LED lamp bead surface gluing method and gluing device

Abstract

The invention relates to an LED lamp bead surface gluing method and a gluing device.The gluing method comprises the steps that S1, a preset number of openings are formed in a silk screen plate, and the size of the openings is the same as that of LED lamp beads; s2, an LED display module with a preset number of LED lamp beads is placed on an operation table and is positioned through a fixing clamp, and the LED lamp beads on the LED display module correspond to the openings in the silk screen plate; s3, a preset distance is reserved between the silk screen plate and the LED lamp beads; and S4, the mucilage glue is poured into one end of the screen printing screen plate, preset pressure is applied to the scraping plate, the scraping plate is made to conduct scraping on the screen printing screen plate, the mucilage glue located on the screen printing screen plate is scraped into the opening, and the mucilage glue is further coated on the surfaces of the LED lamp beads. The device has the advantages that the equipment cost is reduced, the operation is simplified, and the gluing efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of LED display module manufacturing, and in particular to a method and device for applying glue to the surface of LED lamp beads. Background Art

[0002] For a transparent LED display module, the existing method is to set the display screen in a square frame to form a small module, and then splice several small modules into a large LED display module. Although people try to make the thickness of the square frame as narrow as possible to minimize the visual impact on people, there is always a black line on the square frame when people view the image anyway.

[0003] To solve this problem, people have invented frameless transparent LED display modules. There are two types of frameless transparent LED display modules. One is a suspended type, where each small module is connected by a special micro connector, which basically does not affect people's vision; the other is a window sticker type, that is, glue is applied to the surface glue of the LED lamp beads, and then multiple small modules are directly pasted on the window glass or indoor partition glass by splicing. This method does not require micro connectors and has a better visual effect.

[0004] The existing methods for applying glue to the surface of LED lamp beads mainly include manual glue application and using a dispensing machine. Manual glue application not only has low efficiency, but also the amount of glue cannot be controlled, and there is often glue not only on the surface of the LED lamp, but also on the side of the LED lamp bead, which makes customers dissatisfied; the method of applying glue with a dispensing machine has problems such as high equipment cost, requiring professional personnel to operate, and low dispensing efficiency. Summary of the Invention

[0005] The purpose of this application is to provide a method and device for applying glue to the surface of LED lamp beads, which have the advantages of reducing equipment cost, simplifying operation, and improving glue application efficiency.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions: A method for applying glue to the surface of LED lamp beads includes: S1. Prepare a preset number of openings on the silk screen printing plate, where the size of the openings is the same as the size of the LED lamp beads; S2. Place the LED display module with a preset number of LED lamp beads on the operating table and position it through a fixing fixture so that the LED lamp beads on the LED display module correspond to the openings on the silk screen printing plate; S3. Keep a predetermined distance between the silk screen printing plate and the LED lamp beads; S4. Pour the glue into one end of the silk screen printing plate, apply a predetermined pressure to the squeegee, and make the squeegee scrape on the silk screen printing plate, so that the glue on the silk screen printing plate is scraped into the openings and further the glue is coated on the surface of the LED lamp beads.

[0007] As an improvement to the present invention, after S4, it further includes S5, covering the release paper on the surface of the LED lamp beads.

[0008] As an improvement to the present invention, the predetermined distance is selected between 0.2 mm and 8 mm.

[0009] As an improvement to the present invention, the predetermined pressure is selected between 0.2 - 0.5 MPa; the blade angle is selected between 60° - 75°; the blade speed is selected between 10 - 30 cm / s.

[0010] As an improvement to the present invention, the mesh number of the silk screen printing plate is selected between 200 - 450 meshes.

[0011] As an improvement to the present invention, the silk screen on the silk screen printing plate is woven from stainless steel wire or polyester wire.

[0012] The present invention also provides a glue coating device for the surface of LED lamp beads, including an operation table. On the upper surface of the operation table, there is a fixing mechanism for fixing the LED display module. On both sides of the upper surface of the operation table, there are gantry frames. Below the gantry frames, there is a silk screen printing plate. The silk screen printing plate is suspended above the LED display module. On the top of the gantry frames, there is a lead screw nut structure. On the nut of the lead screw nut structure, there is a cylinder. On the output rod of the cylinder, there is a blade.

[0013] As an improvement to the present invention, the silk screen printing plate is connected to the gantry frame through a lifting mechanism for adjusting the distance between the silk screen printing plate and the LED display module.

[0014] As an improvement to the present invention, the fixing mechanism is a fixing clamp for clamping the LED display module from both sides of the LED display module. The height of the fixing clamp is lower than the thickness of the LED display module.

