A SMT surface mount reflow process

Abstract

The invention discloses an SMT surface mount reflow soldering process, and the invention relates to the technical field of SMT surface mount and reflow soldering processing. The SMT surface mount reflow soldering processing is completed by the cooperation of a detection platform, a bearing shaft, an annular disk, a self-clamping mechanism, a double-sided visual inspection mechanism, an intermittent position adjustment linkage part and an alignment matching part. The middle part of the upper end surface of the detection platform is rotatably connected with the bearing shaft, and an alignment matching part for maintaining the stability of the detection position is installed between the double-sided visual inspection mechanism and the annular disk. The invention ensures synchronous shooting of the front and back sides through synchronous visual shooting of the upper and lower surfaces, multi-station rotation shooting detection, multi-station rapid clamping limit and linkage of the alignment matching part, avoids missed detection and false detection, and the multi-station design improves the detection efficiency, and the rapid clamping limit reduces the manual operation time, improves the accuracy and consistency, and ensures the shooting stability and accuracy of the detection position adjustment limit, reduces errors and damage, and realizes comprehensive, efficient and high-precision detection.

Description

Technical Field

[0001] The invention relates to the technical field of SMT surface mounting and reflow soldering processing, in particular to an SMT surface mounting reflow soldering process. Background Art

[0002] SMT surface mounting technology and reflow soldering technology are extremely critical processes in the modern electronic manufacturing industry, especially in the assembly process of PCB circuit boards. They have the advantages of high precision, high-density assembly, high welding quality, high production efficiency, and easy maintenance and repair. The existing SMT surface mounting reflow soldering process mainly includes solder paste printing, patch operation, reflow soldering operation, cooling and quality inspection. Among them, quality inspection is one of the most important steps. The quality inspection of PCB circuit boards after reflow soldering is generally carried out by visual quality inspection through CCD cameras. CCD cameras can capture high-resolution images and cooperate with special image processing software to identify and analyze solder joint quality defects and component assembly defects on PCB circuit boards.

[0003] However, existing visual inspection equipment can usually only perform single-sided inspection, and defects on the other side (such as solder joint problems, short circuits, open circuits, etc.) cannot be discovered in time. The PCB needs to be flipped to inspect the other side, which increases the inspection time. The flipping process may cause the PCB to shift or be damaged, increasing the risk of inspection errors or missed inspections. After flipping, the position and angle of each PCB may be slightly different, affecting the consistency and reliability of the inspection results.

[0004] In addition, the existing detection requires additional clamping and limiting operations after the PCB circuit board is placed. Manual clamping and limiting require additional time, which affects the detection speed. Summary of the invention

[0005] The present invention provides an SMT surface mount reflow soldering process, which solves the problem that existing visual inspection equipment can usually only inspect one side and cannot inspect defects on the other side at the same time, and needs to flip the PCB circuit board, which not only increases the inspection time, but also may cause the circuit board to shift or be damaged, increase the inspection error and the risk of missed inspection, and affect the consistency and reliability of the inspection results. After the circuit board is placed, additional manual clamping and limiting operations are required, which further reduces the technical problem of inspection speed and production efficiency.

[0006] The present invention provides an SMT surface mount reflow soldering process, and the specific SMT surface mount reflow soldering process steps are as follows:

[0007] S1. Solder paste printing: Print a thin layer of solder paste on the pad of the PCB circuit board.

[0008] S2. SMT operation: Use a precision SMT machine to place SMT components on the pre-printed solder paste position on the PCB circuit board for SMT operation.

[0009] S3, reflow soldering operation: put the PCB circuit board with SMT components into the reflow soldering furnace for reflow soldering operation.

[0010] S4, cooling and curing: Cool and cure the PCB after reflow soldering to make the SMT components completely fixed on the PCB.

[0011] S5. Quality inspection: After cooling and curing, the PCB circuit boards are placed into the self-clamping mechanism for limiting, and then the quality is inspected by the double-sided visual inspection mechanism.

[0012] The SMT surface mount reflow process steps in the above steps S1-S5 need to be completed by the cooperation of the inspection table, the bearing shaft, the annular disk, the self-clamping mechanism, the double-sided visual inspection mechanism, the intermittent positioning linkage part and the alignment coordination part.

