A reflow soldering jig

Abstract

The utility model relates to a reflow soldering fixture, including the base plate, the top surface of base plate is equipped with fixed groove, the center place of fixed groove is fixedly installed with the clamping piece, the four edges of base plate vertical upwards extend and form the baffle, and the baffle is provided with the guide slot and is slidably installed with the locating plate, the locating plate still is equipped with the locating slot matched with PCB board on, the side wall surface of locating slot still is equipped with the elastic support piece, and the elastic support piece extends to the center direction of locating slot and is closely attached on the side wall surface of PCB board, the air bag body limiting structure is adopted in the present application, not only can utilize the unfolding of air bag body to push PCB board and carry out automatic calibration positioning to it, and in the clamping process, the side wall of PCB board is stressed evenly, especially when fixing the special-shaped plate, can avoid the special-shaped plate self -adaptation PCB board material's tolerance, compatible different batches of board material, still can eliminate the problem of stress concentration through the flexible contact, reduce the welding deformation, greatly improved the welding quality of PCB board.

Description

Technical Field

[0001] This utility model relates to the field of welding fixture technology, and specifically to a reflow soldering fixture. Background Technology

[0002] With the deepening application of intelligence, smart devices are becoming increasingly widely used. The motherboard is a core component of smart devices, and its manufacturing process requires surface mount technology (SMT) followed by reflow soldering. SMT is the most popular technology and process in the electronics assembly industry. It involves mounting leadless or short-lead surface mount components onto the surface of a printed circuit board or other substrate, and then soldering them using methods such as reflow soldering or dip soldering. Its characteristics include high assembly density and small electronic product size.

[0003] In current reflow soldering production processes, the PCB board is usually lifted and fixed on the fixture surface before soldering. This positioning method is mostly accomplished by mechanical limiting, such as pin fixing, slot guide rail and other structures. The positioning method mostly uses rigid connection, which can easily cause deformation, damage and positioning deviation in precision PCB soldering. Moreover, all of the above structures must use matching fixtures, which affects the production quality of the PCB board. Utility Model Content

[0004] Based on the above description, this utility model provides a reflow soldering fixture to solve the shortcomings of existing PCB board reflow soldering fixtures, which mostly use mechanical limiting methods for fixation. These methods are not only prone to deformation, damage, and positioning deviations, but also require matching fixtures, which can easily affect the production quality of PCB boards.

[0005] This utility model is achieved through the following technical solution:

[0006] A reflow soldering fixture includes a substrate. The top surface of the substrate has a fixing groove, and a clamping member is fixedly installed at the center of the fixing groove. The four sides of the substrate extend vertically upward to form a protective plate, and the protective plate has a guide groove and a positioning plate is slidably installed thereon. The positioning plate also has a positioning groove that matches the PCB board, and there is a gap between the inner wall of the positioning groove and the side wall of the PCB board. An elastic support member is also provided on the side wall of the positioning groove, and the elastic support member extends toward the center of the positioning groove and fits tightly against the side wall of the PCB board.

[0007] Furthermore, the clamping member is an electrically controlled suction cup, and the interior of the substrate is hollow and communicates with the fixing groove. The clamping member extends upward from the bottom of the substrate and the adsorption end extends through the fixing groove to a height flush with the surface of the substrate. A wiring port is also provided on the side wall of the substrate. One end of the wiring port is electrically connected to the clamping plate, and the other end of the wiring port is electrically connected to an external power supply circuit.

[0008] Furthermore, the positioning plate is provided with positioning holes at its four corners, and the bottom surface of the guide groove is provided with a locking groove that matches the positioning hole. The locking shaft inside the positioning hole extends downward and is inserted into the locking groove for locking and fixing.

[0009] Furthermore, the side wall of the locking shaft is provided with a mounting groove, and an arc-shaped block is provided in the mounting groove. One end of the arc-shaped block is movably hinged to the mounting groove, and the other end of the arc-shaped block is connected to a return spring. The return spring extends inward and is fixedly connected to the bottom surface of the mounting groove.