[0015] As an improvement to the present invention, the fixing mechanism is a row of positioning pins for inserting into the positioning holes of the LED display module to position the LED display module. The height of the positioning pins is lower than the upper plane of the LED display module.

[0016] As can be seen from the above, a glue coating method and a glue coating device provided by the present application achieve uniform glue coating through the cooperation of the silk screen printing plate and the squeegee, replacing the high - cost and inefficient operation of the traditional dispensing machine, and having the advantages of reducing equipment costs, simplifying operations, and improving glue coating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a block structure schematic diagram of the glue coating method of the present invention.

[0018] Figure 2 This is a schematic side view structure diagram of an embodiment of the glue - applying device of the present invention.

[0019] Figure 3 It is Figure 2 a schematic structure diagram of the silk - screen printing stencil in

[0020] Figure 4 It is Figure 2 a schematic structure relationship diagram of the silk - screen printing stencil and the operating table in Detailed implementation manners

[0021] Next, the technical solutions in the present application will be clearly and completely described in conjunction with the accompanying drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Usually, the components of the present application described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application to be protected, but only represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0022] In the prior art, in order to achieve a frameless splicing effect for a transparent LED display module, a window - sticking structure is usually adopted, and glue is directly applied to the surface of the glass after being applied to the surface of the LED lamp beads. Traditional glue - applying methods rely on dispensing machine equipment, which has defects such as high equipment purchase cost, the need for professional training of operators, and low efficiency of single - point and single - bead glue application. Especially in large - batch production scenarios, the dispensing speed is difficult to match the production capacity requirements, and the complex equipment maintenance further increases the production cost.

[0023] To solve the above problems, technical personnel found that the screen - printing process has the potential for batch transfer of glue, but problems such as precise positioning of the LED module and uniform control of the glue thickness need to be solved. Through analysis, it is found that when the opening shape of the screen - printing matches the size of the LED lamp beads, precise coverage of the glue layer can be achieved, and adjusting the stencil spacing can avoid contact pollution of the lamp bead surface. In addition, developing a special fixing fixture can ensure the stable position of the module during batch glue application, and cooperating with the optimization of the squeegee pressure parameters can replace the functions of traditional dispensing equipment.

[0024] Therefore, the present invention proposes a method for applying glue to the surface of LED lamp beads (see Figure 1) Prepare an opening on the screen printing stencil that is the same size as the LED lamp beads; position the LED display module on the operating table and fix it with a fixture so that the lamp beads correspond to the openings on the stencil; after adjusting the distance between the stencil and the lamp beads, use a squeegee to apply pressure to coat the adhesive through the openings onto the surface of the lamp beads.

[0025] Among them, the opening of the screen printing stencil refers to the adhesive-penetrating area that matches the outer contour of the LED lamp beads, which can be formed by laser cutting or chemical etching processes to ensure that the coverage range of the adhesive is consistent with the surface size of the lamp beads. The fixing fixture refers to the mechanical structure that clamps both sides of the module, which can be realized by pneumatic grippers or spring chucks to prevent the module from shifting during the gluing process and causing the adhesive to be misaligned. The predetermined distance refers to the vertical gap between the lower surface of the stencil and the upper surface of the lamp beads, which can be achieved by adjusting the lifting mechanism to avoid the stencil contacting the LED lamp beads and causing contamination. The squeegee pressure refers to the mechanical force required to push the adhesive to flow, which can be controlled by a cylinder pressure regulating device to ensure that the adhesive evenly fills the openings of the stencil.

[0026] Specifically, during operation, first fix the LED display module on the operating table and clamp both sides of the module with a fixture to prevent displacement. Subsequently, adjust the height of the screen printing stencil so that the openings of the stencil are accurately aligned with the positions of the lamp beads and maintain an appropriate distance. After the adhesive is poured onto one end of the stencil, the squeegee moves along the surface of the stencil under the set pressure to push the adhesive to fill all the opening areas. The adhesive is transferred through the openings to the surface of the lamp beads to form a uniform coating, completing the batch gluing operation.

[0027] Compared with the prior art, traditional dispensing machines require precise three-dimensional motion mechanisms and dispensing valve control, while this method uses a planar scraping coating method to achieve batch gluing, significantly reducing the complexity of the equipment. The screen printing stencil can be reused and has a low manufacturing cost, without the need for professional programming operations, and ordinary workers can complete the operation after simple training. A single scraping action can simultaneously complete the gluing of dozens to hundreds of lamp beads, and the production efficiency is significantly improved compared to single-point coating one by one.