[0013] A load-bearing shaft is rotatably connected to the middle of the upper end surface of the detection platform, an annular disk is fixedly connected to the outside of the load-bearing shaft, and a plurality of self-clamping mechanisms for quickly limiting the PCB circuit board are equidistantly arranged on the annular disk in the circumferential direction; a double-sided visual inspection mechanism for simultaneously visually inspecting both sides of the PCB circuit board is arranged on the upper end surface of the detection platform; an intermittent positioning linkage part for intermittently rotating the annular disk to adjust the position of the self-clamping mechanism is installed between the double-sided visual inspection mechanism and the load-bearing shaft; a positioning matching part for maintaining the stability of the inspection position is installed between the double-sided visual inspection mechanism and the annular disk.

[0014] In a possible implementation, the self-clamping mechanism includes a rectangular mounting through slot provided on the annular disk, a U-shaped rectangular frame being fixedly connected to the rectangular mounting through slot via a fixing rod, a transparent plate being embedded and fixedly connected in the U-shaped rectangular frame, a rotating shaft being rotatably connected to the vertical section of the U-shaped rectangular frame, a torsion spring being fixedly connected between the rotating shaft and the U-shaped rectangular frame, an L-shaped clamping plate being fixedly connected to the outside of the rotating shaft, supporting claws being fixedly connected to the lower part of the L-shaped clamping plate at equal intervals, a plurality of strip through slots corresponding to the supporting claws being equidistantly provided on the U-shaped rectangular frame, two triggering components corresponding to the L-shaped clamping plate and used for driving the L-shaped clamping plate to rotate and clamp the PCB circuit board are symmetrically arranged on the transverse section of the U-shaped rectangular frame, and a tightening component for further clamping the L-shaped clamping plate to the PCB circuit board is installed between the two rotating shafts and the rectangular mounting through slots.

[0015] In a possible implementation, the touch assembly includes two strip grooves symmetrically opened on the side end surfaces of the transverse section of the U-shaped rectangular mounting frame, a sliding column is slidably connected in the strip groove, a push frame for cooperating with the support claw is fixedly connected between the two sliding columns, and a sliding groove corresponding to and connected to the strip groove is symmetrically opened on the upper end surface of the transverse section of the U-shaped rectangular frame, and an inclined pressure plate that abuts against the outside of the sliding column is hinged in the sliding groove.

[0016] In one possible implementation, the clamping assembly includes a gear fixedly connected to the same side end of the rotating shaft, the side groove wall of the rectangular mounting groove is slidably connected to a strip slide through a sliding sleeve, the side end surface of the strip slide is rotationally symmetrically fixedly connected to two racks respectively meshing with the gears, the groove wall of the rectangular mounting groove on one side close to the strip slide is hinged with a strip frame, the upper end surface of the strip frame is fixedly connected to a counterweight block, and the side of the strip slide close to the strip frame is fixedly connected to a shifting post slidably connected to the strip frame.

[0017] In a possible implementation, the double-sided visual inspection mechanism includes an L-shaped plate fixedly connected to the end surface of the inspection table, a bidirectional reciprocating electric telescopic rod is embedded and fixedly connected in the transverse section of the L-shaped plate, and a mounting frame is fixedly connected to the end of the bidirectional reciprocating electric telescopic rod. Visual inspection heads are provided in both mounting frames, and a ring-shaped fill light is fixedly connected to the side of the mounting frame close to the annular disk through a connecting rod.

[0018] In one possible implementation, the alignment and matching part includes a plurality of groups of Y-shaped alignment frame groups that are circumferentially equidistantly fixedly connected to the upper end surface of the annular disk and correspond to the rectangular mounting grooves. The mounting frame located at the upper part is symmetrically fixedly connected to the Y-shaped alignment frame group through fixed columns.