[0010] Furthermore, a limiting groove is provided on the side wall of the locking groove, and the inner side wall of the limiting groove is set to an arc shape. The locking shaft extends into the inside of the locking groove and causes the arc-shaped block to unfold outward into the limiting groove.

[0011] Furthermore, a spring rod is provided on the bottom surface of the locking groove, and the top end of the spring rod is in close contact with the bottom end of the locking shaft and applies upward thrust.

[0012] Furthermore, the elastic support is an airbag, and the outer wall of the positioning plate is also provided with an air supply hole, which is connected to the elastic support. The side wall of the substrate is provided with a through hole, and a connector is inserted into the through hole. One end of the connector is threaded to the air supply hole, and the other end of the connector is connected to an external air pipe.

[0013] Furthermore, the connector is also equipped with an electromagnetic valve and a pressure sensor, and both the electromagnetic valve and the pressure sensor are remotely connected to an external control center via a Bluetooth module or wire.

[0014] Compared with the prior art, the technical solution of this application has the following beneficial technical effects:

[0015] This application improves upon existing PCB reflow soldering fixtures by using an airbag to replace the traditional mechanical limiting structure. This not only allows the airbag to push the PCB board and automatically calibrate and position it, but also ensures uniform stress on the sidewalls of the PCB board during clamping. Especially when fixing irregularly shaped boards, it avoids the need for the irregularly shaped board to adapt to the tolerances of the PCB material, making it compatible with different batches of boards. In the subsequent heating and soldering process, it can also eliminate stress concentration through flexible contact and reduce soldering deformation through dynamic thermal expansion compensation, greatly improving the soldering quality of the PCB board. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the substrate, positioning plate, and PCB board in this embodiment;

[0017] Figure 2This is a schematic diagram of the structure when the locking shaft retracts in this embodiment;

[0018] Figure 3 This is a schematic diagram of the structure when the locking shaft is unfolded in this embodiment;

[0019] Figure 4 This is a schematic diagram of the locking shaft and locking groove in this embodiment;

[0020] Labels: 1. Base plate; 11. Fixing groove; 12. Protective plate; 13. Guide groove; 14. Locking groove; 15. Limiting groove; 16. Spring rod; 2. Positioning plate; 21. Positioning hole; 22. Locking shaft; 23. Mounting groove; 24. Arc block; 25. Return spring; 3. PCB board; 4. Clamping component; 5. Elastic support component. Detailed Implementation

[0021] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0023] Combination Figure 1-4 As shown, a reflow soldering fixture includes:

[0024] The base plate 1 serves as the mounting base for the entire fixture. It is designed as a rectangular structure and is fixedly mounted on the workbench with bolts. Its top surface is also provided with a fixing groove 11.

[0025] The clamping component 4 is set as an electrically controlled chuck, such as an electromagnetic chuck or a vacuum chuck, which is fixedly installed inside the substrate 1 and flush with the top surface of the substrate 1. It fixes the PCB board 3 on its surface by adsorption so that the PCB board 3 can be soldered in the future.

[0026] PCB board 3 is horizontally arranged on the top surface of substrate 1 and its surface is coated with solder paste for reflow soldering through subsequent heating;

[0027] Positioning plate 2 is set on substrate 1. It is used to initially position PCB board 3 through positioning groove on top that matches PCB board 3, so as to facilitate subsequent locking and fixing.

[0028] The elastic support 5 is set on the side wall of the positioning plate 2. It expands to squeeze the side wall of the PCB board 3, thereby quickly positioning it, preventing it from shaking, and enhancing the stability during the production process.

[0029] Specifically, in this embodiment, the interior of the substrate 1 is hollow, and a detachable cover plate is provided on the bottom surface. The clamping member 4 is disposed in the interior space of the substrate 1 and is fixed by the screw thread of the cover plate, so that the adsorption surface of the clamping member 4 is just engaged with the fixing groove 11 of the substrate 1. The purpose is to facilitate quick disassembly and maintenance when the suction cup fails.

[0030] In actual use, the clamping component 4 is mostly a vacuum chuck. If an electromagnetic chuck is used for fixing, metal pads should be added to the four sides of the corresponding PCB board 3 and special parts. The metal pads should be firmly locked to the PCB board 3 with screws to ensure that they can be effectively locked and fixed by magnetic attraction. It can also be used for welding other boards containing magnetic materials besides the PCB board 3.