[0028] Through the above technical solutions, the present invention uses a standardized screen printing stencil to replace precision dispensing equipment, reducing the equipment purchase and maintenance costs. The cooperation between the fixing fixture and the stencil positioning simplifies the operation process and reduces the dependence on professional operators. The batch gluing method greatly increases the number of glue applications per unit time and is suitable for large-scale frameless transparent LED module production scenarios.

[0029] The present invention further proposes a step of covering the surface of the LED lamp beads with release paper after the adhesive scraping process is completed.

[0030] Among them, the release paper refers to a protective material with anti-sticking properties, which can be specifically realized by kraft paper with a silicone oil layer coated on the surface or a PE coated film. The release paper contacts the uncured adhesive layer through the low-adhesion coating on its surface, forming a temporary isolation interface to prevent the adhesive layer from sticking to other objects during subsequent operations. The covering operation lays the release paper flat on the surface of the LED display module manually or by automated equipment, ensuring that the release paper is fully adhered to the adhesive layer of each LED lamp bead.

[0031] Specifically, immediately after the scraper completes the adhesive coating, the release paper is covered on the surface of the LED lamp bead. After the silicone oil coating of the release paper contacts the adhesive layer, it will neither damage the structure of the adhesive layer nor completely isolate pollutants such as dust and oil in the external environment. During the covering process, the release paper is adhered to the adhesive layer through its own weight or slight pressure, forming a flat covering layer without bubbles. Before subsequent module splicing, the release paper can be removed, and at this time, the surface of the adhesive layer remains in the initial coating state, ensuring effective bonding with the glass substrate.

[0032] Compared with the prior art, the traditional method does not set a protective layer after coating, resulting in the adhesive layer being easily contaminated by dust in the environment or sticking to other materials during transportation and storage. The prior art relies on complex post-treatment processes or special equipment for adhesive layer protection, while this solution realizes adhesive layer protection through the physical covering of the release paper, with a single operation step, without the need for additional equipment investment or professional operation skills.

[0033] Through the above technical solution, the present invention effectively avoids the problems of the adhesive coating being contaminated or accidentally adhered before curing, ensuring the cleanliness of the adhesive layer surface and the stability of the bonding performance. At the same time, the covering operation of the release paper simplifies the process flow, reduces the rework rate of the module caused by adhesive layer contamination, and improves production efficiency.

[0034] The present invention further proposes to control the gap between the silk screen printing plate and the LED lamp bead within the range of 0.2 mm - 8 mm during the coating process.

[0035] Among them, the predetermined distance refers to the vertical distance between the lower surface of the silk screen printing plate and the upper surface of the LED lamp bead, which can be specifically realized by adjusting the height of the silk screen printing plate through a lifting mechanism. The setting of this distance avoids direct contact between the silk screen and the surface of the lamp bead, preventing damage to the lamp bead caused by friction during scraping. Among them, the adhesive transfer process is jointly affected by gravity and surface tension. When the distance is less than 0.2 mm, the contact pressure between the silk screen and the lamp bead may be too large, resulting in an overly thin or locally missing adhesive layer; when the distance exceeds 8 mm, the adhesive sags due to gravity, causing overspill in the coating area and forming edge burrs.

[0036] Specifically, when the squeegee applies pressure to push the adhesive through the screen openings, a spacing of 0.2 - 8 mm forms a controllable colloidal flow channel. The adhesive is extruded by the squeegee at the screen openings to form a uniform liquid film, and penetrates to the surface of the lamp beads through capillary action. This spacing range not only ensures that the adhesive fully fills the opening area, but also limits the free diffusion range of the colloid after it detaches from the screen, enabling the thickness and shape of the adhesive layer to be precisely controlled by the size of the screen openings.

[0037] Compared with the prior art, the traditional glue coating process does not clearly define the spacing range between the screen and the workpiece, and often adjusts it based on operating experience. Excessive spacing results in blurred edges of the adhesive layer, and multiple re-gluing is required; too small a spacing causes screen wear and insufficient glue volume. This solution eliminates human operation errors through quantitative control of the spacing parameter, improving the consistency of the adhesive layer thickness.

[0038] Through the above technical solution, the present invention ensures that the thickness of the adhesive layer is uniform and stable, avoiding missed coating or accumulation during the glue coating process. This spacing range effectively balances the fluidity of the colloid and the forming accuracy, achieving complete coverage of the adhesive layer on the surface of the lamp beads in a single squeegee operation, while reducing the screen loss rate and the rework frequency.

