PCB board fixing mechanism for tin paste detector

Abstract

The application discloses a PCB board fixing mechanism for a tin paste detector, and particularly relates to the technical field of PCB detection equipment, which comprises a tin paste detector and a pitch-adjustable conveying fixing mechanism. The tin paste detector comprises a rack, a detection assembly, a controller and the pitch-adjustable conveying fixing mechanism. The top end of the rack is fixedly connected with the pitch-adjustable conveying fixing mechanism. The top end of the pitch-adjustable conveying fixing mechanism is placed with the detection assembly. The side edge of the pitch-adjustable conveying fixing mechanism is fixedly connected with the controller. The first electric push rod drives the swing frame to adjust the inclination angle of the glass fiber tape, so that the reference edge of the PCB board is parallel to the coordinate system of the visual detector, and the measurement errors of the tin paste area, position and angle caused by the inclination of the PCB are reduced.

Description

Technical Field

[0001] This application relates to the field of PCB inspection equipment technology, and more specifically, to a PCB board fixing mechanism for a solder paste inspector. Background Technology

[0002] Surface mount technology (SMT) is one of the core processes in the electronics manufacturing industry, and the quality of solder paste printing directly determines the yield of subsequent component placement and soldering. Solder paste inspection machines use visual inspection technology to measure the area, thickness, position, and three-dimensional contour of solder paste on PCB boards, and are key equipment to ensure the quality of SMT production lines. Existing publication number CN121576958B discloses a PCB offset detection method, relating to the field of PCB inspection technology, including the following steps: S1, inputting a standard template; S2, acquiring an image of the terminal area of ​​the panel to be inspected and analyzing identifiable fixed technical features; S3, comparing the associated parameters of the fixed technical features with the parameters of the standard template and calculating the offset value; S4, determining whether the offset value is within the acceptable range; Simultaneously, the detection method supports PCB and FPC combinations with different terminal area features, and by calculating the offset values ​​in both the X and Y directions, it broadens the adaptability range while improving detection accuracy and reducing the false positive and false negative rates. In the process of realizing this application, the inventors discovered the following problems with the prior art: In existing systems, PCB boards are prone to angular displacement during transport, causing their reference edge to be non-parallel to the detection coordinate system, which in turn leads to measurement errors in solder paste area, position, and angle. Existing mechanisms mostly use rigid push plates for correction, which can easily scratch the edges of the PCB board. Furthermore, thin PCBs or PCBs that have undergone multiple reflow soldering processes are prone to warping. Existing rigid clamping mechanisms either cannot completely flatten the warped board to the detection reference plane, resulting in errors in solder paste thickness and three-dimensional contour measurement; or the clamping force is too large, causing permanent deformation or even damage to the PCB board.

[0003] Therefore, a PCB board fixing mechanism for a solder paste tester is proposed to address the above problems. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, this application provides a PCB board fixing mechanism for a solder paste tester to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this application provides the following technical solution: a PCB board fixing mechanism for a solder paste inspection instrument, comprising a solder paste inspection machine and a pitch-adjustable conveying and fixing mechanism. The solder paste inspection machine includes a frame, an inspection component, a controller, and a pitch-adjustable conveying and fixing mechanism. The top of the frame is fixedly connected to the pitch-adjustable conveying and fixing mechanism, the top of the pitch-adjustable conveying and fixing mechanism is equipped with an inspection component, and the side of the pitch-adjustable conveying and fixing mechanism is fixedly connected to the controller. The adjustable spacing conveying and fixing mechanism includes a mounting base, a lead screw conveying platform, and a conveying assembly. The lead screw conveying platform is fixedly connected to the top of the mounting base, and the conveying assembly is plugged into the lead screw conveying platform. The lead screw conveying platform includes a drive motor, a lead screw body, and a limiting plate. The drive end of the drive motor is connected to the lead screw body, and the end of the lead screw body is connected to the limiting plate through a bearing. The drive motor 11 drives the lead screw body 12 to rotate, thereby adjusting the spacing of the conveying assembly 10 to adapt to PCB boards of different widths.

