Tin immersion equipment

Abstract

The utility model discloses a tin immersion device, which relates to the field of circuit board production and comprises a replacement solution, a tin immersion device and a tin immersion device, the first shell is provided with a first containing cavity, a main groove is formed in the first containing cavity, and the main groove is used for containing a replacement solution. The second shell is provided with a second containing cavity, an auxiliary groove is formed in the second containing cavity, a replacement solution is contained in the auxiliary groove, and the auxiliary groove is connected with a connecting pipeline and used for conveying the replacement solution in the auxiliary groove into the main groove; the conveying mechanism is arranged in the first shell and used for conveying the PCB, and the PCB makes contact with the replacement solution in the main groove so that a tin layer can be formed on the PCB; and the gas conveying pipeline communicates with the first containing cavity and the second containing cavity, and the gas conveying pipeline is used for conveying gas to the first containing cavity and the second containing cavity correspondingly, so that the first containing cavity and the second containing cavity are filled with the gas correspondingly. The tin immersion equipment provided by the technical scheme of the utility model can prevent divalent tin ions in the replacement solution from being oxidized and improve the quality of a PCB (Printed Circuit Board).

Description

Technical Field

[0001] The utility model relates to the technical field of circuit board production, in particular to a tin sinking device. Background Art

[0002] In modern electronic manufacturing, PCBs, as a core component of electronic products, have a quality and performance that directly impacts the reliability and stability of the entire product. The PCB immersion tin process is a crucial surface treatment technology for circuit boards, providing a strong guarantee for high-quality PCB manufacturing. The PCB immersion tin process utilizes a displacement reaction to deposit tin onto the copper surface of the PCB, forming a uniform, dense layer. The primary purpose of immersion tin is to protect the copper surface from oxidation and corrosion, while also improving the solderability and electrical performance of the PCB.

[0003] Due to the presence of air in the equipment, divalent tin ions Sn 2+ Easily oxidized by oxygen in the air to tetravalent tin ions Sn 4+ .Tetravalent tin ion Sn 4+ The presence of is not conducive to the deposition of tin, and easily causes the solution to crystallize, seriously affecting the appearance and solderability of the circuit board surface, causing quality problems. Utility Model Content

[0004] The main purpose of the utility model is to provide a tin immersion device, which aims to solve the technical problem that divalent tin ions are easily oxidized to tetravalent tin ions, thereby affecting the formation of a tin layer on the copper surface of a PCB board.

[0005] To achieve the above-mentioned purpose, the tinning equipment proposed in the present invention includes:

[0006] Replacement solution;

[0007] The first housing is provided with a first cavity, wherein a main tank is provided in the first cavity, and the main tank is used to hold the replacement solution;

[0008] The second housing is provided with a second cavity, wherein a secondary tank is provided in the second cavity, wherein the secondary tank contains the replacement solution, and wherein the secondary tank is connected to a connecting pipe, wherein the connecting pipe is also in communication with the main tank and is used to transport the replacement solution in the secondary tank to the main tank;

[0009] a conveying mechanism, disposed in the first housing and used to convey a PCB board, the PCB board being in contact with the replacement solution in the main tank so as to form a tin layer on the PCB board; and

[0010] A gas pipeline is connected to the first cavity and the second cavity, and is used to transport gas to the first cavity and the second cavity respectively, so that the gas is filled in the first cavity and the second cavity respectively.

[0011] In one embodiment, the gas is configured as a non-oxidizing gas.

[0012] In one embodiment, the gas pipeline includes a first gas branch pipe and a second gas branch pipe, the first gas branch pipe is connected to the first shell, and the second gas branch pipe is connected to the second shell.

[0013] In one embodiment, the immersion tin equipment further includes a water jet device, which includes a water spray pipe connected to the connecting pipe and used to spray the replacement solution into the main tank so that the PCB board is immersed in the replacement solution.

[0014] In one embodiment, an extension direction of the water spray pipe is perpendicular to a conveying direction of the conveying mechanism, and a plurality of the water spray pipes are provided along the conveying direction, and the plurality of the water spray pipes are arranged at intervals.

