield for forming a shielded space including the transfer conveyor above the solder bath, wherein the shield includes at least the both tracks above the solder bath. A surrounding body that forms a tunnel-shaped space extending in the extending direction of the track, and a shutter that closes the opening of the tunnel-shaped space formed by the surrounding body at least between the two tracks, Further, the shutter has a closing width adjusting means for following the width change of the track.

According to a second aspect of the present invention, in the nitrogen-filled soldering apparatus according to the first aspect, the shutter is supported at an upper end portion thereof and is movable in the width direction, and adjacent ones are mutually adjacent. It is characterized in that a plurality of strip-shaped shielding members that can be overlapped are connected in series, and that the shielding members are formed of a material having high flexibility.

[0010]

In the nitrogen-filled soldering apparatus according to the first aspect of the invention, the shutter provided with the closing width adjusting means closes the opening of the surrounding body even when the track width is changed, thereby creating a nitrogen atmosphere. Space is always maintained.

In the nitrogen-filled soldering apparatus according to the second aspect, the width of the shutter is reduced by overlapping (wrapping) the strip-shaped shielding members that are continuously provided, and the shielding members that are overlapped are spread. By doing so, the width of the shutter is expanded. Further, since the shielding member has flexibility, the soldered article that has been conveyed can pass through the shutter in a form of being pushed away.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a nitrogen-filled soldering device according to the present invention (hereinafter abbreviated as "soldering device") 15
The present invention is applied to a jet-type soldering device for a mounted printed circuit board in the vicinity of the solder bath 8 of FIG.

In these drawings, reference numeral 2 is a conveyer conveyor, and the solder bath 8 is located below the conveyer conveyor 2. In the present embodiment, the solder bath 8 is formed into two baths by a partition plate 13 as shown in FIG. 2, and one bath has a first nozzle 11 and the other bath has a second nozzle 11. Nozzle 12 is provided. The solder bath 8
A nitrogen supply pipe 1 for ejecting nitrogen gas at a position near the upper end of the substrate and below the conveyance line L of the printed circuit board.
4, 14, ... (FIG. 2) are provided. Nitrogen gas generated by a nitrogen generator (not shown) is introduced into these nitrogen supply pipes 14.

Below the transfer conveyor 2, in addition to the solder tank 8, not-shown fluxers, preheaters and the like are located on the front side of the solder tank 8 and a cooling fan is located on the rear side of the solder tank 8 (above the conveyor 2). Are arranged. However, the flux used in the nitrogen-filled soldering apparatus 15 according to the present invention is a special one having a small reducing action, and does not require cleaning after soldering. Further, the fluxer for applying the flux to the soldering surface of the printed circuit board is of a type in which the flux is sprayed and sprayed. In FIG. 1, reference numeral 3 is a transfer claw that moves along each of the tracks 2a and 2b that form the transfer conveyor 2, and as shown in the figure, the printed board P is directly gripped and transferred between the transfer claws 3 facing each other. To do.

A track 2a constituting the transfer conveyor 2,
As shown in FIG. 1, the trajectories 2a, 2a,
2b, or the frames 10 for suspending and supporting the devices such as the fluxer and the pre-heater are the tracks 2a and 2 respectively.
It extends in parallel with the tracks 2a and 2b at substantially the same height as b. That is, the change of the transfer angle of the transfer conveyor 2 is performed by changing the angles of the frames 10, 10.

The distance between the two tracks 2a and 2b, that is, the conveyance width, can be changed and adjusted by a track width adjusting mechanism (not shown).

As shown in FIGS. 1 and 2, in portions of the frames 10 and 10 that substantially correspond to the solder bath 8, a predetermined space is provided to maintain the space above the solder bath 8 in a required nitrogen atmosphere. A shield 19 that forms a shielded space is attached. The shield 19 includes a surrounding body 16 that forms a tunnel-shaped space S extending in the extending direction of the tracks 2a and 2b so as to include the tracks 2a and 2b at least above the solder bath 8. And a shutter 30 that closes the opening of the tunnel-shaped space S formed by the surrounding body 16.