[0031] The positioning plate 2 is also a rectangular structure with flanges at its four corners and positioning holes 21 on the flanges. A ball bearing is provided on the inner wall of the positioning hole 21, and a locking shaft 22 is movably sleeved through the inner ring of the ball bearing and the two are fixedly connected. The locking shaft 22 extends downward to the outside of the positioning plate 2 and has at least three mounting grooves 23 on its side wall. An arc-shaped block 24 is movably hinged in each mounting groove 23, and the other end of the arc-shaped block 24 is connected to a return spring 25. The return spring 25 extends into the mounting groove 23 and is fixedly connected to its bottom surface. Therefore, when the arc-shaped block 24 is squeezed, the return spring 25 will contract until the entire arc-shaped block 24 is contracted into the mounting groove 23.

[0032] In addition, protective plates 12 are provided on the four sides of the top surface of the substrate 1. Guide grooves 13 are provided on the inner sidewall of the protective plates 12. The positioning plate 2 is slidably assembled with the guide grooves 13 through the flange, so that the positioning plate 2 can be quickly fastened into the interior of the substrate 1 and the bottom surface of the positioning plate 2 is tightly fitted with the bottom surface of the fixing groove 11 to form a whole.

[0033] A locking groove 14 is also provided on the bottom surface of the guide groove 13. The locking groove 14 is set as a cylindrical structure, and a limiting groove 15 with an arc-shaped side wall is provided on its inner side wall. When the locking shaft 22 is inserted downward into the limiting groove 15, the arc-shaped block 24 is squeezed, causing the arc-shaped block 24 to retract into the mounting groove 23. At this time, the locking shaft 22 is twisted again to align the arc-shaped block 24 with the limiting groove 15. At this time, the return spring 25 will periodically turn the arc-shaped block 24 outward, so that it is locked into the limiting groove 15. If it needs to be disassembled, it is only necessary to continue to rotate the locking shaft 22 to make the arc-shaped block 24 be squeezed again and retract into the mounting groove 23, thereby quickly separating the entire positioning plate 2 from the base plate 1.

[0034] Furthermore, in order to compensate for the gap between the locking groove 14 and the locking shaft 22, an elastic pad should be provided on the bottom surface of the positioning plate 2. Then, a spring rod 16 is provided at the center of the bottom surface of the locking groove 14. The spring rod 16 can apply a pushing force to the locking shaft 22 through the telescopic end at the top. Therefore, when the arc block 24 is unfolded, it can be firmly fixed on the base plate 1 with the spring rod 16 to ensure that it will not easily shake.

[0035] In addition, the positioning groove located at the center of the positioning plate 2 has its inner wall fixedly connected to the elastic support member 5. The elastic support member 5 is an airbag, and the airbag is made of a high-temperature resistant elastic material, such as silicone rubber or fluororubber, to ensure that it can expand and be squeezed in a high-temperature environment. Furthermore, there should be multiple elastic support members 5, and the multiple airbags are interconnected.

[0036] After inflation, the airbag can adapt to the slight warping of the PCB board (≤1mm / m), filling the gaps through elastic deformation and ensuring uniform fixing force across the entire board. For example, when the PCB warps slightly during the preheating stage, the airbag can still maintain consistent pressure in all areas, while traditional clamps may experience localized loosening.

[0037] Airbags are evenly distributed along the edge of the PCB board (spacing ≤ 100mm), and auxiliary airbags are added in the center of gravity area to prevent the board from floating due to the impact of hot airflow during soldering. The surface of the silicone rubber airbags can be coated with PTFE to avoid flux residue causing the airbags to stick to the PCB and affect the board removal efficiency.

[0038] In the above structure, the airbag body can adapt to PCB boards 3 of different sizes and shapes (such as L-shaped and U-shaped boards) through modular design (such as array-type airbag groups), without the need for customized fixtures for each board type like mechanical clamps. For example, the same reflow soldering equipment can simultaneously process PCB boards 3 ranging from 50mm×50mm to 300mm×400mm by adjusting the airbag pressure. Moreover, it has good fixation for some special irregular parts. Compared with traditional metal clamps, the airbag body, through standardized modules and adjustable brackets, can cover more than 80% of board types, and the fixture cost is reduced by more than 50%.

