A stable reflow soldering structure for circuit board assembly

Abstract

This utility model discloses a stable reflow soldering structure for circuit board assembly, belonging to the field of circuit board assembly reflow soldering technology. Its key technical features include a frame with a support component inside, and a circuit board body inside the support component. This solves the problems of existing stable reflow soldering structures for circuit board assembly, which typically use simple flat-plate carriers to support the circuit board at the bottom. Furthermore, the support components are mostly rigidly connected, which is not conducive to buffering vibrations and absorbing thermal stress during the soldering process. This leads to the circuit board easily shifting during transport and soldering, with warping at the four corners due to concentrated thermal stress, affecting the flatness of the solder joints and the stability of the soldering quality. Moreover, the positioning of the circuit board during transport often relies on mechanical hard-contact adjustment, which is not convenient for flexibly adjusting the positioning force according to different circuit board sizes, resulting in low positioning accuracy, easy scratching of the circuit board edges, and affecting the accuracy of the soldering position.

Description

Technical Field

[0001] This utility model relates to the field of circuit board assembly reflow soldering technology, and in particular to a stable reflow soldering structure for circuit board assembly. Background Technology

[0002] In the circuit board assembly process, reflow soldering is a key process for achieving electrical and mechanical connections between components and the PCB board, and its soldering quality directly affects the performance and reliability of the circuit board.

[0003] During reflow soldering, solder splattered due to high-temperature solder explosion may adhere to any gold finger contact on the PCB. In order to solve this problem, existing technologies usually use a custom carrier for the PCB and cover the gold finger contact of the printed circuit board with a cover plate to prevent solder splattered due to high-temperature solder explosion from adhering to the gold finger contact of the circuit board during the reflow soldering process and producing defective boards.

[0004] The existing patent (publication number: CN222884902U) discloses a reflow soldering positioning and fixing structure based on a PCB carrier. By magnetically fixing an iron cover plate on the circuit board, the removable peel-off film on the cover plate can shield the gold finger area on the circuit board. This prevents solder splatter caused by high-temperature solder explosion when soldering any area on the circuit board, thus preventing solder splatter from adhering to the gold finger area. This effectively protects the gold finger contacts on the circuit board, improves their conductivity, and reduces the scrap of defective boards caused by solder adhesion to the gold fingers.

[0005] To address the aforementioned issues, existing patents offer solutions. However, existing stable reflow soldering structures for circuit board assembly typically use simple flatbed carriers to support the circuit board from the bottom. Furthermore, the supporting components are mostly rigidly connected, which is not conducive to buffering vibrations and absorbing thermal stress during the soldering process. This leads to the circuit board easily shifting during transport and soldering, with corners warping due to concentrated thermal stress, affecting the flatness of the solder joints and the stability of the soldering quality. Moreover, the positioning of the circuit board during transport relies heavily on mechanical hard-contact adjustments, making it difficult to flexibly adjust the positioning force according to different circuit board sizes. This results in low positioning accuracy, easy scratching of the circuit board edges, and affects the accuracy of the soldering position.

[0006] To address this, a stable reflow soldering structure for circuit board assembly is proposed. Utility Model Content

[0007] The purpose of this invention is to provide a stable reflow soldering structure for circuit board assembly. This structure addresses the problems of existing stable reflow soldering structures for circuit board assembly, which typically use simple flat plate carriers to support the circuit board from the bottom. The supporting components are often rigidly connected, which is not conducive to buffering vibrations and absorbing thermal stress during the soldering process. This leads to the circuit board easily shifting during transport and soldering, with corners warping due to concentrated thermal stress, affecting the flatness of the solder joints and the stability of the soldering quality. Furthermore, the positioning of the circuit board during transport often relies on mechanical hard contact adjustment, which is not convenient for flexibly adjusting the positioning force according to different circuit board sizes. This results in low positioning accuracy, easy scratching of the circuit board edges, and affects the accuracy of the soldering position.