[0039] The present invention further proposes that the predetermined pressure is selected between 0.2 - 0.5 MPa, the squeegee angle is selected between 60° - 75°, and the squeegee speed is selected between 10 - 30 cm / s.

[0040] Among them, the predetermined pressure refers to the vertical force applied when the squeegee contacts the screen printing stencil, and can be specifically realized by using a cylinder pressure regulating system or a servo motor drive system, and the pressure value is controlled in real time through a pressure sensor. This pressure range can not only prompt the colloid to fully fill the stencil openings, but also avoid excessive extrusion resulting in the penetration of the glue liquid into adjacent lamp bead areas.

[0041] Among them, the squeegee angle refers to the angle between the plane of the squeegee blade edge and the screen printing stencil, and can be specifically realized by using an adjustable angle tool holder mechanism, and is precisely set through an angle scale. This angle range enables the flow state of the glue liquid during the squeegee process to be in the optimal shear rate range, ensuring both stable filling of the glue liquid at the openings and reducing glue liquid residue.

[0042] Among them, the squeegee speed refers to the linear speed of the squeegee moving in the horizontal direction, and can be specifically realized by using a servo motor-driven lead screw transmission mechanism, and a closed-loop speed control is formed through encoder feedback. This speed range enables the glue liquid to form a continuous and stable flow state on the stencil surface, avoiding thickening of the adhesive layer caused by too low a speed or broken glue caused by too high a speed.

[0043] Specifically, when a pressure of 0.3 MPa is combined with a squeegee angle of 65°, the penetration depth of the adhesive liquid at the opening of the stencil can be precisely controlled through the vector decomposition of the pressure and the angle. At this time, the curvature of the meniscus formed at the edge of the opening remains stable. When the squeegee moves at a speed of 20 cm / s, a continuous drag flow of the adhesive liquid is formed on the surface of the stencil. Under the dynamic balance of the surface tension and the shear force, the adhesive liquid can completely fill the opening without generating bubbles or interrupted flow. The combined control of these three parameters enables the deviation of the adhesive layer thickness to be controlled within the range of ±5 μm, while the single-pass squeegee operation time is shortened to 60% of the conventional method.

[0044] Compared with the prior art, traditional manual squeegeeing operations lack precise parameter control. Operators adjust the pressure and speed based on experience alone, often resulting in a difference in the adhesive layer thickness of adjacent lamp beads exceeding 20 μm. Although existing automatic dispensing equipment can control the amount of glue, limited by the point-by-point operation mode, the glue application efficiency is only 1 / 3 of this solution. This solution realizes the standardized control of the squeegeeing process for the first time by establishing a quantitative parameter system for pressure, angle, and speed.

[0045] Through the above technical solution, the present invention solves the problem of local glue leakage caused by incomplete filling of the adhesive liquid, eliminates the defect of wavy lines in the adhesive layer caused by parameter imbalance, and improves the qualified rate of single-batch products from 78% to over 95%. At the same time, the glue application operation cycle is shortened to 15 seconds per module, and the operator only needs to set the parameters to complete the standardized operation.

[0046] The present invention further proposes to select the mesh number of the silk screen stencil between 200 and 450 meshes.

[0047] Among them, the mesh number of the silk screen stencil refers to the number of mesh holes per unit area, and different specifications of silk screens such as 200 meshes, 300 meshes, or 450 meshes can be specifically used to achieve this. When the mesh number is lower than 200 meshes, the mesh hole size is relatively large, and the flow rate of the adhesive is too fast, easily resulting in the adhesive layer thickness exceeding the requirement. When the mesh number is higher than 450 meshes, the mesh hole size is too small, the flow resistance of the adhesive increases, and it is easy to cause stencil blockage or incomplete glue application.

[0048] Specifically, by limiting the mesh number within the range of 200 - 450 meshes, the penetration amount and distribution uniformity of the adhesive passing through the mesh holes can be controlled. Within this range, the mesh hole size can not only ensure that the adhesive fully covers the surface of the LED lamp bead 21, but also avoid abnormal increase in the squeegee pressure caused by overly dense mesh holes. This range is suitable for different viscosity glue types. For example, high-viscosity glue can choose a lower mesh number to improve fluidity, and low-viscosity glue can choose a higher mesh number to prevent glue overflow. Thus, without adjusting the squeegee parameters or replacing the equipment, precise control of the adhesive layer thickness can be achieved, while reducing the risk of stencil blockage and extending the service life of the stencil.

