A fully automated selective welding system and method

Abstract

This invention provides a fully automated selective soldering system and method, comprising: a flux spraying mechanism arranged sequentially; a first conveying mechanism for conveying a PCB board to the spraying station of the flux spraying mechanism; a preheating mechanism for preheating the sprayed PCB board, wherein the preheating mechanism includes a third conveying mechanism; a second conveying mechanism for conveying the preheated PCB board above a rotary soldering mechanism; and a rotary soldering mechanism for soldering the preheated PCB board. The flux spraying mechanism is located below the first conveying mechanism, and the rotary soldering mechanism is located below the second conveying mechanism. The first and second conveying mechanisms are respectively connected to both ends of the third conveying mechanism. This arrangement simplifies the structure of the transmission section, making the overall equipment structure more compact; and significantly shortens the path of the PCB board between different processes, resulting in a substantial improvement in work efficiency.

Description

Technical Field

[0001] This invention relates to the field of welding equipment technology, and in particular to a fully automatic selective welding system and method. Background Technology

[0002] In automated production, soldering is an indispensable part of many electronic products and equipment, and wave soldering technology is widely used in circuit board assembly, such as integrated circuits, printed circuit boards, electronic components, automotive parts, etc.

[0003] Chinese invention application CN202210295535.0 discloses a wave soldering device, comprising: a body having a connected inlet and outlet, and a transfer track installed on the body, the transfer track being adapted to feed the product to be soldered from the inlet to the outlet; a flux spraying device, a preheating device, and a welding device are distributed within the body along the feeding direction of the transfer track, the transfer track including a first track and a second track that are independent of each other, the first track being arranged opposite to the flux spraying device. However, the preheating track in the above solution is long and far, not only occupying expensive factory space but also increasing the cost of future track maintenance.

[0004] Chinese invention patent CN201611006043.6 discloses a desktop selective wave soldering machine. A movable mounting frame is installed on the upper side of a fixed mounting base, and a movable support plate is mounted on the movable mounting frame. A solder pump assembly is installed on the lower side of the movable support plate on the fixed mounting base. A Y-axis drive linear module is installed on the fixed mounting base, and a Z-axis drive linear module is installed at the drive end of the Y-axis drive linear module. An X-axis drive linear module is installed on the movable mounting frame. The solder pump assembly includes a solder pump mounting frame, a solder pot assembly, and a solder liquid pumping mechanism. The solder pot assembly includes a solder pot body, a solder pot cover, and an electric heating plate. The solder liquid pumping mechanism includes a housing base, a housing panel, a drive impeller, a drive shaft, a pumping drive motor, and a solder liquid nozzle. This desktop selective wave soldering machine is equipped with a controller. However, due to the single solder pump assembly, it is difficult to meet the multi-process soldering requirements of single boards with different solder joint processes for the same product.

[0005] Existing wave soldering processes generally include flux spraying, preheating, and soldering. However, existing equipment has the following drawbacks: the transfer process of the circuit board to be soldered between each stage is lengthy, which affects the overall soldering time and results in low soldering efficiency; secondly, the excessively long and illogical transport mechanisms between stages not only occupy expensive factory space but also increase future maintenance costs; furthermore, the excessively long transport mechanisms result in the PCB board entering the soldering station at a low temperature after preheating, failing to meet soldering requirements and further affecting soldering quality. Additionally, existing selective wave soldering machines can only provide one soldering process per operation, failing to simultaneously meet the needs of different soldering processes for the same product, and suffer from large size and poor integration.

[0006] Therefore, it is necessary to design a fully automated selective welding system to solve the above problems. Summary of the Invention

[0007] The purpose of this invention is to provide a fully automatic selective welding system that is compact in structure, has high welding efficiency, and provides stable welding quality.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a fully automatic selective welding system, comprising sequentially arranged...

[0009] A flux spraying mechanism is used to spray flux onto the areas of a PCB board that are to be soldered.