[0015] In one embodiment, the conveying mechanism includes an upper roller and a lower roller, and a gap is provided between the upper roller and the lower roller respectively. The water spray pipe is provided in the gap and sprays the solution toward the PCB board.

[0016] In one embodiment, the main tank is further connected to a reflux pipe, which is connected to the auxiliary tank. The replacement solution in the main tank flows back to the auxiliary tank through the reflux pipe.

[0017] In one embodiment, the immersion tin equipment further includes a heating system, wherein the heating system includes a heating tube, and the heating tube is provided in the auxiliary tank and is used to heat the replacement solution.

[0018] In one embodiment, the immersion tin equipment further includes a circulation system, which is connected to the auxiliary tank and is used to drive the displacement solution in the auxiliary tank to flow.

[0019] In one embodiment, the connecting pipe is further connected to a liquid pump, and the liquid pump drives the replacement solution in the auxiliary tank to be transported to the main tank through the connecting pipe.

[0020] The technical solution of the present utility model employs a method of filling the first and second cavities with gas to prevent the replacement solution from coming into contact with oxygen and being oxidized, thereby preventing the replacement solution from crystallizing. Specifically, a first cavity is provided within the first housing, wherein a main tank is provided within the first cavity, and the main tank contains the replacement solution. A second cavity is provided within the second housing, wherein a secondary tank is provided within the second cavity, and the secondary tank also contains the replacement solution, which is transported to the main tank via a connecting pipe. The PCB is transported to the main tank via a conveying mechanism, where it comes into contact with the replacement solution in the main tank, forming a tin layer on the PCB. Gas is introduced into the first and second cavities through gas pipelines, respectively, filling the first and second cavities with gas to increase the air pressure in the first and second cavities, while simultaneously discharging air from the first and second cavities and preventing external air from entering the first and second cavities. This prevents the replacement solution from coming into contact with air and being oxidized, thereby ensuring the concentration of divalent tin ions in the replacement solution and improving the quality of the PCB. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0022] Figure 1 This is a structural diagram of the main tank of the tin sinking equipment embodiment provided by the utility model;

[0023] Figure 2 A side structural diagram of an embodiment of the immersion tin equipment provided by the present invention;

[0024] Figure 3 This is a schematic top view of the structure of an embodiment of the immersion tin equipment provided by the utility model.

[0025] Description of Figure Numbers:

[0026] 100. First shell; 110. Main tank; 200. Second shell; 210. Sub-tank; 300. Gas pipeline; 310. First gas branch; 320. Second gas branch; 400. Conveying mechanism; 510. Gas; 520. Replacement solution; 600. Water jet device; 610. Water spray pipe; 710. Connecting pipe; 720. Liquid pump; 730. Return pipe; 800. Heating pipe; 900. Circulation system.

[0027] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts shall fall within the scope of protection of the present invention.

[0029] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0030] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0031] In the prior art, due to the presence of air in the equipment, divalent tin ions Sn 2+ Easily oxidized by oxygen in the air to tetravalent tin ions Sn 4+ .Tetravalent tin ion Sn 4+ The presence of is not conducive to the deposition of tin, and easily causes the solution to crystallize, seriously affecting the appearance and solderability of the circuit board surface, causing quality problems.

[0032] The utility model provides a tin sinking device.

[0033] See also Figures 1 to 3As shown, in one embodiment of the present invention, the tin sinking device includes: a replacement solution 520, a first shell 100, a second shell 200, a conveying mechanism 400 and a gas pipeline 300; wherein the first shell 100 is provided with a first cavity, a main tank 110 is provided in the first cavity, and the main tank 110 is used to hold the replacement solution 520; the second shell 200 is provided with a second cavity, a sub-tank 210 is provided in the second cavity, and the sub-tank 210 holds the replacement solution 520, and the sub-tank 210 is connected to a connecting pipe 710, and the connecting pipe 710 is also connected to the main tank 110 and is used to transport the replacement solution 520 in the auxiliary tank 210 to the main tank 110; the conveying mechanism 400 is arranged in the first shell 100 and is used to transport the PCB board, which contacts the replacement solution 520 in the main tank 110 to form a tin layer on the PCB board; the gas pipeline 300 is connected to the first cavity and the second cavity, and the gas pipeline 300 is used to transport gas 510 to the first cavity and the second cavity respectively, so that the gas 510 is filled in the first cavity and the second cavity respectively.

