Nitrogen reflow oven for PCB welding

Abstract

The utility model belongs to the technical field of reflow ovens, and particularly relates to a nitrogen reflow oven for PCB welding, which comprises a reflow oven body, a discharge slide rail and a first exhaust fan fixed in the reflow oven body, the discharge slide rail is penetratingly arranged in the reflow oven body, and the first exhaust fan is parallelly distributed on one side of the discharge slide rail. A plurality of filter boxes are arranged on the outer side of the welding furnace machine body, and a plurality of first air pipes corresponding to the filter boxes are arranged on the side, away from the discharging sliding rail, of the first exhaust fan. The exhaust gas can flow in a zigzag mode along the filtering air channel, so that the flowing speed of the exhaust gas is increased, meanwhile, the exhaust gas can be better attached to the inner wall of the filtering air channel when flowing, the attachment plate can adsorb welding slag in the exhaust gas, and the purpose of filtering the exhaust gas is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of reflow soldering furnaces, and in particular relates to a nitrogen reflow furnace for PCB board soldering. Background Art

[0002] Reflow soldering technology is not unfamiliar in the field of electronic manufacturing. This equipment has a heating circuit inside, which heats the air or nitrogen to a high enough temperature and blows it toward the circuit board with components attached, so that the solder on both sides of the components melts and bonds with the main board. The advantage of this process is that the temperature is easy to control, oxidation can be avoided during the soldering process, and the manufacturing cost is easier to control. At present, the reflow soldering furnace includes a preheating zone, a reflow zone and a cooling zone. The reflow zone is mainly used to melt the solder paste to solder the components to the PCB circuit board. In order to reduce the possibility of high-temperature oxidation of easily oxidizable materials such as solder paste or silver during the process, a large amount of nitrogen will be filled in the reflow zone to form a stable nitrogen protective layer with low oxygen content.

[0003] In the prior art, after the PCB circuit board is soldered in the reflow zone, it needs to enter the cooling zone for cooling treatment. The cooling zone exchanges heat with the PCB circuit board by blowing out cold air, and at the same time, the welding slag on the surface of the PCB circuit board can be blown away. In order to avoid the blown welding slag from accumulating in the welding furnace, at least one exhaust fan is usually provided inside the welding furnace, and the exhaust fan is used to discharge the waste gas and welding slag out of the welding furnace. However, if the waste gas containing welding slag is directly discharged, it will cause environmental pollution. Therefore, it is necessary to treat the waste gas discharged from the welding furnace. Utility Model Content

[0004] In view of this, the utility model provides a nitrogen reflow furnace for PCB board welding, the purpose of which is to enable the exhaust gas entering the filter air duct to generate convection between the partition plates through the arrangement of the partition plates and the attachment plates, so that the exhaust gas will flow in a zigzag manner along the filter air duct, thereby increasing the flow speed of the exhaust gas, and at the same time making the exhaust gas more closely attached to the inner wall of the filter air duct when flowing, so that the attachment plates can absorb the welding slag in the exhaust gas, thereby achieving the purpose of filtering the exhaust gas.

[0005] The technical solution adopted by the utility model is as follows:

[0006] It includes a welding furnace body, a discharge slide rail and a first exhaust fan fixed inside the welding furnace body, the discharge slide rail is penetrated in the welding furnace body, and the first exhaust fan is distributed in parallel on one side of the discharge slide rail, a plurality of filter boxes are arranged on the outside of the welding furnace body, and a plurality of first air pipes corresponding to the filter boxes are arranged on the side of the first exhaust fan away from the discharge slide rail, a rectangular filter duct is arranged inside the filter box, and attachment plates and a plurality of partition plates are fixed on the inner walls on both sides of the filter duct, wherein the plurality of partition plates are staggered and horizontally arranged in the filter duct, and the horizontal radial length of the partition plates is half of the horizontal diameter of the filter duct.

[0007] As a preferred technical solution, a trachea interface is provided on the side of the filter box facing the first trachea, and the first trachea and the trachea interface are interconnected, and the trachea interface is connected to the filter air duct.

[0008] Furthermore, an air outlet is provided at one end of the filtering air duct away from the trachea interface, and a filter is provided inside the air outlet.

[0009] Furthermore, a second exhaust fan is provided at one end of the air outlet away from the filter, and a second air pipe corresponding to the filter box is provided on the second exhaust fan.

[0010] Furthermore, a holding rack is provided on one side of the welding furnace body with the filter box, and a plurality of filter boxes are stacked up and down in the holding rack.