[0010] The first conveying mechanism is used to convey the PCB board to the spraying station of the flux spraying mechanism;

[0011] A preheating mechanism is used to preheat the sprayed PCB board. The preheating mechanism is a storage-type preheating mechanism with at least two layers. The preheating mechanism is equipped with a third conveying mechanism and a Z-axis module.

[0012] The second conveying mechanism is used to convey the preheated PCB board to the top of the rotary welding mechanism;

[0013] A rotary welding mechanism is used to weld preheated PCB boards.

[0014] The flux spraying mechanism is located below the first conveying mechanism, the rotary welding mechanism is located below the second conveying mechanism, and the first and second conveying mechanisms are respectively connected to both ends of the third conveying mechanism.

[0015] As a further improvement of the present invention, the preheating mechanism includes at least two stacked preheating units, each of which is provided with the third conveying mechanism. The Z-axis module is used to adjust the position of the preheating unit in the Z-axis direction so as to connect the first conveying mechanism with the third conveying mechanism.

[0016] As a further improvement of the present invention, the preheating unit includes an upper preheater and a lower preheater, and a preheating cavity is formed between the upper preheater and the lower preheater.

[0017] As a further improvement of the present invention, the upper preheater includes a metal shell and a hot air unit inside it, and the lower preheater is a far-infrared lamp.

[0018] As a further improvement to the present invention, each of the preheating units also includes a temperature controller.

[0019] As a further improved technical solution of the present invention, the first conveying mechanism includes a bracket, two first conveying tracks arranged side by side, a first roller group or a first chain disposed on the first conveying track, and a first conveying motor for driving the first roller group or the first chain. The PCB board moves under the drive of the two first roller groups or the first chain.

[0020] As a further improvement of the present invention, the first conveying mechanism further includes a width adjustment component, which includes a width adjustment screw, a width adjustment screw nut, and a width adjustment motor. The width adjustment screw and the width adjustment screw nut drive one of the first conveying tracks to move closer to or further away from the other first conveying track.

[0021] As a further improvement of the present invention, the first conveying mechanism further includes a height adjustment component, which includes a height adjustment screw, a height adjustment screw nut, and a height adjustment motor. The height adjustment screw nut is fixedly connected to the bracket to adjust the height of the first conveying track and the first roller group or the first chain.

[0022] As a further improvement of the present invention, the first conveying mechanism further includes positioning components respectively disposed on two first conveying tracks. Each positioning component includes a positioning cylinder, an output rod, a support base and a positioning plate connected in sequence. The positioning cylinder drives the positioning plate to move in a direction perpendicular to the PCB board. The positioning plate cooperates with the first roller group or the first chain to clamp the PCB board to fix it.

[0023] As a further improvement of the present invention, the rotary welding mechanism includes a base and a welding assembly, wherein the welding assembly includes two welding furnaces movably mounted on a main fixed plate.

[0024] As a further improvement of the present invention, the rotary welding mechanism further includes a rotary component disposed on the base for driving the welding component to rotate and a lifting component for driving the welding component to rise and fall.

[0025] As a further improvement of the present invention, the rotary welding mechanism further includes an adjustment component, which includes a cam that can adjust the height difference between the two welding furnaces.

[0026] As a further improvement of the present invention, the adjustment component is adapted to prevent the two welding furnaces from colliding with the PCB board during rotation.

[0027] As a further improvement of the present invention, the cam is located in the circumferential direction of the welding furnace, and the bottom of the welding furnace is provided with a fisheye bearing. When one of the welding furnaces rotates to above the cam, the fisheye bearing cooperates with the cam to lift the welding furnace.

[0028] As a further improved technical solution of the present invention, the welding furnace includes a furnace body, a nozzle, an upper fixing plate for fixing the furnace body, a lower fixing plate, and a plurality of fixing rods connecting the upper fixing plate and the lower fixing plate. The upper fixing plate is located in the circumferential direction of the furnace body. The fixing rods pass through the main fixing plate, and the welding furnace can move up and down relative to the main fixing plate. The main fixing plate is provided with a linear bearing, and the lower surface of the upper fixing plate is provided with a shaft fixing seat for mounting the fixing rods.