As shown in FIG. 1, the surrounding body 16 has a width between both frames 10, 10 and, as shown in FIG. 2, the solder bath 8 in the extending direction of the frames 10, 10. It is formed to be sufficiently long in the front-rear direction rather than the length. As shown in FIGS. 1 and 2, in this embodiment, the surrounding body 16 includes an upper cover 16A provided above the transport conveyor 2 and a lower cover 16B provided below the transport conveyor 2. It consists of In this embodiment, both the upper cover 16A and the lower cover 16B are formed by bending a stainless plate.

As shown in FIGS. 1 and 2, the upper cover 16A has a rectangular top plate 17 and four side plates 18a, 18b, 18c, 18 bent vertically downward from the four sides of the top plate 17.
and d. Of these side plates 18a to 18d, the two facing side plates 18a and 18c are in the direction orthogonal to the extending direction of the transport conveyor 2 (frame 10), and the other two facing side plates 18b and 18d are in the frame. It is oriented in the direction along the line 10. The upper cover 16A is attached to the frame 10 by fixing the side plates 18b and 18d to the outer surface 10a of the frame 10 with screws, for example. Further, in this case, the top plate 17 of the upper cover 16A is mostly constituted by the transparent glass plate 22 fitted in the locking groove 21, and the solder bath 8 is also provided from above the upper cover 16A. It is configured so that you can look into.

The lower cover 16B has a bottom plate 23 having a size corresponding to the solder bath 8 and covering at least the entire upper opening of the solder bath 8. Both ends of the bottom plate 23 (ends in the left-right direction on the paper surface in FIG. 1) rise upward, and the rising ends are bent outward in the horizontal direction.
4 is forming. The mounting portion 24 is a frame 10,
10 and is attached to the lower surfaces 10b and 10b thereof with, for example, screws.

A portion of the bottom plate 23 corresponding to the solder bath 8 has a rectangular opening 25 as shown in FIG. 3, and the upper surface of the solder bath 8 is exposed from the opening 25. This bottom plate 23, as shown in FIG.
1 and 12 are located below the spouting ports 11a and 12a, and therefore these spouting ports 11a and 12a
Is at a position slightly above the opening 25. However, the bottom plate 23 is located above the upper end of the outer wall of the solder bath 8.

As shown in FIGS. 1 and 2, shield plates 26a, 26b, 26c, and 26d are provided so as to protrude downward from the four sides that are the peripheral portions of the opening 25, respectively. These shield plates 26a to 26d are formed by bending the ones originally located in the opening 25 and are made of stainless steel plates. These shield plates 26a-
The lower part of 26d is inserted inside the solder bath 8, that is, in the molten solder. These shield plates 26a to 26
d is provided in a position close to the inner wall surface side plate of the solder bath 8 in a non-contact state with the inner wall surface.
It is located far outside of 1,12. Of the shield plates 26a to 26d, the pair of shield plates 26b and 26d provided in the extending direction of the conveyor 2 crosses the partition wall plate 13 of the solder bath 8, so that as shown in FIG. 2 or FIG. The portion corresponding to the partition plate 13 has a form in which the partition plate 13 is escaped by the groove 27.

As described above, the upper cover 16A and the lower cover 16B constitute the surrounding body 16 which constitutes the tunnel-shaped space S. However, in the configuration of the present embodiment, the space S is based on the configuration of the lower cover 16A, and in the portion of the solder bath 8, the solder bath 8
The structure is closed by the molten solder surface inside.

The shutter 30 is, as shown in FIG.
Of the side plates 18a to 18d of the upper cover 16A, the side plate 1 formed at the front and rear in the direction orthogonal to the frame 10.
They are provided inside 8a and 18c, respectively. The shutter 30 includes the upper cover 16A and the lower cover 16B.
Between the two tracks 2a and 2b, and between one track 2b and the frame 10 located outside thereof (FIG. 5).

As shown in FIG. 5, the shutter 30 is composed of a plurality of strip-shaped shielding members 31, 31, ... Arranged in the width direction. In this case, these shielding members 31 are made of a flexible film. These shielding members 31 are formed in a groove 33 (FIG. 6) formed between guide rails 32, 32 provided in parallel with the side plates 18a, 18c near the inner upper ends of the side plates 18a, 18c of the upper cover 16A.
To be slidable along the groove 33. As shown in FIG. 6, the upper end of each shielding member 31 is bent to one side to form a bent portion 34, and the bent portion 34 is hooked on the upper surface of one guide rail 32. The shielding members 31 are adjacent to each other.
One is configured so that it can overlap each other.