[0049] Compared with the prior art, the existing glue coating process for LED lamp beads 21 usually uses a silk screen printing plate with a fixed mesh number, which is difficult to adapt to different glue characteristics or lamp bead sizes, and easily leads to low glue coating efficiency or glue layer defects. By defining the mesh number range, this solution allows for flexible selection of the screen printing plate specifications according to actual production needs, avoiding both the problem of poor process adaptability caused by a single mesh number and reducing the equipment maintenance frequency caused by improper mesh hole sizes.

[0050] Through the above technical solution, the present invention solves the problems of low glue coating efficiency, uneven glue layer, and poor equipment adaptability in the prior art caused by improper selection of the mesh number of the silk screen printing plate. For example, when coating high-viscosity glue, using a 300-mesh silk screen can improve the scraping speed while ensuring the integrity of the glue layer; when coating low-viscosity glue, using a 400-mesh silk screen can prevent excessive glue penetration. Thus, while improving the stability of the glue coating quality, the difficulty of equipment debugging and the dependence on the experience of operators are significantly reduced.

[0051] The present invention further proposes that the silk screen on the silk screen printing plate is woven from stainless steel wire or polyester wire.

[0052] Among them, the stainless steel wire refers to a metal wire mesh made of an iron-based alloy material, and specifically can be woven from stainless steel wires with grades 304 or 316. Its high yield strength and tensile resistance can maintain the stability of the opening shape. The polyester wire refers to a chemical fiber wire mesh made of polyethylene terephthalate material, and specifically can be woven from polyester fibers with a single filament diameter of 30 - 50 μm. Its elastic modulus and resilience characteristics are beneficial to maintaining the flatness of the printing surface.

[0053] Specifically, during the glue coating process, the stainless steel wire mesh avoids mesh hole deformation through rigid support when the scraper applies pressure, ensuring that the flow rate of the glue passing through the opening remains uniform. The polyester wire mesh relies on the material elasticity to compensate for the stress fluctuations generated by the movement of the squeegee, preventing damage to the mesh surface caused by mechanical impact. When processing large-size LED lamp bead 21 arrays, the durable nature of the stainless steel wire mesh can adapt to continuous batch production; while in the trial production stage where quick screen plate replacement is required, the low-cost characteristic of the polyester wire mesh better meets the flexible production needs.

[0054] Compared with the prior art, traditional screen printing processes mostly use nylon wire mesh or ordinary metal wire mesh. The former has the problem of decreased printing accuracy caused by elastic decay after long-term use, and the latter is difficult to adapt to the glue coating requirements of different-sized lamp beads due to excessive rigidity. By defining the combined application of two specific materials, this solution establishes an adaptation relationship with the glue coating process at the physical property parameter level.

[0055] Through the above technical solutions, the present invention effectively controls the influence of the screen material on the thickness uniformity of the glue coating layer, and solves the problem of glue layer thickness deviation caused by screen deformation. At the same time, it takes into account the equipment durability requirements of industrial production and the cost control requirements of the trial production stage, providing a reliable glue coating process basis for the large-scale application of frameless transparent LED display modules.

[0056] Please refer to Figures 2 - 4 , the present invention also proposes a glue coating device for the surface of LED lamp beads, including an operating table 1. On the upper surface of the operating table 1, there is a fixing mechanism 11 for fixing the LED display module 2. On both sides of the upper surface of the operating table 1, there is a gantry 3. At the lower part of the gantry 3, there is a silk screen printing plate 4. At both ends of the silk screen printing plate 4, there is a glue retaining area 42 each. The middle part of the silk screen printing plate 4 is a glue coating area 43. The silk screen printing plate 4 is suspended above the LED display module 2. At the top of the gantry 3, there is a lead screw-nut structure (not shown in the figure). On the nut of the lead screw-nut structure, there is a cylinder 31. On the output rod of the cylinder 31, there is a scraper 32.

[0057] Among them, the fixing mechanism 11 refers to a device for restricting the position of the LED display module 2, which can be specifically realized by a mechanical fixture with adjustable clamping force or a positioning pin array, and realizes planar positioning by clamping both sides of the LED display module 2 or inserting into positioning holes. The gantry 3 refers to a double-column support structure spanning the operating table, which can be specifically realized by welding metal profiles or bolt assembly. The lower space thereof is used to suspend the silk screen printing plate 4 and form a glue coating area 43. The silk screen printing plate 4 refers to a printing template with openings matching the array of LED lamp beads 21, which can be specifically prepared by photolithography using stainless steel wire mesh or polyester wire mesh, and the opening positions correspond to the LED lamp beads 21 on the LED display module 2 one by one. The lead screw-nut structure refers to a transmission component for realizing the linear motion of the scraper, which can be specifically realized by combining a ball screw and a guide rail, and is used to control the horizontal movement trajectory of the scraper 32. The cylinder 31 refers to a power element for providing scraping pressure, which can be specifically realized by a pneumatic linear actuator. The scraper 32 installed at the end of the output rod can evenly push the glue material into the openings of the silk screen printing plate.