[0029] As a further improvement of the present invention, the rotating component includes a fixed gear fixed on the base, a rotating bearing, a rotating shaft, a rotating motor fixed to the rotating shaft, and a movable gear driven by the rotating motor. The movable gear meshes with the fixed gear to drive the rotating shaft and the welding component to rotate.

[0030] As a further improvement of the present invention, the lifting assembly includes a rotating platform fixed to the rotating shaft, a lifting motor, a lead screw, and a scissor arm disposed on the rotating platform. The scissor arm is disposed between the main fixed plate and the rotating platform, and the lifting motor drives the main fixed plate to lift and lower through the lead screw and the scissor arm.

[0031] As a further improved technical solution of the present invention, the rotary welding mechanism also includes a vision component, which is used to perform optical acquisition and inspection of the PCB board, and is disposed on the upper surface of the main fixing plate and located between the welding furnaces.

[0032] As a further improvement of the present invention, the rotary welding mechanism further includes a laser heat compensation component, which is disposed above the main fixing plate and close to the nozzle to heat and compensate the PCB board.

[0033] As a further improvement of the present invention, a moving mechanism is also included, which is located below the rotary welding mechanism and is used to drive the rotary welding mechanism to move in the horizontal direction.

[0034] As a further improvement of the present invention, it also includes an AOI inspection module, which can directly check the yield of the solder joints after soldering is completed, and determine whether the PCB board needs to be re-soldered or an alarm is triggered after it is moved out of the workstation based on the results.

[0035] To achieve the above objectives, the present invention adopts the following technical solution: a fully automatic selective soldering method, which uses the above-mentioned fully automatic selective soldering system to operate on a PCB board, the steps of which include:

[0036] S1: PCB board feeding and transfer: The PCB board is transported to the flux spraying station of the first conveying mechanism;

[0037] S2: Precise spraying of the PCB board is performed using a vision module and an electronic spray gun;

[0038] S3: By controlling the third conveying mechanism to dock with the first conveying mechanism through the Z-axis module, the sprayed PCB board can be placed into different layers of the preheating mechanism for preheating.

[0039] S4: By connecting the third conveying mechanism with the second conveying mechanism, the preheated PCB board can be conveyed to the top of the rotary welding mechanism;

[0040] S5: The preheated PCB board is welded using the rotary welding mechanism.

[0041] As can be seen from the above technical solutions, the fully automatic selective welding system of the present invention places the flux spraying mechanism below the first conveying mechanism, the rotary welding mechanism below the second conveying mechanism, and connects the first and second conveying mechanisms to the two ends of the third conveying mechanism respectively, so that the conveying path of the PCB board is a straight line, and the spraying, preheating and welding processes are completed on the transport path formed by the first, third and second conveying mechanisms. This greatly simplifies the structure of the transmission part, makes the overall structure of the equipment more compact, and greatly shortens the transmission path of the PCB board between various processes, thus greatly improving the work efficiency.

[0042] On the other hand, the design of the storage-type preheating mechanism greatly reduces the equipment's footprint, and provides better control over the temperature zone and future maintenance.

[0043] On the other hand, the rotary welding mechanism, by setting up two rotatable welding furnaces, can perform different processes on different positions of the same PCB board. It can be specifically set up to adapt to different solder joint sizes, while meeting the needs of different welding processes. It also has a compact structure and high welding efficiency.

[0044] On the other hand, by setting up adjustment components, a height difference is created between the two welding furnaces during rotation and welding positions, preventing the welding furnaces from colliding with the PCB board during rotation and causing damage to the product. Attached Figure Description

[0045] Figures 1(a) and (b) are schematic diagrams of a fully automatic selective welding system according to an embodiment of the present invention.