[0006] Preferably, the conveying component includes an attitude correction component and a fixing component, and the bottom end of the attitude correction component is fixedly connected to the fixing component; The attitude correction component includes a first fixed bracket, a placement slot, a high-speed array camera, a laser triangulation displacement sensor array, a first correction component, and a magnetorheological limiting component. The first fixed bracket has a placement slot reserved in its inner cavity. The high-speed array camera is fixedly connected to the first fixed bracket directly above the PCB board being transported. The laser triangulation displacement sensor array is fixedly connected to the first fixed bracket on the side of the PCB board being transported. The first correction component is placed on the side of the laser triangulation displacement sensor array. The magnetorheological limiting component is placed on the side of the first correction component. The first correction component and the magnetorheological limiting component are fixedly connected to the first fixed bracket.

[0007] Preferably, the first correction component includes an assembly bracket, a connecting shaft, a swing frame, a first electric push rod, a quick-release collar, and a fiberglass tape. The top end of the assembly bracket is fixedly connected to the connecting shaft, and the connecting shaft is connected to the swing frame via a bearing sleeve. The pushing end of the swing frame is connected to the first electric push rod, and the swing end of the swing frame is fixedly connected to the quick-release collar. The clamping end of the quick-release collar is connected to the fiberglass tape. The fiberglass tape has the characteristics of high strength, high toughness, and smooth surface, which can provide sufficient correction thrust without scratching the edge of the PCB board. The quick-release collar 30 facilitates the quick replacement of the fiberglass tape.

[0008] Preferably, the magnetorheological limiting component includes a connecting block and a fluid placement shell. The bottom end of the connecting block is fixedly connected to the fluid placement shell, and the contact end of the fluid placement shell 40 is made of a flexible material. The fluid placement shell 40 is filled with magnetorheological fluid. The magnetorheological fluid is liquid when not energized, has good fluidity, and can completely conform to the warped surface of the PCB board; when energized, it instantly transforms into a solid state, providing a support surface that can be adjusted according to the movement of the PCB.

[0009] Preferably, the fixing component further includes a housing, a mounting plate, and a lifting groove. The mounting plate is fixedly connected to the inner cavity of the housing. The lifting groove is provided at the edge of the mounting plate. A servo motor is fixedly connected to the bottom end of the mounting plate. A belt is connected to the drive end of the servo motor. A connecting wheel is attached to the edge of the belt. A push plate is provided on the mounting plate directly above the magnetorheological limiting component.

[0010] Preferably, the push plate includes a push bracket, and a second fixed bracket is fixedly connected to the top of the push bracket. The top of the second fixed bracket is provided with two sets of fixed heads, which are located on both sides of the belt. A lifting rod is fixedly connected to the edge of the fixed head. The second fixed bracket is pushed by an electric push rod provided on the push bracket to achieve lifting and lowering, thereby driving the push plate to lift and lower.

[0011] Preferably, the detection component includes a vision inspection instrument and a cross-shaped horizontal slide. The vision inspection instrument is fixedly connected to the top of the cross-shaped horizontal slide. The cross-shaped horizontal slide is fixedly connected to the frame. The cross-shaped horizontal slide can drive the vision inspection instrument to move in the X and Y directions to achieve scanning and detection of the entire area of ​​the PCB board.

[0012] Preferably, the solder paste testing machine is as follows: The controller is electrically connected to the high-speed array camera, the laser triangulation displacement sensor array, the first correction component, the magnetorheological limit component, the servo motor, the drive motor, the vision inspection instrument, and the cross horizontal slide table. The high-speed array camera is used to collect the deflection angle, edge contour and planar size data of the PCB board and send them to the controller. The controller controls the first electric push rod to drive the swing frame to swing according to the deflection angle data, so as to adjust the tilt angle of the glass fiber tape, so that the reference edge of the PCB board is parallel to the detection coordinate system of the vision inspection instrument, and eliminates the measurement error of solder paste area, position and angle caused by PCB tilt. The laser triangular displacement sensor array is used to collect data on the thickness, warpage, and surface height distribution of the PCB board and send them to the controller. The controller controls the push bracket to drive the push plate to rise along the lifting groove according to the thickness and warpage data, so that the PCB board is evenly pressed into the flexible contact end of the magnetorheological limiting component at a preset depth. Then, the controller controls the magnetorheological limiting component to be energized and hardened, fixing the PCB board on the detection reference plane without deformation, eliminating the measurement error of solder paste thickness and three-dimensional contour caused by PCB warpage and displacement. Finally, the controller controls the vision inspection instrument to move along the cross horizontal slide to complete the solder paste inspection.