[0019] In a possible implementation, the intermittent positioning linkage part includes an annular reel rotatably connected to the upper end surface of the detection platform and sleeved on the outside of the load-bearing shaft, the annular reel and the detection platform are fixedly connected with a reset torsion spring, the circumferential outer wall of the load-bearing shaft is equidistantly provided with a plurality of slots, the circumferential inner wall of the annular reel is fixedly connected with an elastic paddle that cooperates with the slots, a cable is wound around the annular reel, and the end of the cable away from the annular reel is fixedly connected to the upper end surface of the detection platform through a connecting block, the lower end surface of the mounting frame located at the lower part is fixedly connected with a push rod that cooperates with the cable, an empty slot is provided on the upper end surface of the detection platform and directly below the push rod, and a cable guide wheel is rotatably connected to the upper end surface of the detection platform and at the rear of the empty slot through a support plate.

[0020] In a possible implementation, an annular groove is provided on the outside of the bearing shaft, and a number of hemispherical grooves corresponding to the rectangular mounting grooves are equidistantly provided on the annular groove. The upper end surface of the detection platform is fixedly connected to a spring telescopic column that contacts the annular groove through a vertical plate.

[0021] It can be seen from the above technical solutions that the present invention has the following advantages:

[0022] 1) In the present invention, the front and back sides of the PCB circuit board can be detected at the same time, avoiding displacement or damage of the circuit board during the flipping process, reducing detection errors and the risk of missed detection, ensuring that the position and angle of each circuit board during the detection process are consistent, and improving the consistency and reliability of the detection results.

[0023] 2) In the present invention, the deadweight of the PCB circuit board is used to press down the trigger component to trigger the L-shaped clamp to automatically clamp and limit it, eliminating additional manual clamping operations, simplifying the entire detection process, ensuring the stability of the circuit board during the detection process, reducing position shift and clamping errors, and improving the accuracy of detection.

[0024] 3) In the present invention, the double-sided visual inspection mechanism can be designed with linkage design to immediately drive the annular disk to rotate and move the next circuit board to the inspection position after the inspection of one circuit board is completed, thereby realizing continuous operation and improving the inspection efficiency. At the same time, it also reduces the number of driving sources used. The linkage design ensures the synchronization of the inspection process, making the operation of different parts more coordinated and improving the accuracy of the inspection.

[0025] 4) In the present invention, during the PCB circuit board detection process, the combination of the alignment rod and the Y-shaped alignment frame group is used to automatically adjust and limit the detection position, so that the position of the PCB circuit board during detection is located directly below the detection point, which can ensure the accurate positioning of the circuit board for each detection, reduce the detection error, reduce the false alarm rate, and improve the accuracy and stability of the detection.

[0026] 5) In the present invention, through the mutual linkage between the above steps 1, 2, 3 and 4, the synchronous shooting of the front and back sides is ensured, and missed detection and false detection are avoided. The multi-station design can significantly improve the detection speed and efficiency. The fast clamping limit reduces the manual operation time, improves the accuracy and consistency of the detection, and can also ensure the stability and accuracy of the position during detection, reduce errors and damage, improve the reliability of detection, and realize comprehensive, efficient and high-precision detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0028] Figure 1This is a SMT surface mount reflow soldering process diagram provided by the present invention.

[0029] Figure 2 The present invention provides an overall structural diagram.

[0030] Figure 3 The present invention provides Figure 2 Schematic diagram of the enlarged structure of part A in FIG.

[0031] Figure 4 This is a schematic diagram of the cross-sectional structure of the self-clamping mechanism provided by the present invention.

[0032] Figure 5 This is a schematic diagram of the installation structure of the self-clamping mechanism provided by the present invention when viewed from above.

[0033] Figure 6 This is a schematic diagram of the structure of the self-clamping mechanism provided by the present invention from a side view perspective.

[0034] Figure 7 This is a schematic cross-sectional structural diagram of a trigger assembly provided by the present invention.

[0035] Figure 8 This is a schematic diagram of the installation structure of the intermittent position adjustment linkage part provided by the present invention.

[0036] Fig. 9 The present invention provides Figure 8 Schematic diagram of the enlarged structure of part B.

[0037] Fig.10 This is a schematic diagram of the installation of a partial structure of the intermittent position adjustment linkage part provided by the present invention from a top view.