[0034] First, it should be noted that the replacement solution 520 contains a large amount of divalent tin ions, which undergo a replacement reaction with copper to form a tin layer on the copper surface. When the conveying mechanism 400 conveys the PCB board through the main tank 110, the PCB board is immersed in the replacement solution 520. The copper on the PCB board undergoes a replacement reaction with the divalent tin ions in the replacement solution 520, forming a tin layer on the copper surface to protect the copper surface from oxidation and corrosion, while also improving the solderability and electrical performance of the PCB board. The replacement solution 520 is contained in the auxiliary tank 210 and is transported to the main tank 110 through the connecting pipe 710, so that the solution in the main tank 110 always maintains a certain capacity and circulates continuously, ensuring the replacement effect of the PCB board.

[0035] In a specific implementation, the first housing 100 forms a first cavity, with a main tank 110 disposed within the first cavity. The main tank 110 holds a replacement solution 520. A conveying device transports a PCB through the main tank 110, where it comes into contact with the replacement solution 520 within the main tank 110 to undergo a replacement reaction. The conveying device can be a chain conveyor 400, a roller conveyor 400, or a belt conveyor 400, etc., and is not limited in this embodiment. The second housing 200 is located on one side of the first housing 100 and forms a second cavity. A secondary tank 210 is disposed within the second cavity, also holding a replacement solution 520. The replacement solution 520 in the secondary tank 210 is transported to the main tank 110 via a connecting pipe 710, where it reacts with the PCB. It will be appreciated that the connecting pipe 710 is also connected to a liquid pump 720, which drives the replacement solution 520 in the secondary tank 210 through the connecting pipe 710 to the main tank 110.

[0036] refer to Figure 2As shown, the main tank 110 is further connected to a reflux pipe 730, which is connected to the auxiliary tank 210. The replacement solution 520 in the main tank 110 is refluxed to the auxiliary tank 210 through the reflux pipe 730. Specifically, the reflux pipe 730 includes a reflux branch pipe and a reflux main pipe. Multiple reflux branch pipes are provided along the length of the main tank 110. The reflux branch pipes are connected to the reflux main pipe, which is connected to the auxiliary tank 210. The collected replacement solution 520 is transported back to the auxiliary tank 210. In this way, the replacement solution 520 can be circulated between the main tank 110 and the auxiliary tank 210.

[0037] It is understandable that, since there is other space in the first and second chambers and there is air, the oxygen in the air reacts with the replacement solution 520 to oxidize the divalent tin ions into tetravalent tin ions, thereby reducing the concentration of divalent tin ions in the solution, affecting the replacement reaction with the PCB board. In addition, the tetravalent tin ions easily cause the replacement solution 520 to crystallize, further affecting the replacement reaction between the replacement solution 520 and the PCB board. Figure 2 As shown, in this embodiment, the first housing 100 and the second housing 200 are respectively connected to a gas pipeline 300. The gas pipeline 300 is connected to the first cavity and the second cavity, respectively, and delivers gas 510 to the spaces in the two cavities. The gas 510 fills the spaces, expelling the air in the spaces, increasing the air pressure in the spaces, and preventing external air from entering the spaces. In this way, the gas 510 can isolate the solution from contact with air, thereby preventing the divalent tin ions in the solution from being oxidized. It should be noted that the gas 510 delivered by the gas pipeline 300 does not react with the solution, ensuring the stability of the solution.

[0038] The present invention employs a method of filling the first and second cavities with gas 510 to prevent the replacement solution 520 from coming into contact with oxygen and causing oxidation, thereby preventing the replacement solution 520 from crystallizing. Specifically, a first cavity is provided within the first housing 100, within which a main tank 110 is disposed. The main tank 110 contains the replacement solution 520. A second cavity is provided within the second housing 200, within which a secondary tank 210 is disposed. The secondary tank 210 also contains the replacement solution 520, which is then transported to the main tank 110 via a connecting conduit 710. The PCB is then transported to the main tank 110 via a transport mechanism 400, where it comes into contact with the replacement solution 520 within the main tank 110, forming a tin layer on the PCB. The gas pipeline 300 introduces gas 510 into the first and second chambers, respectively, and allows the gas 510 to fill the first and second chambers, thereby increasing the air pressure in the first and second chambers, discharging the air in the first and second chambers while preventing external air from entering the first and second chambers. This prevents the replacement solution 520 from being oxidized by contact with air, thereby ensuring the concentration of divalent tin ions in the replacement solution 520 and improving the quality of the PCB board.