[0013] The technical effects and advantages of this application are as follows: 1. Compared with the prior art, the PCB board fixing mechanism of this solder paste inspection instrument uses a high-speed array camera to collect the deflection angle, edge contour and planar dimension data of the PCB board. It is combined with the flexible contact correction structure of the glass fiber tape of the first correction component. Because the glass fiber tape has the characteristics of high strength, high toughness and smooth surface, it can provide a stable correction thrust and completely avoid the scratching and chipping of the PCB board edge caused by the traditional rigid push plate. The tilt angle of the glass fiber tape is adjusted by driving the swing frame through the first electric push rod, so that the reference edge of the PCB board is parallel to the detection coordinate system of the vision inspection instrument, reducing the measurement error of solder paste area, position and angle caused by PCB tilt.

[0014] 2. Compared with the prior art, the PCB board fixing mechanism of this solder paste inspection instrument adopts a magnetorheological limiting component combined with a laser triangular displacement sensor array. The laser triangular displacement sensor array can collect data on the thickness, warpage and surface height distribution of the PCB board in real time. The controller controls the lifting height of the push plate accordingly, so that the PCB board is uniformly pressed into the flexible contact end of the magnetorheological limiting component at a preset depth. The magnetorheological fluid is in a liquid state when not energized, which can completely conform to the warped surface of the PCB board. After being energized, it hardens in milliseconds to form a rigid support surface that perfectly matches the PCB contour. This eliminates the need to apply excessive clamping force and fixes the PCB board on the inspection reference plane without deformation. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of this application; Figure 2 This is a schematic diagram of the adjustable-spacing conveying and fixing mechanism of this application; Figure 3 This is a top view of the adjustable-spacing conveying and fixing mechanism of this application. Figure 4 This is a schematic diagram of the structure of the delivery component of this application; Figure 5 This is a schematic diagram of the unfolded structure of the delivery component of this application; Figure 6 This is a schematic diagram of the posture correction component of this application; Figure 7This is a top view of the posture correction component of this application. Figure 8 This is a first-view structural diagram of the first corrective component of this application; Figure 9 This is a schematic diagram of the second-view structure of the first corrective component of this application; Figure 10 This is a third-view structural diagram of the first corrective component of this application; Figure 11 This is a schematic diagram of the unfolded structure of the fixed component of this application; Figure 12 This is a first-view structural diagram of the push plate of this application; Figure 13 This is a schematic diagram of the second-view structure of the push plate in this application; Figure 14 This is a schematic diagram of the unfolded structure of the magnetorheological limiting component of this application; Figure 15 This is a schematic diagram of the magnetorheological limiting component of this application.

[0016] The attached figures are labeled as follows: 1. Solder paste inspection machine; 2. Frame; 3. Inspection component; 4. Vision inspection instrument; 5. Cross-shaped horizontal slide; 6. Controller; 7. Adjustable spacing conveying and fixing mechanism; 8. Mounting base; 9. Lead screw conveying platform; 10. Conveying component; 11. Drive motor; 12. Lead screw body; 13. Limit plate; 14. Posture correction component; 15. Fixing component; 16. Servo motor; 17. Belt; 18. Connecting wheel; 19. Push plate; 20. First fixed bracket; 1. Placement slot; 22. High-speed array camera; 23. Laser triangulation displacement sensor array; 24. First correction component; 25. Magnetorheological limiting component; 26. Assembly bracket; 27. Connecting shaft; 28. Swing frame; 29. ​​First electric push rod; 30. Quick-release collar; 31. Fiberglass tape; 32. Housing; 33. Mounting plate; 34. Lifting slot; 35. Push bracket; 36. Second fixed bracket; 37. Lifting rod; 38. Fixed head; 39. Connecting block; 40. Fluid placement shell. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0018] Example As attached Figures 1 to 15A PCB board fixing mechanism for a solder paste detector as shown, comprising a solder paste detector 1 and a conveying and fixing mechanism 7 with adjustable spacing, wherein the solder paste detector 1 is composed of a frame 2, a detection assembly 3, a controller 6 and the conveying and fixing mechanism 7 with adjustable spacing, the top end of the frame 2 is fixedly connected with the conveying and fixing mechanism 7 with adjustable spacing, the detection assembly 3 is placed at the top end of the conveying and fixing mechanism 7 with adjustable spacing, the side of the conveying and fixing mechanism 7 with adjustable spacing is fixedly connected with the controller 6, the controller 6 is specifically a PLC controller 6, which is fixed on the side of the conveying and fixing mechanism 7 with adjustable spacing and has the capabilities of high-speed data processing and multi-axis linkage control; The conveying and fixing mechanism 7 with adjustable spacing comprises a mounting base 8, a screw conveying platform 9 and a conveying assembly 10, the mounting base 8 is a steel plate welded structure and is fixed on the frame 2 through bolts, the screw conveying platform 9 comprises a driving motor 11, a screw main body 12 and a limiting plate 13, the driving end of the driving motor 11 is connected with the screw main body 12, the end of the screw main body 12 is connected with the limiting plate 13 through a bearing, the screw conveying platform 9 is fixed at the top end of the mounting base 8 and is composed of the driving motor 11, the screw main body 12 and the limiting plate 13, the driving motor 11 adopts a stepping motor, the screw main body 12 is a ball screw, the conveying assembly 10 is inserted onto the screw conveying platform 9, the driving motor 11 drives the screw main body 12 to rotate, which can drive the conveying assembly 10 to move along the axial direction of the screw to adjust the spacing between two groups of conveying assemblies 10, so as to adapt to PCB boards with different widths.