[0008] To achieve the above objectives, this utility model provides the following technical solution: a stable reflow soldering structure for circuit board assembly, comprising a frame, a support assembly inside the frame, a circuit board body inside the support assembly, a centering guide assembly inside the frame, a support base at the bottom of the circuit board body, a telescopic support rod fixedly connected inside the support base, a placement plate fixedly connected to the top of the telescopic support rod, the placement plate being located at the bottom of the circuit board body, connecting rods slidably connected to both sides of the placement plate, the side of the connecting rod away from the placement plate being fixedly connected to the support base, a buffer spring sleeved on the outer side of the connecting rod, a slot formed at the top of the connecting rod, a silicone pressure plate engaging at the top of the slot, a guide rail connected to the top of the support base, and the guide rail slidably connected to the silicone pressure plate.

[0009] Preferably, the centering guide assembly includes a vortex pump fixedly connected inside the frame, the output end of the vortex pump is connected to a gas distribution pipe, and a control valve is provided on the outside of the gas distribution pipe.

[0010] Preferably, a sealing sleeve is fixedly connected inside the frame, and the air inlet of the sealing sleeve is connected to the air outlet of the air distribution pipe.

[0011] Preferably, a piston rod is slidably connected inside the sealing sleeve, and a guide plate is fixedly connected to the outside of the piston rod.

[0012] Preferably, a heating module is fixedly connected to the left side of the top of the frame, and a cooling module is fixedly connected to the right side of the top of the frame.

[0013] Preferably, an air storage tank is fixedly connected to the outside of the frame, the air storage tank is fixedly connected to the input end of the vortex pump, and return pipes are connected to both sides of the air storage tank, and the return pipes are connected to the air distribution pipes.

[0014] Preferably, a drive motor is fixedly connected to the outside of the frame, and a conveyor belt is mounted on the output end of the drive motor via a transmission shaft and a synchronous belt.

[0015] Preferably, guide ramps are fixedly connected to both sides of the frame, and the guide ramps are located on both sides of the conveyor belt.

[0016] Preferably, image acquisition cameras are installed on both sides of the frame, and the image acquisition cameras are located on top of the conveyor belt.

[0017] Preferably, a pressure reducing valve is provided on the outside of the return pipe.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] 1. This application achieves stable support for the circuit board and prevents the corners from warping through the support components, thereby improving the stability and flatness of the circuit board during the welding process. Compared with the traditional reflow soldering structure, it can realize the functions of flexibly pressing and fixing the four corners of the circuit board through silicone pressure plates, buffering vibration with buffer springs, and adaptive support height of telescopic support rods. It solves the problems of circuit boards being prone to displacement due to vibration, uneven welding due to warping of the four corners caused by thermal stress, and damage to the circuit board due to excessive support rigidity during welding in traditional devices.

[0020] 2. This application achieves precise centering of the circuit board through the centering guide component, improving the accuracy and consistency of the soldering position. Compared with the traditional reflow soldering structure, it can realize the functions of flexible clamping and centering by gas-driven guide plate, stable adjustment of gas pressure by control valve and pressure reducing valve, and gas recycling to ensure stable guiding force. It solves the problems of low guiding accuracy, easy damage to circuit board by mechanical hard contact, and misalignment or cold solder joint caused by position deviation in traditional devices. Attached Figure Description

[0021] Figure 1 This is an overall structural diagram of a stable reflow soldering structure for circuit board assembly according to the present invention;

[0022] Figure 2 This is a plan view of the frame of this utility model;

[0023] Figure 3 This is a cross-sectional schematic diagram of the frame of this utility model;

[0024] Figure 4 This is a schematic diagram of the structure of the support component of this utility model;

[0025] Figure 5 This is a schematic diagram of the centering and guiding component of this utility model;

[0026] Figure 6 This is a schematic diagram of the structure of the gas storage tank of this utility model;

[0027] Figure 7 This is a schematic diagram of the heating module and cooling module of this utility model.