FIG. 7 shows the structure of the bent portion 34 in detail. In this bent portion 34, an upward hook 35 is provided on the upper surface of one end 34a and a downward hook is provided on the lower surface of the other end 34b. The pawl 36 projects slightly. The upward hooking claws 35 are the downward hooking claws 3 of the adjacent shield member 31.
It is configured to be hooked with 6.

Further, as shown in FIG. 8, each shield member 31 is formed with a projecting piece 37 slightly protruding vertically from the back surface at a side end portion corresponding to the end portion 34b in the back surface width direction. ing. When the shield member 31 moves in the closing direction, the protrusions 37 come into contact with the side portions of the adjacent shield member 31 overlapping the shield member 31 and push the adjacent shield member 31.

Now, the shutter 30 (30A, 30
B) is provided between the two orbits 2a and 2b, and between the orbit 2b and the frame 10 parallel to it, as shown in FIG. Both shutters 30A,
The orbit 2a of each screen 31 constituting 30B
And the screen 31a adjacent to the same track 2a, and the screen 31b and the screen 3 adjacent to the track 2b.
1c is connected to the same track 2b, and the screen 31d adjacent to the frame 10 is connected to the same frame 10.

Next, the operation of the nitrogen-filled type soldering device 15 having the above structure will be described. In this nitrogen-filled soldering device (hereinafter abbreviated as “soldering device”) 15, a shielding space is formed in the space above the solder bath 8.

That is, above the solder bath 8, there are an upper cover 16A and a lower cover 16B, and the tracks 2a, 2b.
The surrounding body 16 that surrounds the above to form a tunnel-like space
Further, since the opening portion of the surrounding body 16 is closed by the shutter 30, a shielded space is formed which substantially surrounds the surroundings.

In the operating state of the soldering device 15, nitrogen gas is jetted from the nitrogen supply pipes 14, 14, .... Since the nitrogen supply pipes 14 are provided near the upper end of the solder bath 8 as described above, the spouted nitrogen gas fills the internal space of the shield 19. As a result, a nitrogen atmosphere having an oxygen concentration of 5% or less is created inside the shield 19 even when a nitrogen generator utilizing membrane separation (for example, not a nitrogen cylinder) is used as the nitrogen generating means as in this embodiment. It is possible to put out. In the present specification, the “nitrogen atmosphere” does not mean a nitrogen gas concentration of 100%, but means a state in which the proportion of nitrogen is higher and the proportion of oxygen is lower than that in normal air.

The printed circuit boards P to be soldered are successively conveyed by the conveyor 2, and first, a flux having a low reducing action is applied to the soldering surface (rear surface) by a spray type fluxer (not shown), and then on the preheater. It passes through and approaches the solder bath 8 and reaches the shield 19. The entrance to the shield 19 is the shutter 30 (3
0A), the shielding member 31 constituting the shutter 30 is made of an extremely flexible film, so that the printed board P (mounting board on which electronic components are mounted) can easily push the shutter 30A away. Can pass through. When the electronic components mounted on the printed circuit board P pass through, the lower ends of the shielding members 31 are turned up. However, since the shielding members 31 are immediately restored by elasticity after passing through the components, the time period in which a gap is generated between the shielding members 31 is Extremely short. Therefore, the amount of nitrogen gas that leaks from the inside of the shield 16 to the outside through the shutter 30A even when the parts pass through is extremely small. It should be noted that, although not shown, in order to prevent the leakage of nitrogen gas when passing through the shutter 30A of the printed circuit board P more reliably, the shutter 30 as described above with respect to the transport direction is provided for each of the inlet side and the outlet side. Two shutters (double) with one shutter 30
It is of course possible to adopt a configuration in which the other shutter 30 holds the shielded state of the shielded space even when the shutter is opened.

The printed circuit board P that has passed through the shutter 30A and entered the shielded space is soldered in a high-concentration nitrogen atmosphere. As a result, it is possible to effectively prevent oxidation of terminals, copper foil, and the like on the printed circuit board P, enable the use of a flux having a low reducing action, and eliminate the flux cleaning step.

