Photovoltaic junction box welding device

Abstract

The utility model discloses a photovoltaic junction box welding device, belongs to the technical field of photovoltaic junction box welding, and solves the technical problems of low manual welding efficiency and poor quality. The device comprises a machine body and a conveying mechanism, a welding mechanism is arranged below the conveying mechanism, a tin feeding mechanism is arranged below the welding mechanism, and the tin feeding mechanism is installed on a movable platform. Horizontal moving mechanisms are arranged on the two sides of the bottom of the moving platform, lifting mechanisms are arranged on the two sides of the moving platform, and the lifting ends of the two lifting mechanisms are connected with the two sides of the welding mechanism correspondingly. A welding spray head of the welding mechanism is provided with two sub spray heads, the tops of the sub spray heads are concave spherical surfaces, the peripheries of the sub spray heads are convex, two nozzles with opposite spraying angles are formed in the concave spherical surfaces, and the beneficial effects that the welding face is increased, sprayed tin splashing and eddy currents are reduced, and welding seams are effectively filled are achieved. The whole device is high in automation degree and good in coordination, pseudo soldering is reduced, and the welding quality and efficiency are effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic component welding, in particular to a photovoltaic junction box welding device. Background Art

[0002] A photovoltaic junction box is a device that connects the solar array of solar panels and the solar charging control unit. Its primary function is to connect and protect the solar photovoltaic panels, ensuring that the electricity generated by the solar cells can be efficiently and safely transmitted to the external circuit, maintaining the smooth flow of current in the system.

[0003] The photovoltaic junction box consists of a box body, diodes, and busbars. The diodes are key safety protection components for photovoltaic modules, providing bypass functionality and the ability to prevent reverse discharge. When some cells in a photovoltaic module fail to operate normally due to a fault or external obstruction (such as dark clouds, tree branches, bird droppings, etc.), the diodes connected in parallel to these cells will quickly conduct, isolating them from the main circuit to prevent them from affecting overall power generation efficiency. At the same time, when there is insufficient sunlight (such as at night or on cloudy days) or when the voltage of the external circuit is higher than that of the photovoltaic module, the diodes, with their unidirectional conductivity, can effectively prevent the reverse flow of current (i.e., reverse discharge), thereby protecting the photovoltaic module from damage, extending its service life, and ensuring the stability and reliability of the photovoltaic system.

[0004] However, the current photovoltaic module production process relies on manual labor for the assembly of junction boxes and diodes, a cumbersome process and poor connection stability. In particular, soldering the diodes to the busbars must be performed within the confined space of the junction box, reducing efficiency and increasing the risk of cold solder joints. This directly results in current loss and reduced system efficiency. More seriously, it can cause the diodes' bypass and reverse discharge protection functions to fail. Consequently, failed cells, which should be isolated by the diodes, continue to reduce overall power generation efficiency. Furthermore, when external voltage is excessively high, reverse current cannot be effectively blocked, accelerating damage to the photovoltaic module and shortening its service life. Furthermore, cold solder joints can cause localized overheating and accelerate material degradation, posing a potential threat to the reliability and safety of the entire system. In extreme cases, they can even lead to junction box burns, module combustion, and even serious power plant fires. Utility Model Content

[0005] In view of the problems existing in the prior art, the utility model provides a photovoltaic junction box welding device which is safe, reliable, highly automated and avoids the risk of cold welding.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] A photovoltaic junction box welding device comprises a body, the body is provided with a conveying mechanism, the conveying mechanism is used to send the photovoltaic junction box into and out of the body; a welding mechanism is provided below the conveying mechanism, the welding mechanism is used to weld the bus bar and diode in the photovoltaic junction box together; welding lifting mechanisms are provided on both sides of the welding mechanism, the welding lifting mechanisms are used to adjust the height of the welding mechanism so that the welding nozzle of the welding mechanism can penetrate into the interior of the photovoltaic junction box for accurate and effective welding; the lower end of the lifting mechanism is fixedly arranged on a mobile platform; platform moving mechanisms are installed on both sides of the bottom of the mobile platform, the platform moving mechanism is used to horizontally move the mobile platform and position it directly below the welding position of the photovoltaic junction box, so that the welding nozzle can accurately weld the bus bar and the diode pins together, and can realize the welding of multiple photovoltaic junction boxes in the moving direction; the platform moving mechanism is fixedly arranged on the inner side wall of the body; a tin supply mechanism is also installed on the mobile platform, and the tin supply mechanism provides the welding mechanism with liquid solder required for welding.