[0039] In one embodiment, the gas 510 is configured as a non-oxidizing gas, such as nitrogen, an inert gas, etc. In a specific implementation process, nitrogen is usually introduced into the first cavity and the second cavity.

[0040] refer to Figure 2 As shown, in one embodiment, the gas pipeline 300 includes a first gas branch pipe 310 and a second gas branch pipe 320 . The first gas branch pipe 310 is connected to the first shell 100 , and the second gas branch pipe 320 is connected to the second shell 200 .

[0041] Specifically, the gas pipeline 300 also includes a main gas pipe, which connects to the first gas branch pipe 310 and the second gas branch pipe 320, respectively. It is understood that valves are also provided on the first gas branch pipe 310 and the second gas branch pipe 320 to control the opening and closing of the pipes. The first housing 100 defines an air inlet connected to the first chamber. The first gas branch pipe 310 communicates with the air inlet of the first housing. The air inlet is located above the main tank 110, allowing nitrogen to contact the surface of the solution and ensuring that the solution is isolated from air. Correspondingly, the second housing 200 defines an air inlet connected to the second chamber and is located above the secondary tank 210. The second gas branch pipe 320 communicates with the air inlet of the second housing 200 and delivers gas 510 to the second chamber.

[0042] Multiple first and second gas branch pipes 310, 320 are provided, spaced apart along the delivery direction. This allows gas 510 to be introduced at intervals along the length of the primary tank 110 and the secondary tank 210, ensuring that gas 510 uniformly fills the first and second cavities. Accordingly, the first and second housings 100, 200 each have multiple gas inlets, corresponding to the first and second gas branch pipes 310, 320, respectively.

[0043] In one embodiment, the immersion tin equipment also includes a water jet device 600, which includes a water spray pipe 610. The water spray pipe 610 is connected to the connecting pipe 710 and is used to spray the replacement solution 520 into the main tank 110 so that the PCB board is immersed in the replacement solution 520.

[0044] During implementation, the sidewall of the water spray pipe 610 includes a water outlet, which sprays the replacement solution 520 diagonally toward the PCB to avoid significant impact on the PCB. The water spray pipe 610 discharges the replacement solution 520 into the main tank 110, ensuring a constant volume of replacement solution 520 within the main tank 110 and immersing the PCB in the replacement solution 520. The water spray pipe 610 also sprays the replacement solution 520 toward the PCB, ensuring a continuous flow of the replacement solution 520. This ensures that the replacement solution 520 in contact with the PCB has a certain concentration of divalent tin ions, improving replacement efficiency and effectiveness.

[0045] Furthermore, the direction of the water spray pipe 610 extends perpendicular to the conveying direction of the conveying mechanism 400. Multiple water spray pipes 610 are provided along the conveying direction, and the multiple water spray pipes 610 are spaced apart. In practice, the conveying direction of the conveying mechanism 400 aligns with the length of the main tank 110. The multiple water spray pipes 610 are spaced apart along the length of the main tank 110. This ensures that the PCBs are constantly exposed to the replacement solution 520 containing a certain concentration of divalent tin ions throughout the entire conveying process, further improving the replacement efficiency and effectiveness.

[0046] In one embodiment, the conveying mechanism 400 includes an upper roller and a lower roller, and a gap is provided between the upper roller and the lower roller respectively. The water spraying pipe 610 is provided in the gap and sprays the solution toward the PCB board.

[0047] During specific implementation, the PCB is positioned between the upper and lower rollers and conveyed through the two roller layers. A gap exists between two adjacent rollers in the upper roller layer. The upper water spray pipes 610 are located within this gap and spray the replacement solution 520 toward the PCB. It will be appreciated that a gap exists between two adjacent rollers in the lower roller layer, which accommodates the lower water spray pipes 610. The upper and lower water spray pipes 610 are staggered in the conveying direction.