[0038] The above drawings include the following reference numerals:

[0039] 1. Inspection table; 2. Bearing shaft; 3. Ring-shaped disk; 4. Self-clamping mechanism; 41. Rectangular installation slot; 42. U-shaped rectangular frame; 43. Transparent plate; 44. Rotating shaft; 45. L-shaped clamping plate; 46. Support claw; 47. Trigger assembly; 471. Strip groove; 472. Sliding column; 473. Push frame; 474. Sliding groove; 475. Oblique pressure plate; 48. Clamping assembly; 481. Gear; 482. Strip slide plate; 483. Rack; 484. Strip frame; 485. Counterweight; 48 6. Shift column; 5. Double-sided visual inspection mechanism; 51. L-shaped plate; 52. Two-way reciprocating electric telescopic rod; 53. Mounting frame; 54. Visual inspection head; 55. Annular fill light; 6. Intermittent positioning linkage unit; 61. Annular reel; 62. Reset torsion spring; 63. Slot; 64. Elastic shift piece; 65. Pull cable; 66. Push rod; 67. Cable guide wheel; 7. Alignment matching unit; 71. Y-shaped alignment frame group; 72. Alignment rod; 8. Annular groove; 9. Hemispherical groove; 10. Spring telescopic column. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0041] See also Figure 1 and Figure 2 The present invention provides a technical solution: a SMT surface mount reflow soldering process, and the specific SMT surface mount reflow soldering process steps are as follows:

[0042] S1. Solder paste printing: Print a thin layer of solder paste on the pads of the PCB circuit board.

[0043] S2. SMT operation: Use a precision SMT machine to place SMT components on the pre-printed solder paste position on the PCB circuit board for SMT operation.

[0044] S3, reflow soldering operation: put the PCB circuit board with SMT components into the reflow soldering furnace for reflow soldering operation.

[0045] S4, cooling and curing: Cool and cure the PCB after reflow soldering to make the SMT components completely fixed on the PCB.

[0046] S5, quality inspection: the PCB circuit boards after cooling and curing are sequentially placed into the self-clamping mechanism 4 for limiting, and then the double-sided visual inspection mechanism 5 is used for quality inspection.

[0047] The SMT surface mount reflow soldering process steps in the above steps S1-S5 need to be completed by the detection table 1, the bearing shaft 2, the annular disk 3, the self-clamping mechanism 4, the double-sided visual detection mechanism 5, the intermittent positioning linkage part 6 and the alignment matching part 7.

[0048] A load-bearing shaft 2 is rotatably connected to the middle of the upper end surface of the detection table 1, and an annular disk 3 is fixedly connected to the outside of the load-bearing shaft 2. Several self-clamping mechanisms 4 for quickly limiting the PCB circuit board are equidistantly arranged on the annular disk 3 in the circumferential direction. A double-sided visual inspection mechanism 5 for simultaneous visual inspection of both sides of the PCB circuit board is arranged on the upper end surface of the detection table 1. An intermittent positioning linkage part 6 for interlocking to intermittently rotate the annular disk 3 to adjust the position of the self-clamping mechanism 4 is installed between the double-sided visual inspection mechanism 5 and the load-bearing shaft 2. A positioning matching part 7 for maintaining the stability of the inspection position is installed between the double-sided visual inspection mechanism 5 and the annular disk 3.

[0049] See also Figure 4 , Figure 5 and Figure 6 In this embodiment, the self-clamping mechanism 4 includes a rectangular mounting groove 41 provided on the annular disk 3, a U-shaped rectangular frame 42 is fixedly connected to the rectangular mounting groove 41 through a fixing rod, a transparent plate 43 is embedded and fixedly connected to the U-shaped rectangular frame 42, a rotating shaft 44 is rotatably connected to the vertical section of the U-shaped rectangular frame 42, a torsion spring is fixedly connected between the rotating shaft 44 and the U-shaped rectangular frame 42, an L-shaped clamping plate 45 is fixedly connected to the outside of the rotating shaft 44, and a supporting claw 46 is fixedly connected to the lower part of the L-shaped clamping plate 45 at equal intervals, a plurality of strip-shaped grooves corresponding to the supporting claw 46 are equidistantly provided on the U-shaped rectangular frame 42, two triggering components 47 corresponding to the L-shaped clamping plate 45 and used to drive the L-shaped clamping plate 45 to rotate and clamp the PCB circuit board are symmetrically arranged on the transverse section of the U-shaped rectangular frame 42, and a tightening component 48 for further clamping the L-shaped clamping plate 45 to the PCB circuit board is installed between the two rotating shafts 44 and the rectangular mounting groove 41.