[0008] The welding mechanism includes a welding nozzle, a tin supply nozzle and a nozzle bracket; both sides of the nozzle bracket are connected to the welding lifting mechanism, and at least one welding nozzle is arranged on the nozzle bracket.

[0009] The welding nozzle, the tin supply nozzle and the tin supply mechanism are communicated with each other.

[0010] The welding nozzle is composed of two nozzles, which correspond to the two pins of the diode and the two busbar welding positions in the photovoltaic junction box; the top of the nozzle is provided with two nozzles with opposite spray angles, which can effectively fill the weld, increase the welding surface, and reduce tin spraying splashes and eddy currents, thereby improving welding quality and efficiency.

[0011] The top of the nozzle is concave and the periphery is convex, which is used to support the welding surface of the busbar to prevent liquid tin from overflowing from the bottom surface; and is beneficial to forming a good welding joint (welding cap) to ensure that the busbar and the diode are tightly and firmly connected.

[0012] A reflow groove is provided on the periphery of the nozzle, a reflow channel is provided at the bottom of the reflow groove, the reflow channel is connected to a reflow pipe, and the reflow pipe is connected to a tin supply mechanism, so that the liquid solder overflowing during jet welding can flow back to the tin storage tank of the tin supply mechanism from the reflow hole at the bottom of the reflow groove and the reflow pipe, so as to be reused.

[0013] The welding nozzle head is detachably mounted on the nozzle head bracket so that welding nozzle heads of different sizes can be replaced according to different junction box specifications, thereby expanding the applicable scope of the welding device.

[0014] The lifting mechanism is a cylinder, the piston rod of the cylinder is connected to the nozzle bracket, and the welding nozzle is lifted by the pneumatic method of the cylinder, so that the welding nozzle moves up and down, which has the beneficial effects of high efficiency, reliability, softness and environmental protection.

[0015] The platform moving mechanism includes a guide rail, a slider, a gear, a rack, and a drive motor; both ends of the guide rail are fixedly arranged on the inner wall of the body, and the slider is fixedly installed on the bottom of the mobile platform and slides with the guide rail; the guide rail is provided with a rack, and the rotating shaft of the drive motor is equipped with a gear, and the gear is engaged with the rack for transmission; when the drive motor is running, it drives the gear to engage with the rack, so that the mobile platform moves linearly along the length direction of the guide rail, thereby smoothly and accurately positioning the welding mechanism to move it below the photovoltaic junction box.

[0016] The tin supply mechanism includes a tin tank for holding liquid tin or other welding materials, a tin pump for transferring the liquid tin in the tin tank to the welding nozzle, and a heater for melting the solid solder and keeping it in a liquid state; the tin tank is fixedly arranged on the mobile platform; the tin pump inlet is connected to the tin tank, and the tin pump is connected to the tin supply nozzle; the tin pump transfers the liquid tin from the tin supply nozzle to the nozzle of the nozzle to be sent out, so as to weld the pins and bus bars of the diode in the photovoltaic junction box together.

[0017] The tin bath is provided with a detachable cover plate to prevent the liquid tin from splashing out and oxidizing.

[0018] The tin pump is an electromagnetic pump or a mechanical pump; the heater is an electric heating tube, which is laid on the inner wall or outer wall of the tin bath.

[0019] The conveying mechanism includes a feeding conveyor belt and a positioning discharging conveyor belt; the positioning discharging conveyor belt is installed on the conveying frame inside the machine body, and the feeding conveyor belt is installed on the conveying frame outside the machine body.

[0020] The photovoltaic junction box welding device further comprises a controller, which controls the movement position, movement speed and tin spraying amount of each mechanism.