[0048] refer to Figure 3 As shown, in one embodiment, the immersion tin equipment also includes a heating system, which includes a heating tube 800. The heating tube 800 is arranged in the auxiliary tank 210 and is used to heat the replacement solution 520, so that the replacement solution 520 maintains a certain temperature and is transported to the main tank 110 to ensure a certain reaction environment, thereby improving the replacement efficiency with the PCB board.

[0049] Continue to refer Figure 3 As shown, in one embodiment, the immersion tin equipment further includes a circulation system 900 , which is connected to the auxiliary tank 210 and is used to drive the replacement solution 520 in the auxiliary tank 210 to flow.

[0050] During specific implementation, the auxiliary tank 210 has a certain extension length, and the displacement solution 520 therein needs to maintain a certain fluidity to ensure the uniformity and consistency of the displacement solution 520 throughout the auxiliary tank 210, such as the concentration of divalent tin ions and the solution temperature. In this embodiment, a circulation system 900 is provided to drive the displacement solution 520 in the auxiliary tank 210 to flow. It will be understood that the circulation system 900 includes a circulation pump and a pipeline, and the pipeline is connected to the auxiliary tank 210. The circulation pump drives the displacement solution 520 to flow.

[0051] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made based on the contents of the present invention specification and drawings, or direct / indirect application in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A tin immersion equipment, characterized in that, include: Replacement solution; The first housing is provided with a first cavity, wherein a main tank is provided in the first cavity, and the main tank is used to hold the replacement solution; The second housing is provided with a second cavity, wherein a secondary tank is provided in the second cavity, wherein the secondary tank contains the replacement solution, and wherein the secondary tank is connected to a connecting pipe, wherein the connecting pipe is also in communication with the main tank and is used to transport the replacement solution in the secondary tank to the main tank; a conveying mechanism, disposed in the first housing and used to convey a PCB board, wherein the PCB board contacts the replacement solution in the main tank to form a tin layer on the PCB board; as well as A gas pipeline is connected to the first cavity and the second cavity, and is used to transport gas to the first cavity and the second cavity respectively, so that the gas is filled in the first cavity and the second cavity respectively.

2. The immersion tin equipment according to claim 1, characterized in that The gas is configured as a non-oxidizing gas.

3. The immersion tin equipment according to claim 1 or 2, characterized in that: The gas pipeline includes a first gas branch pipe and a second gas branch pipe, wherein the first gas branch pipe is connected to the first shell, and the second gas branch pipe is connected to the second shell.

4. The immersion tin equipment according to claim 1, characterized in that: The immersion tin equipment also includes a water jet device, which includes a water spray pipe. The water spray pipe is connected to the connecting pipe and is used to spray the replacement solution into the main tank so that the PCB board is immersed in the replacement solution.

5. The immersion tin equipment according to claim 4, characterized in that: The extension direction of the water spray pipe is perpendicular to the conveying direction of the conveying mechanism, and a plurality of the water spray pipes are provided along the conveying direction, and the plurality of the water spray pipes are arranged at intervals.

6. The immersion tin equipment according to claim 5, characterized in that: The conveying mechanism includes an upper roller and a lower roller, and gaps are respectively provided between the upper roller and the lower roller. The water spray pipe is provided in the gap and sprays the solution toward the PCB board.

7. The immersion tin equipment according to claim 1, characterized in that: The main tank is further connected to a reflux pipe, which is connected to the auxiliary tank. The replacement solution in the main tank flows back to the auxiliary tank through the reflux pipe.

8. The immersion tin equipment according to claim 1, characterized in that: The tin immersion equipment further includes a heating system, which includes a heating tube. The heating tube is provided in the auxiliary tank and is used to heat the replacement solution.

9. The immersion tin equipment according to claim 1, characterized in that: The immersion tin equipment further includes a circulation system, which is connected to the auxiliary tank and is used to drive the replacement solution in the auxiliary tank to flow.

10. The immersion tin equipment according to claim 1, characterized in that: The connecting pipe is further connected to a liquid pump, and the liquid pump drives the replacement solution in the auxiliary tank to be transported to the main tank through the connecting pipe.

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