[0019] As a preferred embodiment, the conveying assembly 10 comprises a posture correction assembly 14 and a fixing assembly 15, and the bottom end of the posture correction assembly 14 is fixedly connected with the fixing assembly 15; The posture correction assembly 14 comprises a first fixing bracket 20, a placement groove 21, a high-speed array camera 22, a laser triangular displacement sensor array 23, a first correction assembly 24 and a magnetorheological limiting assembly 25, the first fixing bracket 20 is in an inverted L-shaped structure, a conveying channel for accommodating a PCB board is reserved in the inner cavity of the first fixing bracket 20, the first fixing bracket 20 is located directly above the PCB board conveying path and is fixedly connected with the high-speed array camera 22, the high-speed array camera 22 adopts a global shutter camera and is installed at the top center of the first fixing bracket 20, facing the upper surface of the conveyed PCB board, the first fixing bracket 20 is located at the side of the conveyed PCB board and is fixedly connected with the laser triangular displacement sensor array 23, the laser triangular displacement sensor array 23 is composed of 8 laser displacement sensors, which are arranged at equal intervals along the width direction of the PCB board, the first correction assembly 24 is placed at the side of the laser triangular displacement sensor array 23, the magnetorheological limiting assembly 25 is placed at the side of the first correction assembly 24, and the first correction assembly 24 and the magnetorheological limiting assembly 25 are fixedly connected with the first fixing bracket 20.

[0020] In a preferred embodiment, the first correction component 24 includes an assembly bracket 26, a connecting shaft 27, a swing frame 28, a first electric push rod 29, a quick-release collar 30, and a fiberglass tape 31. The assembly bracket 26 of the first correction component 24 is fixed on the first fixed bracket 20. The connecting shaft 27 is vertically fixed to the top of the assembly bracket 26. The swing frame 28 is sleeved on the connecting shaft 27 through a bearing and can swing freely around the connecting shaft 27. The first electric push rod 29 is fixed on the assembly bracket 26, and its driving end is hinged to the pushing end of the swing frame 28. The swing frame 28 is driven to swing by the extension and retraction of the first electric push rod 29. The swing end of the swing frame 28 is fixed with a quick-release collar 30. The fiberglass tape 31 is clamped at the clamping end of the quick-release collar 30. The fiberglass tape 31 has a width of 10 mm, a thickness of 0.5 mm, and a polished surface.

[0021] In a preferred embodiment, the magnetorheological limiting component 25 includes a connecting block 39 and a fluid placement shell 40. The bottom end of the connecting block 39 is fixedly connected to the fluid placement shell 40, which is made of silicone material and filled with magnetorheological fluid. The contact end is arc-shaped to better fit the edge of the PCB board. An electromagnetic coil is integrated inside the fluid placement shell 40, which generates a magnetic field when energized, causing the magnetorheological fluid to harden.