[0011] Furthermore, a water tank is provided on the opposite side of the containing rack, and the second air pipe is connected to the water tank.

[0012] Furthermore, an exhaust port is provided on the top of the water tank.

[0013] Furthermore, a box cover is movably connected to the top of the filter box.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0015] 1. Through the arrangement of the partition plate and the attachment plate, the exhaust gas entering the filter duct can generate convection between the partition plates, so that the exhaust gas will flow in a zigzag manner along the filter duct, thereby increasing the flow speed of the exhaust gas. At the same time, the exhaust gas will be more closely attached to the inner wall of the filter duct when flowing, so that the attachment plate can absorb the welding slag in the exhaust gas, thereby achieving the purpose of filtering the exhaust gas.

[0016] 2. Through the setting of the water tank, the operator can fill the inside of the water tank with refrigerant liquid, and then connect the water tank with the filter box, so that the filtered gas can enter the water tank for cooling treatment, which helps to avoid the operator being scalded by the exhaust gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be described by way of examples with reference to the accompanying drawings, in which:

[0018] Figure 1 This is a schematic diagram of the structure of a nitrogen reflow furnace for PCB board welding provided by the utility model;

[0019] Figure 2 It is a schematic diagram of the internal structure of the welding furnace body provided by the utility model;

[0020] Figure 3 It is a structural schematic diagram of the filter box provided by the utility model.

[0021] Welding furnace body-1; discharge slide rail-2; holding rack-3; filter box-4; first air pipe-5; water tank-6; exhaust port-7; first exhaust fan-8; air pipe interface-9; filter air duct-10; partition plate-11; attachment plate-12; air outlet-13; filter screen-14; second exhaust fan-15; box cover-16; second air pipe-17. DETAILED DESCRIPTION

[0022] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Embodiment 1

[0024] In the prior art, after the PCB circuit board is soldered in the reflow zone, it needs to enter the cooling zone for cooling treatment. The cooling zone exchanges heat with the PCB circuit board by blowing out cold air, and can also effectively remove the solder slag on the surface of the PCB circuit board. However, in order to prevent the blown solder slag from accumulating in the welding furnace, at least one exhaust fan is usually provided inside the welding furnace. The exhaust fan is used to extract these exhaust gases and solder slag out of the welding furnace to keep the welding furnace clean. However, in this way, the directly discharged exhaust gases with solder slag may pollute the environment, which is not conducive to the long-term use of the device.

[0025] Therefore, in order to solve the problem that the existing welding furnace directly discharges the internal waste gas to the outside, making the environment easily polluted by the welding slag in the waste gas, and to achieve the function of filtering and discharging waste gas and improving environmental protection, the utility model discloses a nitrogen reflow furnace for PCB board welding. Figure 1-Figure 3, comprising a welding furnace body 1, a discharge slide rail 2 and a first exhaust fan 8 fixed inside the welding furnace body 1, the discharge slide rail 2 is arranged inside the welding furnace body 1, and the first exhaust fan 8 is parallelly distributed on one side of the discharge slide rail 2, a plurality of filter boxes 4 are arranged on the outside of the welding furnace body 1, and a plurality of first air pipes 5 corresponding to the filter boxes 4 are arranged on the side of the first exhaust fan 8 away from the discharge slide rail 2, a rectangular filter air duct 10 is arranged inside the filter box 4, and attachment plates 12 and a plurality of partition plates 11 are fixed on the inner walls on both sides of the filter air duct 10, wherein the plurality of partition plates 11 are staggered and horizontally arranged in the filter air duct 10, and the horizontal radial length of the partition plates 11 is half of the horizontal diameter of the filter air duct;

[0026] In this embodiment, the first exhaust fan 8 guides the exhaust gas in the welding furnace body 1 into the filter box 4 through the first air pipe 5, and then absorbs and filters the welding slag in the exhaust gas through the filter duct 10 in the filter box 4.

[0027] In the above embodiment, an activated carbon layer is provided on the attachment plate 12, but the present invention is not limited thereto.

[0028] In the above embodiment, optionally, the unloading slide rail 2 can be a crawler track.

[0029] In the above embodiment, the interior of the welding furnace body 1 is provided with a preheating zone, a reflow zone and a cooling zone in sequence, and the discharge slide rails 2 are distributed in parallel below the preheating zone, the reflow zone and the cooling zone.