[0046] Figure 2 Figure 1 shows a perspective view of the flux spraying mechanism, the first conveying mechanism, and the preheating mechanism.

[0047] Figure 3 for Figure 2 A three-dimensional view of the flux spraying mechanism.

[0048] Figure 4 for Figure 2 A three-dimensional view of the first conveying mechanism.

[0049] Figure 5 for Figure 2 A three-dimensional view of the first conveyor mechanism from another angle.

[0050] Figure 6 for Figure 5 A magnified view of the positioning component.

[0051] Figure 7 for Figure 2 A three-dimensional view of the preheating unit and the third conveying mechanism.

[0052] Figure 8 This is a perspective view of the rotary welding mechanism, the second conveying mechanism, and the moving mechanism in Figure 1.

[0053] Figure 9 for Figure 8 A three-dimensional view of the rotary welding mechanism.

[0054] Figure 10 for Figure 9 Front view of the rotary welding mechanism.

[0055] Figure 11 for Figure 9 Side view of the rotary welding mechanism. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0057] Please refer to Figure 1. This invention provides a fully automatic selective welding system, which includes a housing, a flux spraying mechanism 1, a first conveying mechanism 2, a preheating mechanism 3, a rotary welding mechanism 10, a second conveying mechanism 20, a moving mechanism 30, and a control unit, all housed within the housing. The housing has a PCB board inlet a and a PCB board outlet b on both sides. The first conveying mechanism 2 connects to the PCB board inlet a for loading the PCB board to be processed; the second conveying mechanism 20 connects to the PCB board outlet b for unloading the welded PCB board.

[0058] The flux spraying mechanism 1, the first conveying mechanism 2, and the preheating mechanism 3 constitute a PCB board pre-treatment device for flux spraying and preheating the PCB board. Please refer to... Figure 2 As shown, the flux spraying mechanism 1 is located below the first conveying mechanism 2 and is used to spray flux onto the parts of the PCB board to be soldered.

[0059] Please participate together Figure 3 As shown, the flux spraying mechanism 1 specifically includes an XY-axis module 101, a vision component 102 mounted on the XY-axis module 101, and a spray gun 103. The XY-axis module 101 drives the vision component 102 and the spray gun 103 to move in the X-axis and Y-axis directions. The vision component 102 and the spray gun 103 are positioned close to each other. The flux spraying mechanism 1 is signal-connected to the control unit. The control unit's vision module calculates data based on the PCB board image information obtained by the vision component, and then controls the XY-axis module 101 to move the spray gun 103 to the designated position for precise spraying. The flux is precisely sprayed onto the areas on the bottom surface of the PCB that need to be soldered, rather than the entire PCB board, thereby avoiding contamination of areas outside the solder joints and achieving simple and precise spraying.

[0060] The first conveying mechanism 2 is used to load the PCB board to be processed and convey it to the spraying station of the flux spraying mechanism 1. Please refer to... Figure 4 As shown, the first conveying mechanism 2 includes a support 21, two first conveying tracks 22 arranged side by side, a first roller group 23 disposed on the first conveying track 22, and a first conveying motor 24 driving the first roller group 23. The PCB board 100 moves under the drive of the two first roller groups 23. In other embodiments, the first roller group 23 can be replaced by chain drive.

[0061] The first conveying mechanism 2 further includes a width adjustment component 25 for adjusting the width between the two first conveying tracks 22. The width adjustment component 25 includes a width adjustment screw 251, a width adjustment screw nut 252, and a width adjustment motor 253. The width adjustment screw 251 and the width adjustment screw nut 252 drive one of the first conveying tracks 22 to move closer to or further away from the other first conveying track 22. Preferably, the width adjustment component 25 includes two sets of parallel width adjustment screws 251 and width adjustment screw nuts 252, and the width adjustment motor 253 drives the two width adjustment screws 251 to move simultaneously through gear transmission.