[0022] In a preferred embodiment, the fixing component 15 further includes a housing 32, a mounting plate 33, and a lifting groove 34. The mounting plate 33 is fixedly connected to the inner cavity of the housing 32, and the lifting groove 34 is provided at the edge of the mounting plate 33.

[0023] In a preferred embodiment, a servo motor 16 is fixedly connected to the bottom end of the mounting plate 33, a belt 17 is connected to the drive end of the servo motor 16, and a connecting wheel 18 is attached to the edge of the belt 17. The belt 17 meshes with the four connecting wheels 18 for transmission. A push plate 19 is provided on the mounting plate 33 directly above the magnetorheological limiting assembly 25.

[0024] In a preferred embodiment, the push plate 19 includes a push bracket 35, with a second fixed bracket 36 fixedly connected to the top of the push bracket 35. Two sets of fixed heads 38 are provided at the top of the second fixed bracket 36, located on both sides of the belt 17. Lifting rods 37 are fixedly connected to the edges of the fixed heads 38. The push plate 19 is equipped with a push bracket 35, and the second fixed bracket 36 is pushed and lifted by an electric push rod provided on the push bracket 35. Since the top of the second fixed bracket 36 has two sets of fixed heads 38 located on both sides of the belt 17, when the PCB board moves to this area, the push bracket 35 pushes the second fixed bracket 36 upwards, and the two sets of fixed heads 38 push the PCB board into contact with the magnetorheological limiting component 25. Based on the detected data, the lifting rod 37 at the bottom of the PCB board remains stationary. After detection, the lifting rod 37 behind the PCB board rises and squeezes the magnetorheological limiting component 25, allowing the PCB board to quickly detach, thus facilitating the transport of the PCB board away.

[0025] In a preferred embodiment, the detection assembly 3 includes a vision inspection instrument 4 and a cross-shaped horizontal slide 5. The top of the cross-shaped horizontal slide 5 is fixedly connected to the vision inspection instrument 4, and the cross-shaped horizontal slide 5 is fixedly connected to the frame 2.

[0026] As a preferred embodiment, the solder paste inspection machine 1: The controller 6 is electrically connected to the high-speed array camera 22, the laser triangulation displacement sensor array 23, the first correction component 24, the magnetorheological limit component 25, the servo motor 16, the drive motor 11, the vision inspection instrument 4, and the cross horizontal slide 5, respectively. The high-speed array camera 22 is used to collect the deflection angle, edge contour and planar dimension data of the PCB board and send them to the controller 6. The controller 6 controls the first electric push rod 29 to drive the swing frame 28 to swing according to the deflection angle data, so as to adjust the tilt angle of the glass fiber tape 31, so that the reference edge of the PCB board is parallel to the detection coordinate system of the vision inspection instrument 4, and eliminates the measurement error of solder paste area, position and angle caused by PCB tilt. The laser triangular displacement sensor array 23 is used to collect data on the thickness, warpage, and surface height distribution of the PCB board and send them to the controller 6; The controller 6 controls the push bracket to drive the push plate 19 to rise along the lifting groove 34 according to the thickness and warpage data, so that the PCB board is evenly pressed into the flexible contact end of the magnetorheological limiting component 25 at a preset depth. Then, the controller 6 controls the magnetorheological limiting component 25 to be energized and hardened, fixing the PCB board on the detection reference plane without deformation, eliminating the measurement error of solder paste thickness and three-dimensional contour caused by PCB warpage and displacement. Finally, the controller 6 controls the vision inspection instrument 4 to move along the cross horizontal slide 5 to complete the solder paste inspection.