[0030] In the above embodiment, the first exhaust fan 8 is fixed below the cooling zone.

[0031] In this embodiment, a trachea interface 9 is provided on the side of the filter box 4 facing the first trachea 5, and the first trachea 5 and the trachea interface 9 are interconnected, and the trachea interface 9 is connected to the filter air duct 10. Through the trachea interface 9, the first trachea 5 can smoothly introduce the gas extracted by the first exhaust fan 8 into the filter box 4.

[0032] In this embodiment, an air outlet 13 is provided at one end of the filter duct 10 away from the trachea interface 9, and a filter screen 14 is provided inside the air outlet 13. The gas filtered by the filter duct 10 can be discharged from the filter box 4 through the air outlet 13, and the filter screen 14 can block the welding slag remaining in the gas in the filter duct 10.

[0033] In this embodiment, a box cover 16 is movably connected to the top of the filter box 4. Optionally, the box cover 16 is fixed to the top of the filter box 4 by screws.

[0034] In the above embodiment, the operator can remove the box cover 16 to clean the welding slag absorbed in the filter air duct 10 .

[0035] In this embodiment, a receiving rack 3 is provided on one side of the welding furnace body 1 with the filter box 4, and several filter boxes 4 are stacked up and down in the receiving rack 3. Optionally, the receiving rack 3 is formed by several drawers stacked up and down, and the filter boxes 4 are placed in the drawers.

[0036] Working principle: When the first exhaust fan 8 draws the exhaust gas in the welding furnace body 1 into the filter box 4, the exhaust gas will flow along the filter duct 10. At this time, since there are several interlaced partition plates 11 arranged horizontally inside the filter duct 10, the exhaust gas entering the filter duct 10 will experience convection between the partition plates 11. The exhaust gas will flow in a zigzag path in the filter duct 10 along the partition plates 11, thereby accelerating the flow rate of the exhaust gas in the filter duct 10. At the same time, since the partition plates 11 occupy half of the space of the filter duct 10, the exhaust gas will be more closely attached to the inner walls on both sides of the filter duct 10 when flowing, thereby improving the adsorption effect of the attachment plate 12 on the welding slag in the exhaust gas. Through the above method, the filter box 4 can filter the welding slag in the exhaust gas, which helps to improve the environmental protection effect.

[0037] During use: the operator can first put several filter boxes 4 into the holding rack 3, and connect the first air pipe 5 with the air pipe interface 9, then turn on the power of the welding furnace body 1, place the PCB board on the discharge slide rail 2, and transport the PCB board into the welding furnace body 1 through the discharge slide rail 2. Then the welding furnace body 1 can weld and cool the PCB board. At the same time, the first exhaust fan 8 can start working to draw the exhaust gas in the welding furnace body 1 into the filter box 4, and then the filter box 4 can filter the exhaust gas and discharge the filtered gas from the filter box 4 through the air outlet 13. Then, when it is necessary to clean the welding slag in the filter box 4, the operator can first remove the first air pipe 5 and the second air pipe 17, and then drag the filter box 4 out of the inside of the holding rack 3, and open the box cover 6 to clean the welding slag adsorbed inside the filter box 4.

[0038] Embodiment 2

[0039] Since the reflow zone inside the soldering furnace body 1 is the main area for soldering PCB boards, the temperature in the reflow zone is extremely high, resulting in the exhaust gas being discharged usually having a relatively high temperature. If it is discharged directly, it is very easy to cause burns to the staff. In order to solve the problem of high exhaust gas temperature and easy burns to personnel, the function of reducing the exhaust gas temperature is realized. Figure 1On the basis of the first embodiment, it further includes a second exhaust fan 15 and a water tank 6. The second exhaust fan 15 can draw the exhaust gas filtered by the filter box 4 into the water tank 6, and then cool the exhaust gas through the water tank 6. Specifically, the second exhaust fan 15 is provided at the end of the air outlet 13 away from the filter 14, and the second exhaust fan 15 is provided with a second air pipe 17 corresponding to the filter box 4. The water tank 6 is provided on the opposite side of the holding rack 3, and the second air pipe 17 is connected to the water tank 6.

[0040] In the above embodiment, the top of the water tank 6 is provided with an exhaust port 7, through which the cooled exhaust gas is discharged.

[0041] In the above embodiment, the interior of the water tank 6 is filled with water. Optionally, it may also be filled with other cooling liquids, such as liquid nitrogen, but is not limited thereto.