[0021] The machine body is provided with a feed port and a discharge port on two opposite sides respectively. The conveying mechanism delivers the photovoltaic junction box into the machine body from the feed port to ensure that the photovoltaic junction box is welded at the designated welding position; after welding is completed, the conveying mechanism delivers the photovoltaic junction box from the discharge port of the machine body.

[0022] The busbar is an L-shaped busbar, and a tin-filled gap is provided between the busbar and the diode to accommodate liquid tin to form a welding part, thereby eliminating the tinning process. The welding part is thick and strong, effectively avoiding the defects of thin tin at the pre-tinned part of the busbar, loose pressing, and easy detachment and cracking.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. The use of liquid tin nozzles for welding replaces traditional manual soldering irons, reducing labor costs and reducing the safety risks of manual operation; automated flow operations improve production efficiency and operation stability.

[0025] 2. Directly weld the photovoltaic junction box on the photovoltaic module without the need for additional carrier assistance, reducing process steps and speeding up production.

[0026] 3. The welding nozzle adopts two nozzles with opposite spray angles, which not only increases the welding contact surface, reduces the spatter and eddy current phenomenon during the tin spraying process, eliminates the occurrence of false solder joints, and significantly improves the welding quality and reliability.

[0027] 4. The top of the welding nozzle is designed with a concave spherical surface and a convex peripheral structure, which helps to form a round and uniform welding cap during the welding process, further enhancing the beauty and firmness of the welding and improving the overall welding quality.

[0028] 5. The combination of the mobile platform and the lifting mechanism not only solves the technical difficulties of inserting into the photovoltaic junction box for welding and positioning, but also realizes the continuous welding of multiple photovoltaic junction boxes in the moving direction, thus improving production efficiency and operation continuity;

[0029] 6. At the connection between the L-shaped busbar and the diode, the gap filling welding technology is adopted, which eliminates the tedious tinning process and ensures the thickness and firmness of the welding part. It effectively avoids the problems of the tin layer being too thin, not pressed tightly, and easy to crack in the traditional tinning and welding, and significantly improves the strength and stability of the welding joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall design of the utility model;

[0031] Figure 2 This is a schematic diagram of the structure of the utility model

[0032] Figure 3 This is a schematic cross-sectional view of the utility model

[0033] Figure 4 It is a side view schematic diagram of the internal structure of the utility model;

[0034] Figure 5 This is a schematic diagram of the corresponding positions of the utility model welding nozzle and photovoltaic junction box

[0035] Figure 6 This is a schematic diagram of the corresponding positions of the nozzle head with opposite spray angles and the photovoltaic junction box of the utility model

[0036] Figure 7 This is the welding principle diagram of the utility model (opposite spray angle nozzle)

[0037] Figure 8 This is a schematic diagram of the tin flow routing of the double-headed spray nozzle with opposite body angles in this utility model.

[0038] Figure 9 This is a schematic diagram of the structure of the utility model (inorganic body)

[0039] Figure 10 This is a schematic diagram of the structure of the twin nozzle (with reflux groove) of this utility model

[0040] Figure 11 This is a schematic diagram of the principle of the electromagnetic pump of this utility model

[0041] Figure 12 This is a schematic diagram of the position of diodes and busbars in the photovoltaic junction box of this utility model.

[0042] Figure 13 This is a schematic diagram of the utility model photovoltaic junction box busbar and diode after welding