[0028] In the diagram: 1. Frame; 2. Circuit board body; 3. Image acquisition camera; 4. Support assembly; 401. Support base; 402. Telescopic support rod; 403. Placement plate; 404. Connecting rod; 405. Buffer spring; 406. Silicone pressure plate; 407. Guide slide rail; 5. Centering and guiding assembly; 501. Vortex pump; 502. Gas distribution pipe; 503. Control valve; 504. Sealing sleeve; 505. Piston rod; 506. Guide plate; 6. Heating module; 7. Cooling module; 8. Gas storage tank; 9. Return pipe; 10. Drive motor; 11. Conveyor belt; 12. Guide ramp; 13. Pressure reducing valve. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] Please see Figure 1-7 The present invention provides the following technical solution:

[0031] A stable reflow soldering structure for circuit board assembly includes a frame 1. A support assembly 4 is disposed inside the frame 1, and a circuit board body 2 is disposed inside the support assembly 4. A centering guide assembly 5 is disposed inside the frame 1. The support assembly 4 includes a support base 401 disposed at the bottom of the circuit board body 2. A telescopic support rod 402 is fixedly connected inside the support base 401. A placement plate 403 is fixedly connected to the top of the telescopic support rod 402. The placement plate 403 is located at the bottom of the circuit board body 2. Connecting rods 404 are slidably connected to both sides of the placement plate 403. The side of the connecting rod 404 away from the placement plate 403 is fixedly connected to the support base 401. A buffer spring 405 is sleeved on the outer side of the connecting rod 404. A slot is formed at the top of the connecting rod 404, and a silicone pressure plate 406 is engaged at the top of the slot. A guide rail 407 is connected to the top of the support base 401, and the guide rail 407 is slidably connected to the silicone pressure plate 406.

[0032] In this embodiment: by placing the circuit board on the placement plate 403, the telescopic support rod 402 inside the support base 401 adaptively adjusts its height according to the thickness of the circuit board, providing stable bottom support for the placement plate 403. When the circuit board vibrates during transportation or welding, the placement plate 403 slides along the connecting rod 404, and the buffer spring 405 on the outside of the connecting rod 404 deforms accordingly to absorb vibration energy and prevent the circuit board from shifting due to vibration. The silicone pressure plate 406 at the top of the connecting rod 404 is fixed by the slot and slides along the guide rail 407 of the support base 401 to flexibly press the circuit board from the four corners, which not only prevents the four corners from warping due to thermal stress during welding, but also avoids rigid contact damage to the circuit board.

[0033] Specifically, such as Figure 5 As shown, the centering guide assembly 5 includes a vortex pump 501 fixedly connected inside the frame 1. The output end of the vortex pump 501 is connected to a gas distribution pipe 502, and a control valve 503 is provided on the outside of the gas distribution pipe 502.

[0034] Specifically, such as Figure 5 As shown, a sealing sleeve 504 is fixedly connected inside the frame 1, and the air inlet of the sealing sleeve 504 is connected to the air outlet of the air distribution pipe 502.

[0035] Specifically, such as Figure 5 As shown, a piston rod 505 is slidably connected inside the sealing sleeve 504, and a guide plate 506 is fixedly connected to the outside of the piston rod 505.

[0036] In this embodiment: when the vortex pump 501 obtains gas from the gas storage tank 8 and delivers it through the gas distribution pipe 502, the control valve 503 on the outside of the gas distribution pipe 502 adjusts the gas flow rate. After the gas enters the sealing sleeve 504 inside the frame 1, it pushes the piston rod 505 inside the sealing sleeve 504 to slide. The piston rod 505 drives the outer guide plate 506 to move synchronously. The guide plates 506 on both sides cooperate with each other to apply a smooth thrust from both sides of the circuit board, pushing it to the center position of the conveyor belt 11 to achieve centering positioning. Since the gas drive is flexible, it can avoid mechanical hard contact damage to the circuit board, while ensuring positioning accuracy.

[0037] Specifically, such as Figure 2 , Figure 7 As shown, a heating module 6 is fixedly connected to the left side of the top of the frame 1, and a cooling module 7 is fixedly connected to the right side of the top of the frame 1.

[0038] Specifically, such as Figure 5 As shown, an air tank 8 is fixedly connected to the outside of the frame 1. The air tank 8 is fixedly connected to the input end of the vortex pump 501. Both sides of the air tank 8 are connected to return pipes 9, which are connected to the air distribution pipe 502.