The printed circuit board P soldered by passing over the solder bath 8 passes through the shutter 30A on the outlet side in the same manner as the shutter 30A on the inlet side and goes out to the outside of the front shield 16 for the next step. Processed.

In the soldering device 15, the width of the conveyor 2 can be adjusted in the same manner as in the conventional jet type soldering device of this type. First, the upper cover 16A and the lower cover 16B forming the surrounding body 16 that surrounds the transport conveyor 2 (tracks 2a, 2b) have both tracks 2a, 2b.
Since it is not structurally related to b, it is clear that the enclosure 16 does not restrict the width adjustment of the tracks 2a and 2b.

Next, the shutter 30 (30A, 30
As for B), one track 2b is laterally adjusted to adjust the transfer width of the transfer conveyor 2, for example, both tracks 2a, 2
It is assumed that they are moved in a direction of increasing the distance between b (the right side of the paper surface in FIG. 5). Now, one shutter 30A will be described. Due to the movement of the track 2b, the shielding member 31b of the shielding members 31, 31, ... Of the shutter 30A, which is connected to the track 2b, is moved to the right along with the track 2b. When the shielding member 31b moves to the right, the upward hooking pawl 35 formed on the upper bent portion 34 of the shielding member 31b eventually comes out, as shown in FIG.
The downward hooking claw 36 of the adjacent shield member 31 is hooked to pull the adjacent shield member 31 in the same direction. In the same manner, the shielding member 31 is successively extended in the same manner, and even if the track 2b moves in the direction of expanding the width, the space between the two tracks 2a and 2b is always blocked by the shutter 30.

On the other hand, the shutter 30B has a trajectory 2b.
By moving in the same direction, the shielding member 31c connected to the track 2b among the shielding members 31, 31, ... Of the shutter 30B first moves to the right. As a result, as shown in FIG. 8, the shielding member 31c overlaps the adjacent shielding member 31 and the shielding member 3
The projecting piece 37 formed on the back surface of the 1c eventually comes into contact with the side surface of the adjacent shield member 31, and pushes the adjacent shield member 31 in the same direction. Similarly, the shielding member 31
Shutter 3 is pushed and is superimposed.
The width of 0B is narrowed in a state in which the opening between the track 2b and the outer frame 10 is closed.

By the same operation as described above, even when the track 2b moves in the direction approaching the track 2a contrary to the above case, the blockage by the shutters 30a and 30B is always secured.

The adjustment of the transfer angle of the transfer conveyor 2, that is, the tracks 2a and 2b, will be described. The transfer conveyor 2 moves up and down (up and down due to the change in angle).
However, since the relative position between the upper cover 16A and the lower cover 16B does not change, there is no effect on the shutter 30. In addition, the shield plate 26a of the lower cover 16B
Since ~ 26d is simply immersed in the molten solder in the solder bath 8, the lower cover 16B does not interfere with the solder bath 8 even when the conveyor 2 moves up and down, and The shielding function is also maintained.

As described above, according to the nitrogen-filled type soldering device 15, in the nitrogen-filled type soldering device which is a carrierless type and has a transport mechanism with a variable transport width, the solder bath for carrying out the soldering step is carried out. It is possible to reliably form a shielded space that creates the required nitrogen atmosphere in the upper space of the.

Moreover, since the shutter for shielding the conveying direction in the shielding body is provided with the closing width adjusting means, even if the width of the conveying conveyor 2 is changed, the shielding structure is not lost and the shielding space is maintained. be able to.

In particular, in this embodiment, the closing width adjusting means includes the shutter 30 and a large number of strip-shaped shielding members 3.
Since the shielding members 31 are formed of 1, 31, ... And are superposed and expanded with each other along with the movement of the track 2b, a simple structure is realized without separately requiring a driving means or the like.

In the shutter 30 according to the above-described embodiment, the shielding member 31 is made of a flexible film body, so that the mounting printed circuit board P can be mounted on the shutter 3.
Although it is configured such that 0 can be easily passed, for example, each of the shielding members 31 is configured to be swingable back and forth in a swing shape around the guide rail 32 as an axis of rotation at the upper end thereof, and the mounting printed circuit board P passes therethrough. At that time, the shielding member may be pushed up by a rotating operation.