[0043] Markings in the figure: 1. Machine body; 1-1. Machine cover; 2. Conveying mechanism; 2-1. Feed conveyor belt; 2-2. Positioning and discharging conveyor belt; 2-3. Inner conveyor rack; 2-4. Outer conveyor rack; 2-5. Motor; 2-6. Power shaft; 2-7. Drive wheel; 3. Welding mechanism; 3-1. Welding nozzle; 3-1-1. Sub-nozzle; 3-1-1A. Nozzle; 3-1-1B. Concave surface; 3-1-1C. Periphery; 3-1-2. Reflow groove; 3-1-3. Reflow channel; 3-2. Tin supply nozzle; 3-3. Nozzle bracket ;3-1-4, reflux pipe; 4, welding lifting mechanism; 4-1, cylinder; 4-2, piston rod; 5, moving platform; 6, platform moving mechanism; 6-1, guide rail; 6-2, slider; 6-3, gear; 6-4, rack; 6-5, drive motor; 7, tin supply mechanism; 7-1, tin bath; 7-2, tin pump; 8, photovoltaic junction box; 8-1, diode; 8-1-1, diode pin; 8-2, bus bar; 8-2-1, welding hole; 8-3, tin-containing gap; 8-4, solder; 9, photovoltaic module substrate. DETAILED DESCRIPTION

[0044] The specific implementation of the present utility model is described in detail below with reference to the accompanying drawings and examples.

[0045] Example 1 (see Figures 2-4 、 Figures 6-8 、 Figure 11 )

[0046] A photovoltaic junction box welding device comprises a body 1 equipped with a conveying mechanism 2 for transporting a photovoltaic junction box 8 into and out of the body 1. Below the conveying mechanism 2 is a welding mechanism 3 for welding the busbars and diodes within the photovoltaic junction box. Welding mechanisms 3 are flanked by welding lift mechanisms 4 for precise height adjustment. The lower ends of the two welding lift mechanisms 4 are fixed to either side of a mobile platform 5, which is mounted with a tin supply mechanism 7 to provide the liquid solder required for the welding process.

[0047] The welding mechanism 3 includes a welding nozzle 3-1, a tin supply nozzle 3-2 and a nozzle bracket 3-3; both sides of the nozzle bracket 3-3 are connected to the welding lifting mechanism 4, and at least one welding nozzle 3-1 is installed on the nozzle bracket 3-3.

[0048] The welding nozzle 3-1, the tin supply nozzle 3-2 and the tin supply mechanism 7 are connected to each other;

[0049] The welding nozzle 3-1 consists of two sub-nozzles 3-1-1, each of which features two nozzles 3-1-1A at opposite spray angles. This design intersects the fluids ejected from the two nozzles at their intersection. Since the two jet surfaces overlap at this point, the density of the liquid tin in that area increases, resulting in a more even distribution of the liquid tin across the workpiece surface. Furthermore, due to the opposing spray angles, the liquid tin can more extensively cover the workpiece surface after the intersection, creating a larger penetration area. This dispersion facilitates adherence and absorption by the weld surface, preventing direct brushing and tin stripping. Furthermore, the opposing spray angles help reduce spatter and eddy currents during welding. When liquid tin is ejected at a high velocity and directly impacts the workpiece surface, spatter and eddy currents are generated, affecting weld quality. However, when the two opposing jets meet at their intersection, their velocities change direction, reducing the impact force of the direct impact on the workpiece surface and helping to minimize spatter and eddy currents. This achieves uniform distribution and extensive coverage of liquid tin on the workpiece surface, avoids the problems of splashing and eddy currents generated by vertical nozzles, and improves welding quality and efficiency.

[0050] The lifting mechanism 4 is a cylinder 4-1, whose piston rod 4-2 is connected to the nozzle bracket 3-3. The height of the welding nozzle is adjusted by controlling the extension and contraction of the cylinder so that the welding nozzle can extend into the photovoltaic junction box to achieve welding and fixation of the busbar and diode.

[0051] The tin supply mechanism 7 includes a tin tank 7-1, a tin pump 7-2 and a heater. The tin tank 7-1 is used to store liquid tin.

[0052] Tin pump 7-2 uses an electromagnetic pump to extract liquid tin from the tin tank and deliver it to the soldering nozzle 3-1 through the tin supply nozzle 3-2. The electromagnetic pump includes a pump body 7-2-1, an electromagnetic induction device 7-2-2, and a tin spraying tube. Its operating principle is: when a conductive liquid (liquid tin) flows through a magnetic field (pump body), an induced current (i.e., eddy current) is generated in the liquid. This induced current interacts with the magnetic field (pump body) to generate a Lorentz force perpendicular to the direction of liquid flow. This Lorentz force pushes the liquid upward, thereby achieving the effect of tin extraction. It operates based on the principle of electromagnetic induction and has no mechanical seals or rotating parts, so there is no leakage problem. By adjusting the current, the output flow rate can be precisely controlled, with the advantages of compact structure, high efficiency, energy saving and environmental protection.