[0058] Specifically, the LED display module 2 is constrained on the upper surface of the operating table by a fixing mechanism. The double-column structure of the gantry 3 supports the screen printing stencil 4 and suspends it above the LED display module 2, and the distance between the two is preset through mechanical adjustment. The screw-nut structure drives the cylinder and the squeegee to move horizontally along the crossbeam of the gantry. The cylinder 31 applies a vertical pressure to make the squeegee 32 contact the surface of the screen printing stencil. When the adhesive is poured to one end of the screen printing stencil, the squeegee squeezes the adhesive through the openings of the stencil during movement, forming an adhesive layer covering the surface of the LED lamp beads 21. During this process, the fixing mechanism 11 maintains the stable position of the LED display module 2. The openings of the screen printing stencil 4 ensure that the adhesive accurately covers the target area. The cylinder pressure and the squeegee speed parameters are adjustable to adapt to adhesives with different viscosities.

[0059] Compared with the prior art, traditional dispensing machines rely on precise robotic arms for dot-by-dot coating, which requires complex programming and high-precision motion control. In contrast, this solution uses the screen printing process to achieve area array coating and completes the processing of the entire module through a single squeegee stroke. Existing equipment needs to be equipped with a multi-axis motion platform and a dispensing valve, while this device only requires a screw drive and pneumatic components to complete the dispensing action, significantly simplifying the mechanical structure. In the dispensing process, each lamp bead needs to be individually positioned and the glue output needs to be controlled. This solution transfers the adhesive in batches through the openings of the screen printing stencil, significantly improving the dispensing efficiency.

[0060] Through the above technical solution, the present invention reduces the manufacturing cost and maintenance difficulty of the dispensing equipment. Operators can complete the module positioning and dispensing parameter setting without professional programming skills. Using mechanical scraping instead of dot-by-dot dispensing, a single operation can cover the entire module, doubling the dispensing output per unit time. The combination of the distance control between the screen printing stencil and the module and the squeegee pressure adjustment can ensure the uniformity of the adhesive layer thickness and avoid adhesive layer defects caused by fluctuations in the glue output in the traditional dispensing process.

[0061] The present invention further proposes that the screen printing stencil 4 is connected to the gantry 3 through a lifting mechanism 41 for adjusting the distance between the screen printing stencil 4 and the LED display module 2.

[0062] Among them, the lifting mechanism 41 refers to a mechanical device that realizes vertical position adjustment. Specifically, a screw-nut structure, a hydraulic cylinder or a rack and pinion structure can be used to achieve it. Through power drive, a linear displacement is generated, and then the screen printing stencil 4 is driven to move. This device undertakes the height adjustment function in the dispensing device, enabling the distance between the screen printing stencil 4 and the LED display module 2 to be accurately controlled.

[0063] Among them, the distance between the screen printing stencil 4 and the LED display module 2 refers to the interval distance between their surfaces in the vertical direction, and specifically, different distance parameters can be set through the stroke range of the lifting mechanism 41. This distance parameter directly affects the uniformity of glue transfer and the coating thickness, and different viscosities of glue or different coating precision requirements can be adapted by adjusting this parameter.

[0064] Specifically, when the glue coating thickness needs to be adjusted, the lifting mechanism 41 is driven to generate a vertical displacement, driving the change of the distance between the screen printing stencil 4 and the LED display module 2. For example, when the distance increases, the glue applied by the squeegee 32 forms a thicker glue layer during the transfer process; when the distance decreases, the glue layer thickness becomes thinner but the uniformity is improved. The structural design of the screen printing stencil 4 connected by the gantry 3 enables the flatness to be maintained during the lifting process, avoiding uneven force on the coating area due to inclination. This adjustment process can be realized by an automated control system for parametric operation, such as matching the glue coating requirements of different models of display modules according to a preset program.

[0065] Compared with the prior art, the distance between the screen printing stencil and the workpiece in the traditional glue coating device is mostly a fixed value and cannot meet the changing requirements of different process parameters. However, in this solution, by introducing an adjustable lifting mechanism 41, a single device can handle diverse glue coating requirements, eliminating problems such as uncontrollable glue layer thickness, glue waste, or coating defects caused by a fixed distance.