[0062] Please refer to Figure 2 and Figure 5 As shown, the first conveying mechanism 2 also includes a height adjustment component 26, which includes a height adjustment screw, a height adjustment screw nut, and a height adjustment motor. The height adjustment screw nut is fixedly connected to the bracket to adjust the height of the first conveying track 22 and the first roller group 23.

[0063] Please refer to Figure 5 and Figure 6 As shown, the first conveying mechanism 2 also includes positioning components 27 respectively disposed on two first conveying tracks 22. Each positioning component 27 includes a positioning cylinder 271, an output rod 272, a support base 273, and a positioning plate 274 connected in sequence. The positioning cylinder drives the positioning plate 274 to move in a direction perpendicular to the PCB board. The positioning plate 274 cooperates with the first roller group 23 to clamp and fix the PCB board. In addition, sensors are provided at the front end, middle, and rear end of the first conveying mechanism 2. The sensors are signal-connected to the control unit to identify the position of the PCB board 100 entering the first conveying track 22, and control the first conveying motor 24 and the positioning components 27 to operate according to the position information of the PCB board 100.

[0064] Preheating mechanism 3 is used to preheat the coated PCB board. Please refer to... Figure 2 and Figure 7 As shown, the preheating mechanism 3 is located on one side of the first conveying mechanism 2, and includes a plurality of stacked preheating units 31, a third conveying mechanism 32 disposed in each preheating unit 31, and a Z-axis module 33. Preferably, in this embodiment, the number of preheating units 31 is three. Each preheating unit 31 is provided with a separate third conveying mechanism 32.

[0065] The preheating unit 31 specifically includes a shell 311 with openings at both ends, an upper preheater and a lower preheater disposed within the shell 311, forming a preheating cavity 312 between the upper and lower preheaters. This top-and-bottom heating structure further accelerates the preheating speed and improves preheating efficiency. Preferably, the upper preheater includes a metal shell and a hot air unit inside, and the lower preheater is a far-infrared lamp. Each preheating unit is also equipped with an individual temperature controller to precisely control the preheating temperature required for the product.

[0066] The third conveying mechanism 32 includes two second conveying tracks 321 arranged side by side, a second roller group 322 disposed on the second conveying track 321, and a second conveying motor 323 that drives the second roller group 322.

[0067] The Z-axis module 33 is used to adjust the position of the preheating unit in the Z-axis direction to connect the third conveying mechanism 32 with the first conveying mechanism 22. Specifically, all preheating units 31 are fixed on the Z-axis module 33. The Z-axis module 33 drives the preheating units 31 to move up and down, so that each third conveying mechanism 32 connects with the first conveying mechanism 22 when needed to transfer the coated PCB board to the preheating unit 31. The cooperation of the Z-axis module 33 and the multi-layer preheating units 31 greatly reduces the equipment's footprint and provides better control over the temperature zone and equipment maintenance. On the other hand, the multi-layer preheating units 31 can be used simultaneously, which greatly improves the efficiency of the pre-soldering treatment of the PCB board 100.

[0068] The rotary welding mechanism 10 is used to weld the points on the PCB board that need to be welded. Please refer to... Figure 8 As shown, the second conveying mechanism 20 is located above the rotary welding mechanism 10 and is used to convey the preheated PCB board from the preheating mechanism 3 to the rotary welding mechanism 10. The moving mechanism 30 is located below the rotary welding mechanism 10 to drive the rotary welding mechanism 10 to move. The moving mechanism 30 includes an X-axis module 301 and a Y-axis module 302.

[0069] Please refer to Figure 9 and Figure 10 As shown, the rotary welding mechanism 10 includes a base 11, a welding assembly 12, a rotating assembly 13, a lifting assembly 14, and an adjusting assembly 15. The welding assembly 12 includes a main fixing plate 121 and two welding furnaces 121 movably mounted on the main fixing plate 120. The welding furnaces 121 spray solder peaks to perform welding from the bottom of the PCB board.