[0053] The heater uses an electric heating tube to melt the solid solder and maintain the liquid tin at a suitable operating temperature. A tin bath 7-1 is fixedly mounted on the mobile platform 5. The inlet of a tin pump 7-2 is connected to the tin bath 7-1, which in turn is connected to the tin supply nozzle 3-2. The electric heating tube is installed on the inner or outer wall of the tin bath 7-1.

[0054] The welding device also includes a controller for controlling the movement position, speed and tin spraying amount of each mechanism in the welding device to ensure accurate control of the welding process.

[0055] Example 2 (see Figure 7 )

[0056] This embodiment further optimizes the design of the welding nozzle based on the first embodiment. The top of the sub-nozzle 3-1-1 is designed as a concave surface 3-1-1B, and the peripheral edge 3-1-1C is raised. This allows the raised peripheral edge to support the welding surface during welding, preventing liquid solder from overflowing. It also forms a full weld cap in conjunction with the concave surface. This improves welding positioning accuracy and reduces welding defects. The weld joint is plump and beautiful, effectively improving welding quality.

[0057] Example 3 (see Figure 5 、 Figure 10 )

[0058] The present embodiment is different from the previous embodiment in that the nozzle adopts a straight-through structure, and the solder flow is sprayed vertically at the welding point. The sub-nozzle 3-1-1 is provided with a reflow groove 3-1-2 on the periphery, and a reflow channel 3-1-3 is provided at the bottom of the reflow groove. The reflow channel is connected to the reflow pipe 3-1-4, and the reflow pipe 3-1-4 is connected to the tin bath of the tin supply mechanism 7. During welding, the solder is sprayed out in the form of a wave crest through the nozzle of the nozzle, wetting and filling the welding area to achieve welding. The liquid tin overflowing during the welding process falls from the nozzle, enters the reflow groove 3-1-2 on the periphery, flows into the reflow channel 3-1-3, and flows back to the tin bath from the reflow pipe 3-1-4, forming a reused material, reducing the waste of solder and reducing production costs; improving the utilization rate of resources and being beneficial to environmental protection.

[0059] Example 4

[0060] In this embodiment, the welding nozzle 3-1 is detachably mounted on the nozzle holder 3-3 so that a suitable welding nozzle can be selected or replaced according to different workpiece shapes and sizes, thereby improving the flexibility and adaptability of the welding device and reducing the cost of replacing the entire welding device due to changes in the workpiece shape.

[0061] Example 5

[0062] In this embodiment, the tin bath includes a cover plate, on which a soldering nozzle is mounted. The cover plate is removably mounted on the top of the tin bath. This allows for replacement of different cover plates for different processing targets, thereby allowing for the replacement of nozzles. This allows the device to be used for welding various types and quantities of photovoltaic junction boxes.

[0063] Lifting mechanisms are arranged on both sides of the tin bath, and the bottoms of the lifting mechanisms are fixedly arranged on both sides of the moving platform.

[0064] Example 6 (see Figures 2-3 )

[0065] In this embodiment, the conveying mechanism 2 comprises an infeed conveyor belt 2-1 and a positioning and discharging conveyor belt 2-2. The positioning and discharging conveyor belt 2-2 is mounted on a conveyor frame 2-3 inside the machine body 1, while the infeed conveyor belt 2-1 is mounted on a conveyor frame 2-4 outside the machine body 1. The conveyor frame houses a drive assembly comprising a motor 2-5, a power shaft 2-6, a driving pulley 2-7, and a conveyor belt. The motor, via the power shaft, drives the driving pulley, which in turn drives the transmission belt, causing the conveyor belt to circulate. This design of segmented workpiece conveyance inside and outside the machine body offers flexible control, strong adaptability, safety, reliability, and ease of maintenance.