[0050] See also Figure 4 and Figure 7 The trigger assembly 47 includes two strip grooves 471 symmetrically opened on the side end surface of the transverse section of the U-shaped rectangular mounting frame, a sliding column 472 is slidably connected in the strip groove 471, and a push frame 473 for cooperating with the support claw 46 is fixedly connected between the two sliding columns 472. A sliding groove 474 corresponding to and connected to the strip groove 471 is symmetrically opened on the upper end surface of the transverse section of the U-shaped rectangular frame 42, and an inclined pressure plate 475 that abuts against the outside of the sliding column 472 is hinged in the sliding groove 474.

[0051] See also Figure 4 , Figure 6 and Figure 7 The tightening assembly 48 includes a gear 481 fixedly connected to the same side end of the rotating shaft 44, a strip slide 482 is slidably connected to the side groove wall of the rectangular mounting groove 41 through a sliding sleeve, and the side end surface of the strip slide 482 is rotationally symmetrically fixedly connected with two racks 483 respectively meshing with the gear 481, a strip frame 484 is hingedly connected to the side groove wall of the rectangular mounting groove 41 close to the strip slide 482, a counterweight block 485 is fixedly connected to the upper end surface of the strip frame 484, and a shifting post 486 slidably connected in the strip frame 484 is fixedly connected to the side of the strip slide 482 close to the strip frame 484.

[0052] First, the PCB circuit board is placed in the U-shaped rectangular frame 42, and then, under the weight of the PCB circuit board, the inclined pressure plate 475 is pressed to rotate around the hinge point and gradually into the slide groove 474. During the rotation of the inclined pressure plate 475, the sliding column 472 is gradually squeezed, so that the sliding column 472 gradually moves toward the vertical section of the U-shaped rectangular frame 42, and the sliding column 472 then drives the push frame 473 to move synchronously. During the movement of the push frame 473, it touches the support claw 46 and rotates it. The support claw 46 then drives the L-shaped clamping plate 45 to rotate around the rotating shaft 44 until the horizontal section of the L-shaped clamping plate 45 contacts the upper part of the PCB circuit board, so that the PCB circuit board can be automatically clamped by its own weight. The rotation of the L-shaped clamping plate 45 will also drive the rotating shaft 44 to rotate, and the rotating shaft 44 then drives the gear 481 to rotate. The rotation of the gear 481 drives the rack 483 to move in the direction away from the center of the annular disk 3, and then drives the strip slide plate 482 to move The bar frame 484 is tilted from its original vertical position by the bar slide 482, and the bar slide 482 is moved to its original position by the bar slide 482.

[0053] The PCB circuit board can be quickly and automatically clamped and limited by its own weight when placed, which simplifies the additional limiting operation steps, achieves stable fixation of the circuit board, ensures that the position and angle of each circuit board are consistent during the detection process, and improves the consistency and reliability of the detection results.

[0054] See also Figure 2 , Figure 3 and Figure 8 In this embodiment, the double-sided visual inspection mechanism 5 includes an L-shaped plate 51 fixedly connected to the upper end surface of the inspection platform 1, a two-way reciprocating electric telescopic rod 52 is embedded and fixedly connected in the transverse section of the L-shaped plate 51, and a mounting frame 53 is fixedly connected to the end of the two-way reciprocating electric telescopic rod 52. A visual inspection head 54 is provided in the two mounting frames 53, and a ring-shaped fill light 55 is fixedly connected to the side of the mounting frame 53 close to the annular disk 3 through a connecting rod.