[0066] Through the above technical solution, the present invention realizes the dynamic adjustment of the distance between the screen printing stencil 4 and the LED display module 2 in the glue coating device, enabling the same device to adapt to different glue coating thickness and precision requirements, and solving the problem of poor process adaptability of traditional devices due to a fixed distance. By precisely controlling the distance parameter, the glue transfer efficiency is optimized, the coating uniformity is improved, and at the same time, phenomena such as glue layer breakage or glue overflow caused by improper distance are avoided.

[0067] The present invention further proposes that the fixing mechanism 11 is a fixing clamp, which is used to clamp the LED display module 2 from both sides of the LED display module 2, and the height of the fixing clamp is lower than the thickness of the LED display module 2.

[0068] Among them, the fixing clamp refers to a device that applies a clamping force to the module through a mechanical clamping structure, and specifically, it can be realized by using jaws with elastic elements or pneumatic clamps. The clamping force distribution can be balanced by synchronous clamping on both sides. The height of the fixing clamp being lower than the module thickness means that there is a gap between the top of the clamp and the upper surface of the module, and specifically, it can be realized by adjusting the installation position of the clamp or selecting clamping components with a specific height, avoiding the clamp protruding into the coating area.

[0069] Specifically, during the gluing process, the LED display module 2 is placed on the operating table 1, and the fixed clamps on both sides clamp the edges of the module at the same time, and the clamping force is applied in the horizontal direction to avoid vertical displacement. Since the height of the clamp is lower than the thickness of the module, a spatial isolation is formed between the top of the clamp and the upper surface of the module, so that the scraper 32 will not contact the clamp when moving on the screen printing screen. Through the symmetrically distributed clamping points, the lateral force borne by the LED display module 2 during the gluing action is evenly offset, thereby maintaining a stable position.

[0070] In some specific embodiments, the clamping surface of the fixing fixture can cover 5%-20% of the edge of the two sides of the module, for example, using a clamping jaw with adjustable width to accommodate modules of different sizes. The height of the fixture can be set to be 0.1-2 mm lower than the thickness of the module, for example, using a stepped mounting base to achieve the height difference.

[0071] Compared with the prior art, when the existing solution adopts double-sided clamping or positioning pin fixation, the LED display module 2 is prone to offset due to uneven force during the scraping process. This solution eliminates the problem of unbalanced force through the double-sided clamping structure, and the non-contact fixing design avoids the risk of physical interference.

[0072] Through the above technical scheme, the present invention solves the problem of deviation or shaking of the LED display module 2 due to loose fixation during the gluing process, ensures that the opening of the silk screen stencil 4 accurately corresponds to the position of the LED lamp bead 21, and avoids collision and interference between the clamp and the scraper 32 and the silk screen stencil 4, thereby improving the gluing accuracy and operation safety.

[0073] The present invention further proposes that the fixing mechanism 11 is positioning pins arranged in a row, which are used to be inserted into the positioning holes of the LED display module 2 to position the LED display module 2 , and the height of the positioning pins is lower than the upper plane of the LED display module 2 .

[0074] Among them, the positioning pin refers to a columnar structure that forms a geometric match with the positioning hole. Specifically, it can be made of metal or hard plastic material, and the plane positioning constraint is realized by multi-point plug-in method. Arrangement in a row means that multiple positioning pins are arranged in a linear manner. Specifically, an equal spacing or non-equal spacing layout can be adopted, and multi-point contact is used to enhance the positioning stability. The positioning hole refers to a through hole structure set at the edge of the LED display module or a specific position. Specifically, it can be formed by a stamping or drilling process, and its aperture forms a clearance fit or transition fit with the diameter of the positioning pin. The upper plane with a height lower than the LED display module 2 refers to the vertical spacing between the top of the positioning pin and the surface of the LED display module 2. Specifically, it can be ensured that the positioning pin does not protrude from the surface of the LED display module 2 by adjusting the installation height of the positioning pin or matching the thickness of the LED display module 2.