[0066] Example 7 (see Figures 3-4 、 Figure 9 )

[0067] In this embodiment, platform movement mechanisms 6 are mounted on both sides of the bottom of the mobile platform 5 and are fixed to the inner sidewalls of the housing 1. These mechanisms are used to horizontally move the mobile platform 5 directly below the welding location of the photovoltaic junction box, ensuring accurate positioning. This also expands the scope of application, enabling welding of multiple photovoltaic junction boxes in the direction of movement, thereby improving production efficiency and operational consistency.

[0068] The platform moving mechanism 6 includes a guide rail 6-1, a slider 6-2, a gear 6-3, a rack 6-4, and a drive motor 6-5; both ends of the guide rail 6-1 are fixedly arranged on the inner wall of the body 1, and the slider 6-2 is fixedly installed at the bottom of the moving platform 5 and is slidably adapted to the guide rail 6-1; the guide rail 6-1 is provided with a rack 6-4, and a gear 6-3 is installed on the rotating shaft of the drive motor 6-5, and the gear 6-3 is engaged with the rack 6-4 for transmission.

[0069] When the horizontal position of the nozzle needs to be adjusted, the drive motor drives the gear to engage with the rack on the guide rail, driving the slide and the welding device to move the corresponding slider along the length direction of the guide rail. The mobile platform follows the movement, and the nozzle on it moves accordingly, thereby achieving the purpose of positioning movement or continuous welding.

[0070] Example 8 (see Figure 7 、 Figure 13 )

[0071] The busbar 8-2 in the photovoltaic junction box 8 of this embodiment is provided with a welding hole 8-2-1. Its functions and advantages are as follows: 1. A busbar without a welding hole will block the copper pins of the diode, making it impossible to solder the two together by spray welding. The busbar and diode pins can only be soldered together by tinning them first and then hot pressing. The introduction of welding hole 8-2-1 provides a direct and efficient channel for solder, allowing the solder to flow smoothly into and be applied to the diode pins 8-1-1, thereby achieving direct soldering between the busbar and the diode. This not only eliminates the tedious tinning process but also greatly simplifies the production process flow. 2. In the traditional soldering method of tinning first and then pressing, the solder layer is extremely thin and has poor resistance to external forces. When subjected to external impact or vibration, the thin tin layer easily cracks or detaches, causing the connection to fail. Furthermore, compared to the sturdy copper pins, the thin solder layer is also extremely fragile when subjected to stress and deformation. In this embodiment, the ample space in the welding hole 8-2-1 allows the solder to fully flow in and penetrate widely. In addition, the concave spherical surface at the top of the nozzle accommodates the solder, forming a thick and solid welding point, which significantly increases the strength of the welding joint and improves the reliability and durability of the connection. 3. The welding hole 8-2-1 provides a direct channel for the solder, promoting the fluidity and spreadability of the solder, thereby reducing the occurrence of cold solder joints and voids. The solder can more comprehensively cover the contact surface, forming a complete solder layer, and improving the quality of the welded joint. At the same time, the welding hole also helps to reduce the retention of gas between the contact surfaces, further reducing the formation rate of voids, and achieving high-quality welding between the busbar and the diode in the photovoltaic junction box.

[0072] Example 9 (see Figure 7 、 Figure 13 )

[0073] In the photovoltaic junction box 8 of this embodiment, a tin-containing gap 8-3 is provided between the busbar and the diode to accommodate solder, thereby increasing the bonding strength between the two and improving the strength and quality of the solder joint. The principle is as follows: during soldering, the solder delivered by the nozzle is injected into the tin-containing gap between the busbar and the diode pin 8-1-1 through the soldering hole 8-2-1. Under the combined action of surface tension and capillary effect, the solder naturally spreads to form a uniform and dense solder layer. This solder layer not only increases the contact area, but also ensures a firm and tight connection between the diode pin and the busbar by virtue of its good wettability and permeability. At the same time, the solder contained in the concave spherical surface at the top of the nozzle, the solder in the soldering hole 8-2-1, and the solder layer are integrated with each other to form a structurally stable, I-shaped solder joint. This I-shaped weld not only has a larger joint surface area, but also significantly enhances the strength and adhesion of the weld due to its larger thickness and volume. It also fundamentally reduces the occurrence of cold solder joints and voids, effectively improving the connection quality between the busbar and the diode, and providing a solid guarantee for the stable operation of the photovoltaic system.