[0055] See also Figure 8 , Fig. 9 and Fig.10 The intermittent adjustment linkage part 6 includes an annular reel 61 rotatably connected to the upper end surface of the detection platform 1 and sleeved on the outside of the load-bearing shaft 2. The annular reel 61 and the detection platform 1 are fixedly connected with a reset torsion spring 62. The outer wall of the circumference of the load-bearing shaft 2 is equidistantly provided with a plurality of slots 63. The inner wall of the circumference of the annular reel 61 is fixedly connected with an elastic paddle 64 that cooperates with the slot 63. A cable 65 is wound around the annular reel 61. One end of the cable 65 away from the annular reel 61 is fixedly connected to the upper end surface of the detection platform 1 through a connecting block. A top rod 66 that cooperates with the cable 65 is fixedly connected to the lower end surface of the mounting frame 53 at the bottom. An empty slot is provided on the upper end surface of the detection platform 1 and directly below the top rod 66. A cable guide wheel 67 is rotatably connected to the upper end surface of the detection platform 1 and located at the rear of the empty slot through a support plate.

[0056] See also Fig. 9 An annular groove 8 is provided on the outside of the bearing shaft 2, and a plurality of hemispherical grooves 9 corresponding to the rectangular mounting through grooves 41 are equidistantly provided on the annular groove 8 in the circumferential direction. A spring telescopic column 10 which contacts the annular groove 8 is fixedly connected to the upper end surface of the detection platform 1 through a vertical plate.

[0057] After the PCB circuit board is placed and limited, the double-sided visual inspection mechanism 5 is controlled to operate, and the two-way reciprocating electric telescopic rod 52 is energized to continuously extend and contract, and the two-way reciprocating electric telescopic rod 52 then drives the two mounting frames 53 to move toward each other. When the two mounting frames 53 move closer to each other, they will drive the visual inspection head 54 and the annular fill light 55 to gradually move closer to the annular disk 3. At this time, the annular disk 3 is in a stationary state, so that the upper and lower surfaces of the PCB circuit board can be inspected at the same time. After the inspection is completed, the two-way reciprocating electric telescopic rod 52 drives the mounting frames 53 to move closer to each other. After the two mounting frames 53 move away from each other for a certain distance, the mounting frame 53 at the lower portion drives the push rod 66 to touch the cable 65 and continue to move downward, and the push rod 66 then touches the cable 65 and enters the empty groove, and the cable 65 is pushed and then pulls the annular reel 61 to rotate, and the annular reel 61 then drives the elastic paddle 64 to rotate, and the elastic paddle 64 is inserted into the slot 63 and drives the bearing shaft 2 to rotate synchronously, and the bearing shaft 2 then drives the annular disk 3 to rotate for a certain angle until it drives the next self-clamping mechanism 4 to move to the position of the double-sided visual inspection mechanism 5.

[0058] Then the two-way reciprocating electric telescopic rod 52 begins to repeat the above initial steps again: the two-way reciprocating electric telescopic rod 52 contracts and drives the mounting frame 53 to move closer to each other, and the mounting frame 53 then drives the top rod 66 and the cable 65 to gradually separate, and then the reset torsion spring 62 in the torsion state drives the annular reel 61 to rotate in the opposite direction and reset, and the annular reel 61 rewinds and rewinds the cable 65 in the relaxed state after separation from the top rod 66 during the reverse process, and drives the elastic paddle 64 to rotate synchronously during the reverse process of the annular reel 61, and the elastic paddle 64 in the reverse motion passes over the outside of the slot 63, and is elastically retracted. The spring telescopic column 10 is inserted into the hemispherical groove 9 which changes its position as the load-bearing shaft 2 rotates to adjust the load-bearing shaft 2, which can prevent the annular reel 61 from driving the load-bearing shaft 2 to rotate during the reversal process. Through the linkage design, the double-sided visual inspection mechanism 5 can immediately drive the annular disk 3 to rotate after one circuit board inspection is completed, and move the next circuit board to the inspection position, thereby realizing continuous operation and improving the inspection efficiency. At the same time, it also reduces the number of driving sources used. The linkage design ensures the synchronization during the inspection process, makes the operation of different parts more coordinated, and improves the accuracy and consistency of the inspection.

[0059] See also Figure 3 In this embodiment, the alignment and matching part 7 includes a plurality of groups of Y-shaped alignment frame groups 71 which are equidistantly fixedly connected to the upper end surface of the annular disk 3 and correspond to the rectangular mounting grooves 41. The upper mounting frame 53 is symmetrically fixedly connected with alignment rods 72 which match the Y-shaped alignment frame groups 71 through fixed columns.