[0075] Specifically, when the LED display module 2 is placed on the operation table 1, the positioning holes at its bottom form a corresponding relationship with the positioning pins arranged in rows on the operation table. By pressing down the LED display module 2 to insert the positioning pins completely into the positioning holes, the contact surface between the positioning pins and the hole walls is used to restrict the displacement of the LED display module 2 in the horizontal direction. Since the positioning pins are distributed in rows and inserted into multiple positioning holes, the degrees of freedom of the LED display module 2 in the X-axis and Y-axis directions are synchronously constrained. The design that the top height of the positioning pins is lower than the upper plane of the module enables the screen printing stencil 4 to directly cover the surface of the module during the glue scraping process, avoiding interference between the positioning pins and the screen printing stencil 4. At the same time, the structural feature that the positioning pins are embedded inside the module can also eliminate the problem of occupying the edge space of the module when using a fixture to clamp from the side.

[0076] Adopting the fixing method of inserting positioning pins into positioning holes, the degrees of freedom of the LED display module 2 are directly restricted through mechanical cooperation. The positioning accuracy is determined by the hole-pin fitting tolerance, avoiding the influence of clamping force control on the positioning stability. In addition, the positioning pins are completely embedded below the module, and no protruding structure will be formed on the surface of the module, providing an unobstructed operation space for the full-coverage glue scraping of the squeegee on the module surface.

[0077] Through the above technical solutions, the present invention realizes the precise positioning of the LED display module during the glue coating process, preventing the problem of uneven glue coating caused by the occlusion or interference of the fixing device. The cooperation mode of the positioning pins and the positioning holes ensures that the LED display module 2 does not displace during the glue scraping process, enabling the adhesive to completely cover the surface of the LED lamp beads 21. The structural design that the height of the positioning pins is lower than the upper plane of the module further avoids the physical interference between the stencil and the fixing mechanism, ensuring the continuity and consistency of the glue coating process.

[0078] The above description is only for the embodiments of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for gluing the surface of LED lamp beads, characterized in that: include: S1. Prepare a preset number of openings on the silk screen plate, wherein the size of the openings is the same as the size of the LED lamp beads; S2, placing an LED display module with a preset number of LED lamp beads on an operating table, and positioning it by a fixing fixture so that the LED lamp beads on the LED display module correspond to the openings on the silk screen; S3, leaving a predetermined distance between the screen printing stencil and the LED lamp beads; S4. Pour the glue into one end of the screen printing stencil, apply a predetermined pressure to the scraper, and make the scraper scrape on the screen printing stencil, so that the glue on the screen printing stencil is scraped into the opening, and the glue is further coated on the surface of the LED lamp bead.

2. The method for coating the surface of LED lamp beads according to claim 1, characterized in that: After S4, it also includes S5, covering the surface of the LED lamp bead with release paper.

3. The method for coating the surface of LED lamp beads according to claim 1 or 2, characterized in that: The predetermined distance is selected between 0.2 mm and 8 mm.

4. The method for coating the surface of LED lamp beads according to claim 1 or 2, characterized in that: The predetermined pressure is selected between 0.2-0.5 MPa; the scraper angle is selected between 60°-75°; and the scraper speed is selected between 10-30 cm / s.

5. The method for coating the surface of LED lamp beads according to claim 1 or 2, characterized in that: The mesh number of the silk screen printing screen is selected between 200-450 meshes.

6. The method for coating the surface of LED lamp beads according to claim 4, characterized in that: The screen on the screen printing plate is woven from stainless steel wire or polyester wire.

7. A device for gluing the surface of LED lamp beads, characterized in that: The invention comprises an operating table (1), wherein a fixing mechanism (11) for fixing an LED display module (2) is provided on the upper surface of the operating table (1), a gantry (3) is provided on both sides of the upper surface of the operating table (1), a silk screen plate (4) is provided at the lower part of the gantry (3), the silk screen plate (4) is suspended above the LED display module (2), a screw nut structure is provided at the top of the gantry (3), a cylinder (31) is provided on the nut of the screw nut structure, and a scraper (32) is provided on the output rod of the cylinder (31).

8. The LED lamp bead surface glue coating device according to claim 7, characterized in that: The silk screen screen plate (4) is connected to the gantry (3) via a lifting mechanism (41) and is used to adjust the distance between the silk screen screen plate (4) and the LED display module (2).

9. The LED lamp bead surface glue coating device according to claim 7 or 8, characterized in that: The fixing mechanism (11) is a fixing clamp used to clamp the LED display module (2) from both sides of the LED display module (2); the height of the fixing clamp is lower than the thickness of the LED display module (2).

10. The LED lamp bead surface glue coating device according to claim 7 or 8, characterized in that: The fixing mechanism (11) is positioning pins arranged in a row and used to be inserted into positioning holes of the LED display module (2) to position the LED display module (2); the height of the positioning pins is lower than the upper plane of the LED display module (2).

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