[0074] Welding process

[0075] 1. Initial placement: Place the photovoltaic junction box 8 (see Figure 12 ) is bonded to the substrate of the photovoltaic module and placed at the starting position of the conveying mechanism 2, ready for transportation.

[0076] 2. Conveying and positioning: The controller activates conveying mechanism 2, and the photovoltaic junction box is smoothly and accurately conveyed along the preset track into the interior of the machine body 1 until it reaches the welding position. At this time, the controller instructs conveying mechanism 2 to stop.

[0077] 3. Welding preparation: At the same time, the controller starts the platform moving mechanism 6, drives the moving platform 5 to move the welding nozzle 3-1 of the welding mechanism 3 to a position just below the junction box.

[0078] 4. Precise docking: The controller activates the lifting mechanism 4 to lift the welding nozzle 3-1 into the photovoltaic junction box, ensuring that the two sub-nozzles 3-1-1 are accurately aligned with the positive and negative pins 8-1-1 of the diode 8-1, and their peripheral edges 3-1-1C are against the busbar welding hole 8-2-1. (See 7)

[0079] 5. Welding execution: The controller starts the tin pump 7-2, which draws liquid tin from the tin tank 7-1, feeds it into the tin supply nozzle 3-2, and injects it into the welding hole 8-2-1 of the bus bar 8 through the nozzle of the sub-nozzle 3-1-1, and flows into the tin-containing gap 8-3 between the bus bar 8 and the diode pin 8-1-1, and quickly penetrates and fills the gap, forming a solder layer platform, firmly connecting the bus bar 8 and the diode pin 8-1-1 together.

[0080] During this process, the controller precisely controls the output flow rate and soldering stop timing of solder pump 7-2. By finely adjusting the pumping rate and duration, the controller ensures the correct amount of solder is injected, preventing excessive solder from overflowing the joint and insufficient solder from affecting solder quality. Simultaneously, the controller stops the solder pump at the exact moment the nozzle separates from the solder joint. By leveraging the concave surface of the nozzle tip, the inherent tension of the solder, and its cooling contraction, the solder forms a naturally rounded, tail-free solder cap at the joint. This improves the aesthetics of the solder joint and enhances the reliability and stability of the weld.

[0081] 6. After welding is completed and reset: After welding is complete, the tin supply mechanism 7 automatically stops. The controller activates the lifting mechanism 4, returning the welding mechanism 3 to its initial height in preparation for the next welding cycle. Simultaneously, the moving mechanism 6 is activated to adjust the mobile platform 5 back to its initial position as needed or to prepare for the next photovoltaic junction box to be welded.

[0082] 7. Continue conveying: The control mechanism restarts conveying mechanism 2, which delivers the completed PV junction box from the welding position out of the machine body 1 and prepares to receive the next PV junction box to be welded. The entire welding process is automated and continuous, significantly improving production efficiency and welding quality.