[0070] The use of two sets of intelligent electromagnetic induction pump solder pots enables multi-process soldering of single boards. Solder pot temperature, nitrogen temperature, wave height, and wave correction can all be set by computer. The inner liner of the solder pot is made of titanium alloy and is leak-proof. In other embodiments, it can be interchanged with existing solder pots on existing machines; all wiring uses quick-connect sockets, eliminating the need for manual wiring.

[0071] Specifically, the welding furnace 121 includes a furnace body 122, a nozzle 123, an upper fixing plate 124 and a lower fixing plate 125 for fixing the furnace body 122, and a plurality of fixing rods 126 connecting the upper fixing plate 124 and the lower fixing plate 125. The upper fixing plate 124 is located circumferentially on the furnace body 121. The fixing rods 126 pass through a main fixing plate 120, allowing the welding furnace 121 to move up and down relative to the main fixing plate 120. A linear bearing 127 is provided on the main fixing plate 120, and a shaft fixing seat 128 for mounting the fixing rods 126 is provided on the lower surface of the upper fixing plate 124. The nozzle 123 is a fine-hole nozzle, a long nozzle, or an irregularly shaped nozzle. In this embodiment, the furnace body 122 is an intelligent electromagnetic induction pump soldering furnace, and the furnace body 122 includes a titanium inner liner and an external heating plate.

[0072] Please refer to Figure 9 and Figure 11 As shown, the rotating assembly 13 is mounted on the base 11 and is used to drive the welding assembly 12 to rotate. The rotating assembly 13 includes a fixed gear 131 fixed on the base 11, a rotary bearing, a rotating shaft, a rotary motor 134 fixed to the rotating shaft, and a movable gear 135 driven by the rotary motor 134. The movable gear 135 meshes with the fixed gear 131 to drive the rotating shaft and the welding assembly 12 to rotate. By setting the rotating assembly 13 to drive the two welding furnaces 121 to rotate and reposition, welding can be performed on different positions of the same PCB board. Welding furnaces adapted to different solder joint sizes can be set up to meet different welding process requirements, and the structure is compact with high welding efficiency.

[0073] The lifting assembly 14 is used to lift and lower the welding assembly 12. Please refer to... Figure 9 , Figure 10 and Figure 11 As shown, the lifting assembly 14 includes a rotating platform 141 fixed to the rotating shaft, a lifting motor 142, a lead screw 143, and a scissor arm 144 mounted on the rotating platform 141. The scissor arm 144 is located between the main fixed plate 120 and the rotating platform 141. The lifting motor 142 drives the main fixed plate 120 to rise and fall through the lead screw 143 and the scissor arm 144, thereby driving the two welding furnaces 121 to rise and fall.

[0074] Adjustment component 15 is used to create a height difference between the two welding furnaces 121. Please refer to... Figure 10As shown, the adjustment assembly 15 includes a cam 151 mounted on the base 11 and a fisheye bearing 152 mounted at the bottom of the soldering furnace 121. The cam 151 is located in the circumferential direction of the soldering furnace 121. When one of the soldering furnaces 121 rotates above the cam 151, the fisheye bearing 152 cooperates with the cam 151 to lift the soldering furnace 121. By setting the adjustment assembly, a height difference is created between the two soldering furnaces during rotation and soldering, preventing the two soldering furnaces 121 from colliding with the PCB board during rotation and causing damage to the product.

[0075] Please refer to Figure 9 As shown, the rotary welding mechanism 10 also includes a vision component 16 and a laser temperature compensation component (not shown). The vision component 16 is used for optical acquisition and inspection of the PCB board 100 being welded. The vision component 16 is located on the upper surface of the main fixing plate 120 and between the welding furnaces 121. It also includes an AOI inspection module (not shown), which can directly check the yield of the solder joints after soldering is completed. Based on the results, it determines whether the PCB board needs to be re-welded or whether an alarm should be triggered after it is removed from the welding station.