[0042] In the above embodiment, optionally, a screen is provided inside the exhaust port 7 to filter out moisture in the exhaust gas to be cooled.

[0043] Working principle: The second exhaust fan 15 can draw the gas in the filter box 4 into the water tank 6 through the second air pipe 17, and then the cooling liquid in the water tank 6 can exchange heat with the gas to reduce the temperature of the gas. Finally, the cooled gas is discharged to the outside through the exhaust port 7, so that the exhausted waste gas can be discharged after being filtered and cooled by welding slag in turn, which reduces environmental pollution and helps to avoid personal injury.

[0044] During use: the operator can first fill the water tank 6 with refrigerant liquid, and then connect the second air pipe 17 to the second exhaust fan 15 and the water tank 6 respectively, so that the second air pipe 17 can be connected with the second exhaust fan 15 and the water tank 6, and then turn on the second exhaust fan 15, so that the gas in the filter box 4 can be sucked into the water tank 6 along the second air pipe 17, so that the refrigerant liquid in the water tank 6 can cool the gas.

[0045] To summarize, when the nitrogen reflow furnace for PCB board welding is in use, the partition plate 11 and the attachment plate 12 are set so that the exhaust gas entering the filter duct 10 can generate convection between the partition plates 11, so that the exhaust gas will flow in a zigzag manner along the filter duct 10, thereby increasing the flow speed of the exhaust gas, and at the same time making the exhaust gas more closely attached to the inner wall of the filter duct 10 when flowing, so that the attachment plate 12 can adsorb the welding slag in the exhaust gas, thereby achieving the purpose of filtering the exhaust gas, and then through the setting of the water tank 6, the operator can fill the inside of the water tank 6 with refrigerant liquid, and then connect the water tank 6 with the filter box 4, so that the filtered gas can enter the water tank 6 for cooling treatment, and finally the exhaust port 7 is raised for discharge, thereby helping to avoid burns of the operator by the discharged exhaust gas.

[0046] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0047] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A nitrogen reflow furnace for PCB board welding, comprising a welding furnace body (1), a discharge slide rail (2) and a first exhaust fan (8) fixed inside the welding furnace body (1), the discharge slide rail (2) is inserted into the welding furnace body (1), and the first exhaust fan (8) is distributed in parallel on one side of the discharge slide rail (2), characterized in that: A plurality of filter boxes (4) are arranged on the outside of the welding furnace body (1), and a plurality of first air pipes (5) corresponding to the filter boxes (4) are arranged on a side of the first exhaust fan (8) away from the material discharge slide rail (2). A rectangular filter air duct (10) is arranged inside the filter box (4), and attachment plates (12) and a plurality of partition plates (11) are fixed on the inner walls of both sides of the filter air duct (10), wherein the plurality of partition plates (11) are arranged horizontally in an interlaced manner in the filter air duct (10), and the radial length of the partition plates (11) arranged horizontally is half of the horizontal diameter of the filter air duct.

2. A nitrogen reflow furnace for PCB board welding according to claim 1, characterized in that: The filter box (4) is provided with an air pipe interface (9) on one side facing the first air pipe (5), the first air pipe (5) and the air pipe interface (9) are in communication with each other, and the air pipe interface (9) is in communication with the filter air duct (10).

3. A nitrogen reflow furnace for PCB board welding according to claim 2, characterized in that: An air outlet (13) is provided at one end of the filtering air duct (10) away from the air pipe interface (9), and a filter screen (14) is provided inside the air outlet (13).

4. A nitrogen reflow furnace for PCB board welding according to claim 3, characterized in that: A second exhaust fan (15) is provided at one end of the air outlet (13) away from the filter screen (14), and a second air pipe (17) corresponding to the filter box (4) is provided on the second exhaust fan (15).

5. A nitrogen reflow furnace for PCB board welding according to claim 4, characterized in that: A holding rack (3) is provided on one side of the welding furnace body (1) with the filter box (4), and a plurality of filter boxes (4) are stacked up and down in the holding rack (3).

6. A nitrogen reflow furnace for PCB board welding according to claim 5, characterized in that: A water tank (6) is provided on the opposite side of the containing rack (3), and the second air pipe (17) is connected to the water tank (6).

7. A nitrogen reflow furnace for PCB board welding according to claim 6, characterized in that: An exhaust port (7) is provided on the top of the water tank (6).

8. The nitrogen reflow furnace for PCB board welding according to claim 1, characterized in that: The top of the filter box (4) is movably connected to a box cover (16).

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