Claims

1. A photovoltaic junction box welding device, characterized in that: The invention comprises a machine body (1), wherein the machine body (1) is provided with a conveying mechanism (2), and the conveying mechanism (2) is used to convey a photovoltaic junction box (8) into and out of the machine body (1); a welding mechanism (3) is provided below the conveying mechanism (2), and the welding mechanism (3) is used to weld the bus bar and the diode in the photovoltaic junction box together; welding lifting mechanisms (4) are provided on both sides of the welding mechanism (3), and the welding lifting mechanisms (4) are used to adjust the height of the welding mechanism (3); the lower end of the welding lifting mechanism (4) is fixedly arranged on a mobile platform (5); platform moving mechanisms (6) are installed on both sides of the bottom of the mobile platform (5), and the platform moving mechanisms (6) are used to move the mobile platform (5) horizontally to the position directly below the welding position of the photovoltaic junction box; the platform moving mechanism (6) is fixedly arranged on the inner side wall of the machine body (1); a tin supply mechanism (7) is also installed on the mobile platform (5), and the tin supply mechanism (7) provides the welding mechanism (3) with liquid solder required for welding; The welding mechanism (3) comprises a welding nozzle (3-1), a tin supply nozzle (3-2) and a nozzle bracket (3-3); both sides of the nozzle bracket (3-3) are connected to the welding lifting mechanism (4), and at least one welding nozzle (3-1) is provided on the nozzle bracket (3-3); The welding nozzle (3-1), the tin supply nozzle (3-2) and the tin supply mechanism (7) are in communication with each other; The welding nozzle (3-1) is composed of two sub-nozzles (3-1-1), and the top of the sub-nozzle (3-1-1) is provided with two nozzles (3-1-1A) with opposite spraying angles.

2. The photovoltaic junction box welding device according to claim 1, characterized in that: The top of the sub-nozzle (3-1-1) is a concave surface (3-1-1B), and the peripheral edge (3-1-1C) is convex.

3. The photovoltaic junction box welding device according to claim 1, characterized in that: A reflux groove (3-1-2) is provided on the periphery of the sub-nozzle (3-1-1), a reflux channel (3-1-3) is provided at the bottom of the reflux groove, the reflux channel is connected to a reflux pipe (3-1-4), and the reflux pipe (3-1-4) is connected to a tin supply mechanism (7).

4. The photovoltaic junction box welding device according to claim 1, characterized in that: The welding nozzle (3-1) is detachably mounted on the nozzle bracket (3-3).

5. The photovoltaic junction box welding device according to any one of claims 1 to 4, characterized in that: The lifting mechanism (4) is a cylinder (4-1), and the piston rod (4-2) of the cylinder (4-1) is connected to the nozzle bracket (3-3).

6. The photovoltaic junction box welding device according to any one of claims 1 to 4, characterized in that: The platform moving mechanism (6) comprises a guide rail (6-1), a slider (6-2), a gear (6-3), a rack (6-4), and a driving motor (6-5); both ends of the guide rail (6-1) are fixedly arranged on the inner wall of the machine body (1); the slider (6-2) is fixedly installed on the bottom of the moving platform (5) and is slidably adapted to the guide rail (6-1); the guide rail (6-1) is provided with a rack (6-4); a gear (6-3) is installed on the rotating shaft of the driving motor (6-5); the gear (6-3) and the rack (6-4) are meshed and transmitted.

7. The photovoltaic junction box welding device according to any one of claims 1 to 4, characterized in that: The tin supply mechanism (7) comprises a tin tank (7-1) for containing liquid tin or welding material, a tin pump (7-2) for transferring the liquid tin in the tin tank (7-1) to the welding nozzle (3-1), and a heater for melting the solid solder and keeping it in a liquid state; the tin tank (7-1) is fixedly arranged on the mobile platform (5); the inlet of the tin pump (7-2) is connected to the tin tank (7-1), and the tin pump (7-2) is connected to the tin supply nozzle (3-2).

8. The photovoltaic junction box welding device according to claim 7, characterized in that: The tin pump (7-2) is an electromagnetic pump or a mechanical pump; the heater is an electric heating tube, which is laid on the inner wall or outer wall of the tin bath (7-1).

9. The photovoltaic junction box welding device according to any one of claims 1 to 4, characterized in that: The conveying mechanism (2) comprises a feeding conveyor belt (2-1) and a positioning discharging conveyor belt (2-2); the positioning discharging conveyor belt (2-2) is installed on a conveying frame (2-3) inside the machine body (1), and the feeding conveyor belt (2-1) is installed on a conveying frame (2-4) outside the machine body (1).

10. The photovoltaic junction box welding device according to any one of claims 1 to 4, characterized in that: The device also includes a controller, which controls the movement position, movement speed and tin spraying amount of each mechanism in the device.

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