[0039] The outer side wall of the positioning plate 2 is also provided with an air supply hole, which is connected to the elastic support 5. The side wall of the base plate 1 is provided with a through hole, and a metal connector is inserted into the through hole. One end of the connector is threaded to the air supply hole, and the other end of the connector is connected to the external air pipe. The connector is also provided with an electromagnetic valve and a pressure sensor. The electromagnetic valve (preferably Airtac 4V210-08) and the pressure sensor (preferably Minxin Micro MSPC01-GAD-F) are both remotely connected to the external control center via Bluetooth module or wire to work in coordination with the automated equipment.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of this utility model.

Claims

1. A reflow soldering fixture, characterized in that, The substrate (1) includes a fixing groove (11) on its top surface. A clamping member (4) is fixedly installed at the center of the fixing groove (11). The four sides of the substrate (1) extend vertically upward to form a protective plate (12). A guide groove (13) is provided on the protective plate (12) and a positioning plate (2) is slidably installed thereon. The positioning plate (2) is also provided with a positioning groove that matches the PCB board (3). A gap is left between the inner wall of the positioning groove and the side wall of the PCB board (3). An elastic support member (5) is also provided on the side wall of the positioning groove. The elastic support member (5) extends toward the center of the positioning groove and fits tightly against the side wall of the PCB board (3).

2. The reflow soldering fixture according to claim 1, characterized in that, The clamping member (4) is an electrically controlled suction cup, and the interior of the substrate (1) is hollow and communicates with the fixing groove (11). The clamping member (4) extends upward from the bottom of the substrate (1) and the adsorption end passes through the fixing groove (11) to a height flush with the surface of the substrate (1). A wiring port is also provided on the side wall of the substrate (1). One end of the wiring port is electrically connected to the clamping plate, and the other end of the wiring port is electrically connected to the external power supply circuit.

3. The reflow soldering fixture according to claim 2, characterized in that, The positioning plate (2) is provided with positioning holes (21) at its four corners, and the bottom surface of the guide groove (13) is provided with a locking groove (14) that matches the positioning hole (21). The locking shaft (22) inside the positioning hole (21) extends downward and is inserted into the locking groove (14) for locking and fixing.

4. The reflow soldering fixture according to claim 3, characterized in that, The locking shaft (22) has a mounting groove (23) on its side wall. An arc-shaped block (24) is provided in the mounting groove (23). One end of the arc-shaped block (24) is movably hinged to the mounting groove (23). The other end of the arc-shaped block (24) is connected to a return spring (25). The return spring (25) extends inward and is fixedly connected to the bottom surface of the mounting groove (23).

5. The reflow soldering fixture according to claim 4, characterized in that, The locking groove (14) is also provided with a limiting groove (15) on its side wall surface, and the inner side wall of the limiting groove (15) is set to be arc-shaped. The locking shaft (22) extends into the locking groove (14) and makes the arc-shaped block (24) unfold outward into the limiting groove (15).

6. The reflow soldering fixture according to claim 5, characterized in that, A spring rod (16) is also provided on the bottom surface of the locking groove (14). The top end of the spring rod (16) is closely attached to the bottom end of the locking shaft (22) and applies a thrust upward.

7. The reflow soldering fixture according to claim 6, characterized in that, The elastic support (5) is an airbag, and the outer side wall of the positioning plate (2) is also provided with an air supply hole. The air supply hole is connected to the elastic support (5). The side wall of the base plate (1) is provided with a through hole. A connector is inserted into the through hole. One end of the connector is threaded to the air supply hole, and the other end of the connector is connected to the external air pipe.

8. The reflow soldering fixture according to claim 7, characterized in that, The connector is also equipped with an electromagnetic valve and a pressure sensor, and both the electromagnetic valve and the pressure sensor are remotely connected to an external control center via a Bluetooth module or wire.

Images