[0027] The working process of this application is as follows: First, according to the width and thickness of the PCB board to be tested, the corresponding parameters are preset in the controller 6. The controller 6 controls the drive motor 11 to rotate, which drives the lead screw body 12 to rotate, and adjusts the distance between the two sets of conveying components 10 to the preset value. The PCB board to be inspected is fed into the conveyor belt 17 of the conveyor assembly 10 by the feeding mechanism, and the conveyor belt 17 drives the PCB board to move towards the inspection station; When the PCB board moves directly below the high-speed array camera 22, the high-speed array camera 22 acquires an image of the PCB board and sends it to the controller 6. The controller 6 calculates the deflection angle, edge contour, and planar dimensions of the PCB board using an image processing algorithm. The PCB board continues to move below the laser triangulation sensor array 23, which acquires the height data of the PCB board surface and sends it to the controller 6. The controller 6 then calculates the thickness, warpage, and surface height distribution of the PCB board. According to the calculated deflection angle, the controller 6 controls the extension and retraction of the first electric push rod 29, drives the swing frame 28 to swing around the connecting shaft 27 by a corresponding angle, so that the tilt angle of the fiberglass tape 31 matches the deflection angle of the PCB board. The fiberglass tape 31 and the edge contour of the PCB board push the PCB board to rotate until the reference edge of the PCB board is parallel to the detection coordinate system of the vision inspection instrument 4, thus completing the posture correction. After the posture correction is completed, the controller 6 calculates the lifting height of the push plate 19 based on the thickness and warpage data of the PCB board, and controls the servo motor 16 to rotate. Its second fixed bracket 36 is pushed by the electric push rod set on the push bracket 35 to achieve lifting and lowering. The fixed head 38 of the push plate 19 lifts the PCB board up, so that the two sides of the PCB board are evenly pressed into the flexible contact end of the magnetorheological limiting component 25 at a preset depth. At this time, the magnetorheological fluid is in a liquid state and can completely conform to the warped surface of the PCB board. After reaching the preset lifting height, the controller 6 controls the electromagnetic coil of the magnetorheological limiting component 25 to be energized, and the magnetorheological fluid hardens instantly, fixing the PCB board on the detection reference plane without deformation.

[0028] After the PCB board is fixed, the controller 6 controls the cross-shaped horizontal slide 5 to move the vision inspection instrument 4 to scan and inspect all solder paste points on the PCB board, obtain data such as the area, thickness, three-dimensional contour and position of the solder paste, and compare it with standard data to judge the solder paste printing quality.

[0029] After the test is completed, the controller 6 de-energizes the magnetorheological limit component 25, and the magnetorheological fluid returns to a liquid state. The servo motor 16 reverses, driving the push plate 19 to descend, and the PCB board falls back onto the belt 17. The belt 17 then carries the PCB board out of the testing station, completing the entire testing process. The above describes the working principle of the PCB board fixing mechanism of this solder paste tester.

Claims

1. A PCB board fixing mechanism for a solder paste inspector, comprising a solder paste inspector (1) and an adjustable-pitch conveying and fixing mechanism (7), characterized in that: The solder paste testing machine (1) includes a frame (2), a testing component (3), a controller (6) and a pitch-adjustable conveying and fixing mechanism (7). The top of the frame (2) is fixedly connected to the pitch-adjustable conveying and fixing mechanism (7), the top of the pitch-adjustable conveying and fixing mechanism (7) is where the testing component (3) is placed, and the side of the pitch-adjustable conveying and fixing mechanism (7) is fixedly connected to the controller (6). The adjustable spacing conveying and fixing mechanism (7) includes a mounting base (8), a screw conveying platform (9) and a conveying assembly (10). The top of the mounting base (8) is fixedly connected to the screw conveying platform (9), and the screw conveying platform (9) is plugged into the conveying assembly (10).

2. The PCB board fixing mechanism for a solder paste detector according to claim 1, characterized in that: The conveying assembly (10) includes an attitude correction assembly (14) and a fixing assembly (15), with the fixing assembly (15) fixedly connected to the bottom end of the attitude correction assembly (14). The attitude correction component (14) includes a first fixed bracket (20), a placement slot (21), a high-speed array camera (22), a laser triangulation sensor array (23), a first correction component (24), and a magnetorheological limiting component (25). The inner cavity of the first fixed bracket (20) is reserved with a placement slot (21). The high-speed array camera (22) is fixedly connected to the first fixed bracket (20) directly above the PCB board being transported. The laser triangulation sensor array (23) is fixedly connected to the side of the first fixed bracket (20) being transported. The first correction component (24) is placed on the side of the laser triangulation sensor array (23). The magnetorheological limiting component (25) is placed on the side of the first correction component (24). The first correction component (24) and the magnetorheological limiting component (25) are fixedly connected to the first fixed bracket (20).