Further, the shutter 30 according to the present invention.
The closing width adjusting means is not limited to that of the above-mentioned embodiment, in short, as long as the opening of the surrounding body 16 can be closed even when the widths of the tracks 2a and 2b are changed. Good. Although not shown in the drawings, for example, as another configuration, a film-shaped screen that can be pulled out from one end of the film, which is stored in a roll like a film used for a so-called camera, is provided between the two tracks 2a and 2b, It is also possible that the screen is pulled out from the storage roll when the distance between 2a and 2b is expanded, and conversely, the screen is pulled into the storage roll when the track distance is reduced.

As described above, according to the present invention, in a carrierless type soldering apparatus having a transport mechanism with a variable transport width, a required nitrogen atmosphere is created at least in a portion corresponding to the soldering process. However, according to the present invention, a shield such as the above is provided on a portion other than the soldering step, that is, the fluxer section or the preheater section so that the steps other than the soldering step can be performed in a nitrogen atmosphere. It does not exclude the provision. Further, although the embodiments have been described as examples in which the present invention is applied to a jet type soldering device, the present invention can also be applied to other types of soldering devices having variable track widths.

[0046]

As described above, according to the nitrogen-filled soldering apparatus according to the first aspect of the present invention, in the nitrogen-filled soldering apparatus which is a carrierless type and which has a carrying mechanism with a variable carrying width, the soldering process is performed. It is possible to surely form a shielded space that creates a required nitrogen atmosphere in the upper space of the solder bath for carrying out the step. Moreover, since the shutter for closing the opening of the surrounding body is provided with the closing width adjusting means, the shielding structure is not lost even when the width of the transfer conveyor is changed, and it is always reliable regardless of the track width. The shielded space can be maintained and formed, and a required nitrogen atmosphere can be formed.

According to the nitrogen-filled soldering apparatus of the second aspect, the width adjusting means can be easily constructed without separately providing a driving means or the like. Moreover, since the soldered product to be conveyed can pass through this shutter portion by pushing the shutter away by itself, there is no need for a shutter opening / closing mechanism, and a simple structure and reliable shielding can be achieved. ..

[Brief description of drawings]

FIG. 1 is a front sectional view showing a solder bath portion of a nitrogen-filled soldering apparatus according to an embodiment of the present invention.

2 is a partial cross-sectional side view of FIG.

FIG. 3 is a plan view showing a lower cover that constitutes the surrounding body according to the present embodiment.

FIG. 4 is a side view of the lower cover shown in FIG.

FIG. 5 is a front view showing an embodiment of a shutter that constitutes the shield according to the present embodiment together with a conveyor and the like.

FIG. 6 is a perspective view of a shutter according to this embodiment.

FIG. 7 is a partial front view showing a shutter according to the present embodiment.

FIG. 8 is a partial rear view showing the shutter according to the present embodiment.

[Explanation of symbols]

 2 Transport Conveyors 2a, 2b Orbits 8 Solder Tank 15 Nitrogen Filled Soldering Device 16 Enclosure 19 Shield 30 (30A, 30B) Shutter 31 Shielding Member (Blocking Width Adjusting Element Component) 32 Guide Rail (〃) 35 Upward Hanging Stopper (〃) 36 Downward stop stop (〃) 37 Projection piece (〃) S Tunnel-like space

Claims (2)

[Claims] 1. A solder tank is arranged below a conveyor for conveying soldered products, which has a pair of parallel tracks whose distances from each other can be adjusted. At least the soldering step is performed in a nitrogen atmosphere. A nitrogen-encapsulated soldering device comprising a shield for forming a shielded space including the transfer conveyor above the solder bath, as described above, wherein the shield is at least above the solder bath. A surrounding body that includes both tracks and forms a tunnel-shaped space extending in the extending direction of the same track; and a shutter that closes the opening of the tunnel-shaped space formed by the surrounding body, and The nitrogen-filled soldering device, wherein the shutter has a closing width adjusting means that follows the width change of the track. 2. The shutter comprises a plurality of strip-shaped shielding members, which are supported at their upper ends and are movable in the width direction, and adjacent ones can overlap each other in the width direction. The nitrogen-filled soldering device according to claim 1, wherein the shielding member is made of a highly flexible material.