[0076] The laser temperature compensation component is positioned above the main fixing plate 120 and close to the nozzle 123 to heat and compensate for the temperature of the PCB board. The temperature compensation function depends on the product manufacturing process. The PCB far from the preheating zone will experience a drop in temperature, affecting the product's soldering yield, thus requiring temperature compensation to improve the soldering yield.

[0077] The structure of the second conveying mechanism 20 is the same as that of the first conveying mechanism 2, and will not be described in detail here. After the PCB board is transported online to the designated position by the second conveying mechanism 20, the position of the PCB board to be soldered is first calculated by the vision component 16. The control system then calculates the accurate value and drives the moving mechanism 30 to accurately move the rotating soldering mechanism 10 to the designated position and perform precise soldering.

[0078] The first conveying mechanism 2 and the second conveying mechanism 20 are located on both sides of the preheating mechanism 3. During operation, the first conveying mechanism 2, the third conveying mechanism 32, and the second conveying mechanism 20 are connected in sequence to form a straight module, which transports the PCB board to the spraying station, the preheating station, and the welding station in sequence. The first conveying mechanism 2, the third conveying mechanism 32, and the second conveying mechanism 20 not only play a conveying role, but also carry the PCB board in the above three stations. There is no need to set up separate carrying mechanisms for each section. On the one hand, it greatly simplifies the structure of the transmission part and makes the overall structure of the equipment more compact. On the other hand, it greatly shortens the transmission path of the PCB board between the various processes, which greatly improves the work efficiency.

[0079] The terms used herein, such as “upper,” “lower,” “front,” and “back,” indicating relative spatial positions, are for illustrative purposes to describe the relationship of one feature relative to another, as shown in the accompanying drawings. It is understood that, depending on the product's placement, these terms may be intended to include different orientations besides those shown in the figures, and should not be construed as limiting the claims.

[0080] Furthermore, the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. The understanding of this specification should be based on those skilled in the art. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to the present invention. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A fully automatic selective welding system, characterized in that: Including sequentially set A flux spraying mechanism is used to spray flux onto the areas of a PCB board that are to be soldered. The first conveying mechanism is used to convey the PCB board to the spraying station of the flux spraying mechanism; A preheating mechanism is used to preheat the sprayed PCB board. The preheating mechanism is a storage-type preheating mechanism with at least two layers. The preheating mechanism is equipped with a third conveying mechanism and a Z-axis module. The second conveying mechanism is used to convey the preheated PCB board to the top of the rotary welding mechanism; A rotary welding mechanism is used to weld preheated PCB boards. The flux spraying mechanism is located below the first conveying mechanism, the rotary welding mechanism is located below the second conveying mechanism, and the first and second conveying mechanisms are respectively connected to both ends of the third conveying mechanism. The rotary welding mechanism includes a base and a welding assembly, the welding assembly including two welding furnaces movably mounted on a main fixed plate; The rotary welding mechanism also includes a rotary component mounted on the base for driving the solder of the welding component and a lifting component for driving the welding component to rise and fall. The rotary welding mechanism further includes an adjustment component, which includes a cam that can adjust the height difference between the two welding furnaces; The regulating component is adapted to prevent the two soldering furnaces from colliding with the PCB board during the soldering process; The cam is located on the circumferential axis of the welding furnace. The bottom of the welding furnace is provided with a fisheye bearing. When one of the welding furnaces rotates to above the cam, the fisheye bearing cooperates with the cam to lift the welding furnace and then lock itself. The welding furnace includes a furnace body, a nozzle, an upper fixing plate for fixing the furnace body, a lower fixing plate, and a plurality of fixing rods connecting the upper fixing plate and the lower fixing plate. The upper fixing plate is located in the circumferential direction of the furnace body. The fixing rod passes through the main fixing plate, the welding furnace can move up and down relative to the main fixing plate, the main fixing plate is provided with a linear bearing, and the lower surface of the upper fixing plate is provided with a shaft fixing seat for mounting the fixing rod; The rotating assembly includes a fixed gear fixed to the base, a rotary bearing, a rotating shaft, a rotary motor fixed to the rotating shaft, and a movable gear driven by the rotary motor. The movable gear meshes with the fixed gear to drive the rotating shaft and the welding assembly to rotate. The lifting assembly includes a rotating platform fixed to the rotating shaft, a lifting motor, a lead screw, and a scissor arm disposed on the rotating platform. The scissor arm is disposed between the main fixed plate and the rotating platform. The lifting motor drives the main fixed plate to lift and lower through the lead screw and the scissor arm. The rotary welding mechanism also includes a vision component, which is used to perform optical acquisition and inspection of the PCB board. The vision component is located on the upper surface of the main fixing plate and between the welding furnaces. The rotary welding mechanism also includes a laser heat compensation component, which is located above the main fixing plate and close to the nozzle to heat and compensate the PCB board.