[0060] When the two mounting frames 53 are driven toward the annular disk 3 to inspect the PCB circuit board, the mounting frame 53 at the upper part drives the alignment rod 72 to move synchronously through the fixing column, so that the alignment rod 72 gradually moves downward. After the alignment rod 72 moves downward, it will gradually dock with the Y-shaped alignment frame group 71. During the docking process, if the PCB circuit board is not completely located under the visual inspection head 54, the alignment rod 72 will hit the inclined surface of the Y-shaped alignment frame group 71 and squeeze the Y-shaped alignment frame group 71 to move. Then, the annular disk 3 is driven to rotate slightly, so that the PCB circuit board moves to the bottom of the visual inspection head 54. At this time, the alignment rod 72 moves to the vertical section of the Y-shaped alignment frame group 71. Through the combination of the alignment rod 72 and the Y-shaped alignment frame group 71, the position of the PCB circuit board can be automatically adjusted and limited during the inspection process, thereby ensuring the stability of the position of the PCB circuit board during inspection. Limiting the inspection position can ensure the precise positioning of the circuit board for each inspection, reduce the inspection error, reduce the false alarm rate, and improve the accuracy and stability of the inspection.

[0061] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0062] In addition, the terms "first", "second", "number one", "number two" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", "number one", "number two" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0063] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0064] The embodiments of this specific implementation method are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, all equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A SMT surface mount reflow process, characterized by: The specific SMT surface mount reflow steps are as follows: S1. Solder paste printing: Print a thin layer of solder paste on the pads of the PCB circuit board; S2, patch operation: Use a precision placement machine to place SMT components on the pre-printed solder paste position on the PCB circuit board for patch operation; S3, reflow soldering operation: put the PCB circuit board with SMT components into the reflow soldering furnace for reflow soldering operation; S4, cooling and curing: Cooling and curing the PCB after reflow soldering to ensure that the SMT components are completely fixed on the PCB. S5, quality inspection: the PCB circuit boards after cooling and solidification are sequentially placed into the self-clamping mechanism (4) for positioning, and then the quality is inspected by the double-sided visual inspection mechanism (5); The SMT surface mount reflow soldering process steps in the above steps S1-S5 need to be completed by the detection table (1), the bearing shaft (2), the ring disk (3), the self-clamping mechanism (4), the double-sided visual detection mechanism (5), the intermittent positioning linkage part (6) and the alignment matching part (7); wherein: The middle part of the upper end face of the detection platform (1) is rotatably connected to a bearing shaft (2), the outer part of the bearing shaft (2) is fixedly connected to an annular disk (3), a plurality of self-clamping mechanisms (4) for quickly limiting the position of the PCB circuit board are equidistantly arranged on the annular disk (3), the upper end face of the detection platform (1) is provided with a double-sided visual inspection mechanism (5) for visually inspecting both sides of the PCB circuit board at the same time, an intermittent position adjustment linkage part (6) for interlocking to intermittently rotate the annular disk (3) to adjust the position of the self-clamping mechanism (4) is installed between the double-sided visual inspection mechanism (5) and the bearing shaft (2), and a positioning matching part (7) for maintaining the stability of the inspection position is installed between the double-sided visual inspection mechanism (5) and the annular disk (3); The double-sided visual inspection mechanism (5) comprises an L-shaped plate (51) fixedly connected to the upper end surface of the inspection platform (1); a bidirectional reciprocating electric telescopic rod (52) is embedded and fixedly connected in the transverse section of the L-shaped plate (51); the ends of the bidirectional reciprocating electric telescopic rod (52) are fixedly connected to mounting frames (53); a visual inspection head (54) is provided in each of the two mounting frames (53); and a ring-shaped fill light (55) is fixedly connected to the side of the mounting frame (53) close to the annular disk (3) via a connecting rod; The alignment matching portion (7) comprises a plurality of Y-shaped alignment frame groups (71) fixedly connected to the upper end surface of the annular disk (3) at equal intervals in the circumferential direction and corresponding to the rectangular mounting slots (41); and alignment rods (72) that match the Y-shaped alignment frame groups (71) are fixedly connected to the upper mounting frame (53) in a symmetrical manner via fixed columns. The intermittent position adjustment linkage part (6) comprises an annular reel (61) rotatably connected to the upper end surface of the detection platform (1) and sleeved on the outside of the bearing shaft (2); the annular reel (61) and the detection platform (1) are fixedly connected to a reset torsion spring (62); a plurality of slots (63) are equidistantly provided on the circumferential outer wall of the bearing shaft (2); an elastic paddle (64) that cooperates with the slots (63) is fixedly connected to the circumferential inner wall of the annular reel (61); and the annular reel (61) is fixedly connected to the inner wall of the annular reel. 1) A cable (65) is wound around the test platform (1), and one end of the cable (65) away from the annular reel (61) is fixedly connected to the upper end surface of the test platform (1) through a connecting block. The lower end surface of the mounting frame (53) located at the lower part is fixedly connected to a push rod (66) that cooperates with the cable (65). An empty slot is provided on the upper end surface of the test platform (1) and located directly below the push rod (66). The upper end surface of the test platform (1) and located at the rear of the empty slot is rotatably connected to a guide rope wheel (67) through a support plate.