[0039] In this embodiment: by setting a heating module 6 and a cooling module 7, after the circuit board is centered, it moves continuously with the conveyor belt 11. First, it passes the heating module 6 on the top left side of the frame 1. The heating module 6 releases heat, causing the solder paste on the circuit board to gradually melt, realizing the soldering of components to the circuit board. Subsequently, the circuit board continues to move to the cooling module 7 on the top right side of the frame 1. The cooling module 7 quickly removes the heat, causing the molten solder to solidify rapidly, and the solder joint to set, ensuring the stability of mechanical strength and electrical performance after soldering. A gas storage tank 8 and a return pipe 9 are installed. The gas storage tank 8 on the outside of the frame 1 is used to store gas and provide a stable gas source for the centering and guiding component 5. When the vortex pump 501 is working, the gas enters the vortex pump 501 from the gas storage tank 8, is pressurized, and is delivered to the sealing sleeve 504 through the gas distribution pipe 502. Some of the gas that is not completely consumed flows back to the gas storage tank 8 from the gas distribution pipe 502 through the return pipe 9, forming a gas cycle. This reduces gas waste and ensures that the vortex pump 501 can always obtain a continuous and stable gas source, ensuring stable gas pressure during the centering and guiding process.

[0040] Specifically, such as Figure 1 As shown, a drive motor 10 is fixedly connected to the outside of the frame 1, and a conveyor belt 11 is installed at the output end of the drive motor 10 through a transmission shaft and a synchronous belt.

[0041] Specifically, such as Figure 2 As shown, guide ramps 12 are fixedly connected to both sides of the frame 1, and the guide ramps 12 are located on both sides of the conveyor belt 11.

[0042] In this embodiment: by setting up a drive motor 10 and a conveyor belt 11, after the drive motor 10 on the outside of the frame 1 starts, its output end transmits power to the conveyor belt 11 through the transmission shaft and synchronous belt, driving the conveyor belt 11 to rotate at a uniform speed. The conveyor belt 11 carries the circuit board body 2 and smoothly transports it from the entrance to various workstations such as guiding, centering, heating, and cooling, realizing the automated movement of the circuit board in the welding process and ensuring the orderly connection of each process. By setting up guide ramps 12, when the circuit board enters the device, the guide ramps 12 on both sides of the frame 1 guide it. Since the guide ramps 12 are located on both sides of the conveyor belt 11 and are inclined, the circuit board can be accurately placed in the center of the conveyor belt 11, ensuring smooth transportation.

[0043] Specifically, such as Figure 1 , Figure 2 As shown, image acquisition cameras 3 are installed on both sides of the frame 1, and the image acquisition cameras 3 are located on top of the conveyor belt 11.

[0044] Specifically, such as Figure 7 As shown, a pressure reducing valve 13 is installed on the outside of the return pipe 9.

[0045] In this embodiment: by setting an image acquisition camera 3, during the process of conveying the circuit board on the conveyor belt 11, the image acquisition camera 3 continuously captures the position status of the circuit board. The image captured by the camera can reflect in real time whether the circuit board is in the center of the conveyor belt 11, whether there is any offset, etc., providing a reference for the adjustment of the centering guide component 5. By setting a pressure reducing valve 13, when the gas flows back from the gas distribution pipe 502 to the gas storage tank 8 through the return pipe 9, the pressure reducing valve 13 on the outside of the return pipe 9 adjusts the gas pressure. By controlling the pressure of the return gas, the gas pressure in the gas storage tank 8 can be avoided from being too high or too low, ensuring the stability of the gas source pressure at the input end of the vortex pump 501, thereby ensuring that the gas pressure delivered from the gas distribution pipe 502 to the sealing sleeve 504 is constant, making the thrust of the guide plate 506 stable, and preventing over- or under-guidance due to gas pressure fluctuations.