2. The fully automatic selective welding system as described in claim 1, characterized in that: The preheating mechanism includes at least two stacked preheating units, each of which is provided with the third conveying mechanism. The Z-axis module is used to adjust the position of the preheating unit in the Z-axis direction to connect the first conveying mechanism with the third conveying mechanism. The preheating unit includes an upper preheater and a lower preheater, and a preheating cavity is formed between the upper preheater and the lower preheater; The upper preheater includes a metal casing and a hot air unit inside, and the lower preheater is a far-infrared lamp; each preheating unit also includes a temperature controller.

3. The fully automated selective welding system as described in claim 1, characterized in that: The first conveying mechanism includes a bracket, two first conveying tracks arranged side by side, a first roller group or a first chain set on the first conveying track, and a first conveying motor that drives the first roller group or the first chain. The PCB board moves under the drive of the two first roller groups or the first chain. The first conveying mechanism further includes a width adjustment component, which includes a width adjustment screw, a width adjustment screw nut, and a width adjustment motor. The width adjustment screw and the width adjustment screw nut drive one of the first conveying tracks to move closer to or further away from the other first conveying track. The first conveying mechanism further includes a height adjustment component, which includes a height adjustment screw, a height adjustment screw nut, and a height adjustment motor. The height adjustment screw nut is fixedly connected to the bracket to adjust the height of the first conveying track and the first roller group or the first chain. The first conveying mechanism further includes positioning components respectively disposed on two first conveying tracks. Each positioning component includes a positioning cylinder, an output rod, a support base and a positioning plate connected in sequence. The positioning cylinder drives the positioning plate to move in a direction perpendicular to the PCB board. The positioning plate cooperates with the first roller group or the first chain to clamp the PCB board to fix it.

4. The fully automated selective welding system as described in claim 1, characterized in that: It also includes a moving mechanism located below the rotary welding mechanism, used to drive the rotary welding mechanism to move in the horizontal direction; It also includes an AOI inspection module, which can directly check the yield of solder joints after soldering is completed, and determine whether the PCB board needs to be re-soldered or should be moved out of the workstation and an alarm should be triggered based on the results.

5. A fully automated selective soldering method, comprising operating a PCB board using a fully automated selective soldering system as described in any one of claims 1 to 4, characterized in that: S1: PCB board feeding and transfer: The PCB board is transported to the flux spraying station of the first conveying mechanism; S2: Precise spraying of the PCB board is performed using a vision module and an electronic spray gun; S3: By controlling the third conveying mechanism to dock with the first conveying mechanism through the Z-axis module, the sprayed PCB board can be placed into different layers of the preheating mechanism for preheating. S4: By connecting the third conveying mechanism with the second conveying mechanism, the preheated PCB board can be conveyed to the top of the rotary welding mechanism; S5: The preheated PCB board is welded using the rotary welding mechanism.

Images