2. The SMT surface mount reflow soldering process according to claim 1, wherein: The self-clamping mechanism (4) comprises a rectangular mounting groove (41) provided on the annular disk (3), a U-shaped rectangular frame (42) being fixedly connected to the rectangular mounting groove (41) via a fixing rod, a transparent plate (43) being fixedly connected to the U-shaped rectangular frame (42), a rotating shaft (44) being rotatably connected to the vertical section of the U-shaped rectangular frame (42), a torsion spring being fixedly connected between the rotating shaft (44) and the U-shaped rectangular frame (42), an L-shaped clamping plate (45) being fixedly connected to the outside of the rotating shaft (44), and the L-shaped clamping plate (43) being fixedly connected to the outside of the rotating shaft (44). 5) The lower portion is fixedly connected with supporting claws (46) at equal intervals, and the U-shaped rectangular frame (42) is provided with a plurality of strip-shaped through slots corresponding to the supporting claws (46) at equal intervals. Two triggering components (47) corresponding to the L-shaped clamping plate (45) and used to drive the L-shaped clamping plate (45) to rotate and clamp the PCB are symmetrically arranged on the transverse section of the U-shaped rectangular frame (42). A tightening component (48) for further clamping the L-shaped clamping plate (45) to the PCB is installed between the two rotating shafts (44) and the rectangular mounting through slot (41).

3. The SMT surface mount reflow soldering process according to claim 2, wherein: The touch assembly (47) includes two strip grooves (471) symmetrically opened on the side end surface of the transverse section of the U-shaped rectangular installation frame, a sliding column (472) is slidably connected in the strip groove (471), and a push frame (473) for cooperating with the support claw (46) is fixedly connected between the two sliding columns (472). A sliding groove (474) corresponding to and connected to the strip groove (471) is symmetrically opened on the upper end surface of the transverse section of the U-shaped rectangular frame (42), and an inclined pressure plate (475) is hinged in the sliding groove (474) and abuts against the outside of the sliding column (472).

4. The SMT surface mount reflow soldering process according to claim 2, wherein: The tightening assembly (48) includes a gear (481) fixedly connected to the same side end of the rotating shaft (44); the side groove wall of the rectangular installation slot (41) is slidably connected to a strip slide (482) through a sliding sleeve; the side end surface of the strip slide (482) is rotationally symmetrically fixedly connected to two racks (483) respectively meshing with the gear (481); the groove wall of one side of the rectangular installation slot (41) close to the strip slide (482) is hingedly connected to a strip frame (484); the upper end surface of the strip frame (484) is fixedly connected to a counterweight (485); and the side of the strip slide (482) close to the strip frame (484) is fixedly connected to a shifting post (486) slidably connected to the strip frame (484).

5. The SMT surface mount reflow soldering process according to claim 2, wherein: An annular groove (8) is provided on the outside of the bearing shaft (2), and a plurality of hemispherical grooves (9) corresponding to the rectangular mounting grooves (41) are provided on the annular groove (8) at equal intervals in the circumferential direction. The upper end surface of the detection platform (1) is fixedly connected to a spring telescopic column (10) that contacts the annular groove (8) via a vertical plate.

Images