[0046] Working principle: When using this circuit board to assemble a reflow soldering structure, the circuit board body 2 is first placed on the placement plate 403. The telescopic support rod 402 in the support base 401 provides bottom support for the placement plate 403. When the two sides of the placement plate 403 slide along the connecting rod 404, the buffer spring 405 on the outside of the connecting rod 404 deforms accordingly to provide a buffering effect. The silicone pressure plate 406 at the top of the connecting rod 404 is engaged with the connecting rod 404 through a slot and slides along the guide rail 407 at the top of the support base 401, forming a flexible pressing and fixing from the four corners of the circuit board to prevent the four corners of the circuit board from warping during soldering. Then, the circuit board body 2 enters the conveyor belt 11 through the guide inclined plate 12. The drive motor 10 drives the conveyor belt 11 to transport the circuit board through the transmission shaft and synchronous belt. When the centering guide component 5 is working, the storage... Gas tank 8 provides gas source for vortex pump 501. Gas output from vortex pump 501 is transported through gas distribution pipe 502. Control valve 503 on the outside of gas distribution pipe 502 regulates gas flow. After gas enters the sealing sleeve 504 inside the frame 1, it pushes the piston rod 505 inside the sealing sleeve 504 to slide. The piston rod 505 drives the guide plate 506 on the outside to move synchronously. The two guide plates 506 cooperate to center and guide the circuit board on the conveyor belt 11. Part of the gas in the gas distribution pipe 502 flows back to gas tank 8 through return pipe 9. Pressure reducing valve 13 on the outside of return pipe 9 regulates the return gas pressure to ensure stable gas circulation. After the circuit board is centered and positioned, it passes through heating module 6 for heating and welding and cooling module 7 for cooling and shaping along with conveyor belt 11, completing the entire reflow welding process.

[0047] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A stable reflow soldering structure for circuit board assembly, comprising a frame (1), characterized in that: The frame (1) is internally provided with a support assembly (4), and the support assembly (4) is internally provided with a circuit board body (2). The frame (1) is internally provided with a centering guide assembly (5). The support assembly (4) includes a support base (401) disposed at the bottom of the circuit board body (2). A telescopic support rod (402) is fixedly connected inside the support base (401). A placement plate (403) is fixedly connected to the top of the telescopic support rod (402). The placement plate (403) is located at the bottom of the circuit board body (2). The placement plate (403) has connecting rods (404) slidably connected to both sides. The side of the connecting rod (404) away from the placement plate (403) is fixedly connected to the support base (401). A buffer spring (405) is sleeved on the outside of the connecting rod (404). A slot is opened on the top of the connecting rod (404). A silicone pressure plate (406) is engaged on the top of the slot. A guide rail (407) is connected to the top of the support base (401). The guide rail (407) is slidably connected to the silicone pressure plate (406).

2. The stable reflow soldering structure for circuit board assembly according to claim 1, characterized in that: The centering and guiding component (5) includes a vortex pump (501) fixedly connected inside the frame (1). The output end of the vortex pump (501) is connected to a gas distribution pipe (502), and a control valve (503) is provided on the outside of the gas distribution pipe (502).

3. The stable reflow soldering structure for circuit board assembly according to claim 2, characterized in that: A sealing sleeve (504) is fixedly connected inside the frame (1), and the air inlet of the sealing sleeve (504) is connected to the air outlet of the air distribution pipe (502).

4. A stable reflow soldering structure for circuit board assembly according to claim 3, characterized in that: A piston rod (505) is slidably connected inside the sealing sleeve (504), and a guide plate (506) is fixedly connected to the outside of the piston rod (505).

5. A stable reflow soldering structure for circuit board assembly according to claim 1, characterized in that: A heating module (6) is fixedly connected to the left side of the top of the frame (1), and a cooling module (7) is fixedly connected to the right side of the top of the frame (1).

6. A stable reflow soldering structure for circuit board assembly according to claim 2, characterized in that: An air tank (8) is fixedly connected to the outside of the frame (1). The air tank (8) is fixedly connected to the input end of the vortex pump (501). Both sides of the air tank (8) are connected to return pipes (9), and the return pipes (9) are connected to the gas distribution pipes (502).

7. A stable reflow soldering structure for circuit board assembly according to claim 1, characterized in that: A drive motor (10) is fixedly connected to the outside of the frame (1), and a conveyor belt (11) is installed at the output end of the drive motor (10) through a transmission shaft and a synchronous belt.

8. A stable reflow soldering structure for circuit board assembly according to claim 7, characterized in that: Guide ramps (12) are fixedly connected to both sides of the frame (1), and the guide ramps (12) are located on both sides of the conveyor belt (11).

9. A stable reflow soldering structure for circuit board assembly according to claim 7, characterized in that: Image acquisition cameras (3) are installed on both sides of the frame (1), and the image acquisition cameras (3) are located on the top of the conveyor belt (11).

10. A stable reflow soldering structure for circuit board assembly according to claim 6, characterized in that: A pressure reducing valve (13) is provided on the outside of the return pipe (9).

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