3. The PCB board fixing mechanism for a solder paste detector according to claim 2, characterized in that: The first correction component (24) also includes an assembly bracket (26), a connecting shaft (27), a swing frame (28), a first electric push rod (29), a quick-release collar (30), and a fiberglass tape (31). The top end of the assembly bracket (26) is fixedly connected to the connecting shaft (27). The connecting shaft (27) is connected to the swing frame (28) through a bearing sleeve. The pushing end of the swing frame (28) is connected to the first electric push rod (29). The swing end of the swing frame (28) is fixedly connected to the quick-release collar (30). The clamping end of the quick-release collar (30) is connected to the fiberglass tape (31).

4. The PCB board fixing mechanism for a solder paste detector according to claim 2, characterized in that: The magnetorheological limiting component (25) includes a connecting block (39) and a fluid placement shell (40). The bottom end of the connecting block (39) is fixedly connected to the fluid placement shell (40), and the contact end of the fluid placement shell (40) is made of a flexible material.

5. The PCB board fixing mechanism for a solder paste detector according to claim 2, characterized in that: The fixing component (15) also includes a housing (32), a mounting plate (33) and a lifting groove (34). The mounting plate (33) is fixedly connected to the inner cavity of the housing (32), and the lifting groove (34) is provided at the edge of the mounting plate (33).

6. The PCB board fixing mechanism for a solder paste detector according to claim 5, characterized in that: A servo motor (16) is fixedly connected to the bottom end of the mounting plate (33), and a belt (17) is connected to the drive end of the servo motor (16). A connecting wheel (18) is attached to the edge of the belt (17), and a push plate (19) is provided on the mounting plate (33) directly above the magnetorheological limiting component (25).

7. The PCB board fixing mechanism for a solder paste detector according to claim 1, characterized in that: The lead screw conveying platform (9) includes a drive motor (11), a lead screw body (12) and a limiting plate (13). The drive end of the drive motor (11) is connected to the lead screw body (12), and the end of the lead screw body (12) is connected to the limiting plate (13) through a bearing.

8. The PCB board fixing mechanism for a solder paste detector according to claim 6, characterized in that: The push plate (19) includes a push bracket (35), and a second fixed bracket (36) is fixedly connected to the top of the push bracket (35). The top of the second fixed bracket (36) is provided with two sets of fixed heads (38). The fixed heads (38) are located on both sides of the belt (17), and a lifting rod (37) is fixedly connected to the edge of the fixed head (38).

9. The PCB board fixing mechanism for a solder paste detector according to claim 1, characterized in that: The detection component (3) includes a vision inspection instrument (4) and a cross-shaped horizontal slide (5). The vision inspection instrument (4) is fixedly connected to the top of the cross-shaped horizontal slide (5). The cross-shaped horizontal slide (5) and the frame (2) are fixedly connected.

10. A PCB board fixing mechanism for a solder paste detector according to any one of claims 1-9, characterized in that: The solder paste inspection machine (1): The controller (6) is electrically connected to the high-speed array camera (22), the laser triangular displacement sensor array (23), the first correction component (24), the magnetorheological limit component (25), the servo motor (16), the drive motor (11), the vision inspection instrument (4) and the cross horizontal slide (5); The high-speed array camera (22) is used to collect the deflection angle, edge contour and planar size data of the PCB board and send them to the controller (6). The controller (6) controls the first electric push rod (29) to drive the swing frame (28) to swing according to the deflection angle data, so as to adjust the tilt angle of the glass fiber tape (31) and make the reference edge of the PCB board parallel to the detection coordinate system of the vision inspection instrument (4), thereby eliminating the measurement error of solder paste area, position and angle caused by PCB tilt. The laser triangular displacement sensor array (23) is used to collect the thickness, warpage and surface height distribution data of the PCB board and send them to the controller (6). The controller (6) controls the push bracket to drive the push plate (19) to rise along the lifting groove (34) according to the thickness and warpage data, so that the PCB board is pressed into the flexible contact end of the magnetorheological limiting component (25) at a preset depth. Then the controller (6) controls the magnetorheological limiting component (25) to be energized and hardened, so that the PCB board is fixed on the detection reference plane without deformation, eliminating the measurement error of solder paste thickness and three-dimensional contour caused by PCB warpage and displacement. Finally, the controller (6) controls the vision inspection instrument (4) to move along the cross horizontal slide (5) to complete the solder paste inspection.

Images